The first recommendation would be to go to a Chamber of Commerce or a Board of Trade locally and to make a request to help with the contacts of potential importers.

Quick googling directed me to website of the Chamber of Commerce in Ethiopia: http://www.ethiopianchamber.com/

The Government of Ethiopia also hosted World Coffee Conference, so you may find additional information on event, and may be some useful contacts to start with.

The second option would be to get in touch with biggest Coffee Associations or to participate in coffee conferences/shows:

The International Coffee Organization (ICO)
Specialty Coffee Association of America (SCAA)
Specialty Coffee Association of Europe (SCAE)
Different coffee shows, conferences and festivals (here's the calendar and links with additional information can be found)


After how many days we should pluck coffee beans from its tree?

According to two sources I have read [1, 2], it takes around 5 years for a coffee tree to reach maturity and it will then yield approximately one pound of beans per year. In further depth, fresh coffee beans should germinate within 2-3 months while old ones can take up to 6.


Why does instant coffee have a poor reputation?

Because the taste and aroma are horrible. I've been places (for instance Shanghai and Beijing) where it's hard to get a cup of coffee outside of business areas catering to foreigners.

The instant coffee is terrible. It is not a pleasure to drink. It's only palatable (to me) with a ton of evaporated milk and a lot of sugar. For someone  who usually drinks coffee black this ruins the coffee experience.

To answer your question: for people who love the smell and taste of good, freshly roasted, freshly ground coffee - instant coffee simply doesn't compare. Hence the poor reputation.


I wouldn't go so far as to say that it's not a very high-quality grinder, it does extremely well for the price. The clumping is an artifact of:

Humidity
Heat from grinding
Type and roast of the bean

Grinders that produce almost no heat while grinding, to the point that they do it reliably enough for it to be a listed feature cost ten times the amount that you paid for your grinder. Heat during grind isn't an indication of a low-quality grinder, rather, little to no heat is simply an indicator of a very high-quality grinder. There isn't much you can do about this other than purchase a manual burr grinder and grind by hand very gingerly, which takes lots of time.

Tamping alone should be sufficient to deal with any clumps (at approximately 15kg of force) - if it's not, then you want to take a very close look at the beans you're using, and the level of humidity they're exposed to in storage. Is your grinder normally close to anything that produces steam? Is your kitchen air really humid? Are the beans stored in air-tight containers? If you have clumps that tamping won't take care of, you probably have a moisture problem.

It can also be the bean, some roasts just do not do well for espresso, no matter how fine the grind or how dry the storage.

Both Lavazza and Illy produce a very pleasant medium arabica bean that should work very well in your grinder. They are very consistent in production, delicious, and should give you a good baseline to select other beans that would work similarly well. You can get beans that weren't specifically produced with espresso in mind to work, but it takes a bit of tinkering. I recommend the above beans very often to people just getting started because they're delicious and very easy to work with.

Anyway, try one of those, see what comes out of the grinder. If you're still getting clumps that don't immediately break down when you tamp (tap the portafilter on the sides a few times before you tamp to help this) you could try cleaning the grinder, changing how you store the beans, or looking at a de-humidifier in the area that you keep them.


What factors contribute to differences between coffee beans?

As has been mentioned, the species of coffee makes a difference. There are something like a hundred different species, with Robusta and Arabica being the most common commercially grown by far.  Liberica is another species that is grown in small quantities and has a very distinctive taste.

Within a single species such as Arabica, there can be a huge number of varietals. Some are naturally occuring (such as Bourbon and Typica). Maragogype ("elephant bean") is also a naturally occuring mutation from Brazil. Others have been bred by research institutes. For example SL-28 and SL-34 are common Kenyan varietals.

Another famous varietal is the "Gesha" (sometimes romantically but incorrectly called "Geisha"). This came to light when an estate in Pananma "La Esmarelda" noted something interesting when they were cupping their coffee. By separating their harvest, they finally identified a small section which was contributing to the overall cup. This coffee went on to dominate the Cup of Excellence competition and set a world record price at the time. It's since been planted on other farms which brings up the next point.....

As has been mentioned, things like altitude, soil and micro-climate affect the taste. So the Gesha (or any other) varietal from one farm won't taste exactly the same as Gesha from another farm.

The way of preparing the green beans - washed, dry-processed, or a number of other methods, all have their effect on the final flavour. So even the identical cultivar harvested from the same farm but prepared differently will produce different flavours. (The difference between dry and wet-processed is very signficant.) The actual care taken during preparation is also hugely important - I suspect that if one is starting out with a decent high grown bean, this is what really separates speciality coffee from the mass produced stuff. It takes a lot more care to prep the coffee carefully.

And I haven't even mentioned roasting and brewing....

I think this is what makes coffee so interesting - there is so much variety to try and enjoy.


You can try switching to cold brew coffee which is reportedly 67% less acidic than regular brewed coffee.

Regarding the caffeine amount, Wikipedia notes:

  Although less caffeine is extracted with the cold brew method, a higher coffee-to-water ratio is often used, between 2 and 2 1/2 times. This may compensate for this difference in solubility, resulting in a brew with equal, if not more, caffeine (although this is unlikely)

Additionally, despite the name, cold brew coffee can be enjoyed hot as well. Cold brew is essentially a coffee concentrate if steeped long enough. You can cut your cold brew with boiling water and serve it hot (Source), so you don't need to necessarily change the way you enjoy your coffee (if you enjoy it hot).

Hope this is helpful!


Blade grinders: any advantage over burr grinders besides cost?

The most important distinction between blade and burr grinders is the result:

Blade

Coffee beans circulate across the spinning blades. No matter how long or short the grind, there is extreme heterogeneity in particle size--that is, you will find larger bean fragments with near-dust-size ones, with everything in between.  If you use a pour-over or drip brewing method, you might even see whole beans floating to the top. Not surprisingly, you'll get very uneven extraction from these different particles, no matter what the brewing method.

If you grind long enough to decimate all the beans, you'll find a lot of fine coffee dust and sediment in your cup. Too short a grind, and you get a lot of beans and bean pieces that can't present enough extractable surface area to the hot water, leading to a thin, weak cup. Waste of coffee, to be sure.

Also, it's almost impossible to grind any two batches consistently, since grind time is dependent on bean quantity, type of roast, variety of bean--well, everything.  So today you'll get a disappointing cup, and tomorrow you'll get another disappointing cup for some other reason. Therefore I recommend a Conical Burr grinder.

Conical Burr

Beans move through once.  When you set your burr grinder to a certain fineness, there will be very little heterogeneity in particle size.  (N.B.  Spend more on the grinder, get a more even grind.)  This allows you to experiment with the grind as well as the quantity until it's perfect for you, then replicate that recipe perfectly every time.

Some tips on finding the right burr grinder for your needs:

Prices vary from $50 to $1500 for non-commercial grinders.  I'm happy with my $350 Rancilio, which I've had for 10 years without a hint of trouble.
How you like your coffee matters.  A more expensive grinder will do better fine grinds, as for Arabic-style (i.e. Turkish, Greek, Lebanese) coffee.  If you don't drink that, don't spend more for it.  Most burr grinders perform best in the automatic drip range.
The under-$100 burr grinders still manage to throw a lot of fine coffee dust into the grind.  Do your research before buying.
Consistency in grind is critical to good espresso.  If this is important to you, be prepared to spend as much on the grinder as you spent on your espresso machine.  It's for a good cause.  Why hobble your good machine with sub-par ingredients?


No. Unroasted coffee beans are denser and wetter than roasted beans and will not grind well. You will break your grinder trying, and even if the grinder succeeded, you'd get more of a mush than solid grinds.

Also, roasting ground green coffee would allow much more of the oils and gasses trapped in the coffee to leak out during roasting than even the driest roast. The resulting coffee would taste strange.


The CO2 stuck within coffee grounds produce the crema. At least, it is the main substance that forms the crema along with other minor components.

This is a very classic problem -and thus a question.

If you consider roasting, darker roasts have more crema as they contain more CO2 as the product of Maillard reaction. Here is a proposed previous post to be read. You may also want to check this previous post as it may lead to more reading on other metrics you may consider.
Grind has some effect, but limited. You may see the factors that effect crema production in espresso in this proposed previous post to be read.
As you have mentioned, time has a crucial importance. I think this should be your main consideration and you should focus on fixing this first. Basically, fresh coffee has more crema, always. You can read a lot more in this previous post.


How long should I leave my coffee for in a cafetiere (French press)?

Start with a coarse ground of coffee with about 1 ounce (28 grams) of coffee for about every 15 ounces (450 ml) of water. The water temperature should be below boiling, about 200-205° F (93-96° C).

Stir in about 1/3 of your water to let the coffee grounds "bloom" for about 30 seconds; then add the remaining water, cover it, and let it steep. The total brew time should be about four minutes. Then press the plunger to the bottom and pour.

Once the plunger is pressed, be sure to dispense the coffee into another container once that brewing cycle is done. If you let the brewed coffee sit with the spent grounds, it will start to develop a more-bitter taste and be somewhat over-extracted (unless that is an effect you are looking for).

Note: There is also a "cold-brewing" method which requires several hour of extraction, but that is likely to be outside the scope of what you are asking.


How can I achieve a very bitter flavor using the French press?

Bitterness comes from over-extracting the coffee. The factors affecting extraction are: water temperature, time, size of the grind, and to a lesser extent, agitation.

Using hotter water (above the usual 198F-202F), longer steep time, or a finer grind--or any combination of the three--will result in over-extraction, which will make the coffee more bitter. A darker roast will over-extract more easily as well, since an ideal extraction is typically 30-45 seconds shorter than a light roast.


How to get an even drip without Mr. Coffee filtration disks

If you do not care about filtering the water, you may cut round pieces from any paper filter and place them on top of the coffee pile in the basket before each brew. This should help to distribute hot water on the coffee pile.

Keep in mind, that this may be more expensive than using the regular filter as the cut pieces of water filter could be used once.


How to clean Delonghi Caffe Corso's pre-ground coffee funnel?

Such automatic machines have a mechanism inside that tamps the pre-ground coffee (put through the funnel) and then pulls an espresso automatically.

I cannot say if it really harms the mechanism, but I'd rather don't continue using the machine before removing the beans from the pre-ground coffee funnel. Very probably, the mechanism cannot adequately temp whole beans and may got scratched, crack, etc. I wouldn't take the risk.

I don't have that exact machine, but after looking at it's photo, by intuition I could say that it should have a door to access the mechanism on the left side. Remove that door and also remove the mechanism*. Simply remove any beans if you could see some and preferably rinse any coffee residue off the mechanism.

Then, you should have access from the funnel to the brewing mechanism to move the pre-ground coffee to the tamping area. There should be an upward hole somewhere. Very probably close to the mechanism, so you can see after you remove the mechanism. If it is not there, also remove the drip tray and check if you could find that hole from inside the machine. When found, you should be able to remove the beans from that hole.

I hope all goes well and you could continue using the machine.

(*) The mechanism should be modular for cleaning. Most of the time you could remove the whole mechanism by pushing a lever or something similar, then rinse it under tap water.


Does Wacaco really produce hot espresso (and how)?

Well according to the video presented on the website you have to provide hot water.

To my understanding of the machine's principle as well as physics there is absolutely no way it could produce hot coffee from cold water. The confusing quote from the FAQ

  Minipresso produces at ambient condition (75°F, 24°C), an espresso at perfect temperature (152°F, 67°C in cup) with a nice compact and persistent crema on top.

actually is about temperature loss during the process.


What is the difference between Melange and Cappuccino?

Melange describes different beverages with coffee in different places. The Melange from Vienna is indeed very similar to Cappuccino. However, Melange is sometimes not produced using Espresso, but normal filter coffee.

In Switzerland, in contrast, Melange is made with whipped cream instead of milk.


Posting comment on original question as an answer to benefit the Google creepy crawly bot.
Mochas are latte-based drinks. They use steamed and frothed milk, not just plain milk. Steamed and frothed milk are both produced by mixing air and heat with milk (typically by injecting steam, by heating and agitating, or by a combination of these) to make it creamier. You can make frothed milk without special tools by agitating milk aggressively while heating it on the stove. Use a hand mixer or immersion blender. If you like the effect, you can buy dedicated frother devices for about $30-40 online.


How long should I stir French press before "pressing"?

Based on my experience, I can say that stirring does not affect the brewing process in a French press a lot. The initial stirring is just for homogenously distributing the grounds in the water. Then, the rest of brewing happens itself in the water by chemical extraction itself and the main factors are time and temperature.

According to your question, I can say that you may be over extracting if you are waiting for the water to cool down.

One quick recipe and other related discussion are mentioned here.


How can I keep several pots of coffee warm?

Actually, this answer will eventually boil down to the forecasting of time dependent expected coffee consumption function of your guests.

You may expect that, right after a meal or right after they are seated people tend to drink coffee all together at once. Therefore, it is better to keep most (all?) of the pots filled up when you encounter them at first.

Then, the servers may check the pots and replace the most crowded tables' pots with empty tables' pots for a while. During that time, you may prepare your second tank of coffee brew.

To keep the coffee fresh, you may preheat the water, I assume. I'm not sure if your percolators are compatible but you may just heat up the water in the big one. Then use the smaller ones to brew smaller batches of coffee to keep rather fresher and smaller batches of coffee. Also, if some of the coffee remains, it is clear that a smaller batch will cost you less.

Besides, for serving decaf, my approach would be something like that: I would keep a few of the servers busy with serving decaf around the less crowded tables and only leave decaf pots in the most crowded tables. (Assuming that decaf will be consumed less.)

All and all, all of the above is my humble opinion.


Am I psychologically addicted to coffee?

Studies show that caffeine withdrawal is more of a psychological than a biochemical phenomenon. For example, if we know that stopping the consumption of caffeine leads to headaches, they will happen, because waiting provokes a reaction. This, in particular, is evidenced by a review of the 2004 journal Psychopharmacology, in the preparation of which scientists analyzed more than 50 articles from medical literature on a given topic.


Does ground coffee lose caffeine like it loses aroma?

Caffeine has a very very low vapor pressure 9.0X10-7 mm Hg at 25 deg C.  Source

Almost none would evaporate.


Get the best from a Gaggia Unica coffee machine

I suggest your first port of call should be the operators manual. Here is an excerpt:
• Empty and clean the coffee grounds drawer daily, with the machine turned on.
• After having removed the coffee grounds drawer, remove the liquids from the tray placed under the brew group.
Note: We recommend emptying the container if the machine is not going to be used for some days.
After brewing milk beverages, dispense hot water from the steam wand (Pannarello, if supplied) to obtain a thorough cleaning.

Every day, after heating the milk, remove the external part of the Pannarello (if supplied) and wash it with fresh drinking water.

Clean the steam wand weekly. To do this, the following operations have to
be performed:

Remove the external part of the Pannarello (for standard cleaning);

Remove the upper part of the Pannarello from the steam wand;

Wash the upper part of the Pannarello with fresh drinking water;

Wash the steam wand with a wet cloth and remove any milk residues;

Replace the upper part in the steam wand (make sure it is completely inserted).
Reassemble the external part of the Pannarello.

It is recommended to clean the water tank daily. For an easier removal of the
water tank, move the steam wand / Pannarello upwards:

Remove the small white filter in the water tank and wash it under running drinking water.

Reposition the small white filter in its housing by gently pressing and turning it at the same time.

Fill the tank with fresh drinking water.

Empty and clean the drip tray daily. Perform this operation also when the float is raised.


Our blood ph level drives our respiratory rate, if we are not breathing out enough CO2 we build up carbonic acid which in turn drives our respiratory rate higher until such time we have reduced our PH levels to a 'normal' range which is around 7.35 to 7.45 Ph.
 Simply put it's not possible to alter blood acidity or alkalinity without making yourself sick and usually ending up in an ICU.
The human body (and other species) uses a process called homeostasis which is our autopilot of systems integration to keep us alive and relatively healthy. Illness and chronic disease can impact on our bodies ability to balance itself but it will do it's best to keep its chemistry balanced.
There are a number of cases (Illness) where php drops (acidity) and the body moves other chemicals around to balance this which can have a knock on effect throwing other systems out (I.e. cardiac arrhythmias due to sodium/ potassium  / calcium imbalances etc.). There are other cases where calcium.is scavenged from our skeletal system (which can cause early onset osteoporosis, and a cohort of other nasties.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5118493/

I studied medicine and am a registered Paramedic and a massive consumer of fresh ground black coffee.
Hope this helps....


Coffee is going to be extinct by 2050, some claims by 2080

A web search for "coffee going extinct" finds many articles, e.g. in Business Insider, Aug. 30, 2016, A coffee shortage is looming — here's how soon it could be extinct.

the global coffee supply is currently at risk, with shortages already starting to affect the world.
half of the world's area that's deemed suitable for growing coffee will be lost by 2050 if climate change remains unchecked, according to a new report from The Climate Institute of Australia.
By 2080, the report estimates that wild coffee (which helps us find genetic varietals that might be more resistant to climate stress) could go extinct.
Temperature and heavy rain have helped a fungus called Coffee Leaf Rust spread through Central America and into South America, destroying crops. Pests like the Coffee Berry Borer are spreading for the same reasons.
Even a half a degree of temperature change can make a region that used to be a coffee gold mine unsuitable. Moving production to higher altitudes is not always feasible and can be especially difficult for the small farmers that make up 80-90% of coffee growers.
By 2050, half of currently suitable land will no longer be suitable, unless the world can limit warming to the 1.5-2 degree Celsius rise that was set as a goal at the 2016 Paris Climate Agreement, and really, even 1.5 degrees is pushing it for most farmers.

From the report:

Over 120 million people in more than 70 countries rely
on the coffee value chain for their livelihoods.
Many countries where coffee exports form a main
plank of the economy are also amongst the most
vulnerable to climate risk.
Crop adaptation strategies include developing more
resilient production systems, diversifying crops,
and shifting plantations upslope. The global trend,
however, is towards intensification as producers
seek to lift yields at the expense of more complex
and carbon-rich landscapes. Ultimately, climate
change is likely to push many producers out of coffee
altogether.

Time Magazine, Nov. 16, 2012, Coffee Under Threat: How Wild Arabica Could Go Extinct.

Coffee grown on commercial plantations, like many other crops grown to produce high yields, lack genetic diversity — and are thus highly susceptible to disease. Wild Arabica, which makes up just 5% of Ethiopia’s coffee crop compared to other kinds of coffee, is thought to account for over 98% of the coffee bean’s gene pool and has an estimated value to the coffee industry of almost $1.5 billion per year.
If disease or climate change causes a die-off of commercially grown Arabica, it’d still be possible to re-engineer it from a wider genetic pool — which is why wild Arabica is so precious.

Also see BBC Magazine, May 24, 2015, Saving coffee from extinction.
The world might need to deploy climate engineering (CO2 removal or solar radiation management) in addition to reducing greenhouse gas emissions in order to limit the impact on food, water, and economic security.


What are these spots on the inside of my moka pot? Do I need to remove them?

Short story: They are probably aluminum oxide, but almost certainly some kind of metal oxide. You don't need to take any action unless they're affecting the taste of your coffee, and it shouldn't be. You probably can't (or shouldn't) really permanently remove them even if you wanted to.

Longer story...

This is a classic Bialetti model, and a classic Bialetti symptom. The vessel is probably made out of alumin[i]um alloy (though there are similar models that are made of stainless steel, your picture seems to be looking down into the bottom heating vessel, and it looks like the classic aluminum species). Unfortunately the symptoms you're seeing, from my perspective, is a classic failure of the Bialetti design. Aluminum tarnishes (oxidizes) somewhat readily, especially when it is hot and in contact with water. Correspondingly, the only way to use this thing is, indeed, to heat it with water.

The vessel, especially, needs to be rinsed and dried thoroughly in The Right Way. The "care" page for Bialetti (follow that link, then click on the "Care Use" tab; I can't figure a direct link) suggests to dry thoroughly and most tellingly "Do not reassemble the product until all parts are completely dry to avoid oxidation." Even if you're meticulously drying the thing, it's still going to be a little hot and a little damp; this is going to invite oxidation.

Standard ways of removing tarnish are even more damaging in the long term than just leaving them alone. Aluminum oxide generally protects the metal from further oxidation (unlike rust -- iron oxide -- which flakes off and facilitates further oxidation).

I have a stainless steel moka pot, and it's terribly tarnished on the outside from heating on a gas burner hundreds of times, but the inside is clean (and cleanable) as the metaphorical "whistle".

For completeness: It's also possible that they are mineral deposits; this answer to the other question that you linked has some additional info about that possibility. It would come from a buildup ("scale") from using "hard" water, and more so when nearly boiling dry (also not a good idea); filtered or distilled water is much less likely to do this. However, I think it's unlikely that you'd see scale buildup over the span of a couple dozen uses.


What is a good packaging when importing green beans to a temperate climate?

Anything that is air tight would be best. Grain pro, ziplock, etc..
Vacuum packing is optimal.


Is dark roast stronger than light roast?

Strength is an interesting wording, but some people use it. Mostly, caramelized or burnt flavors get visible during the roasting process.

Understanding Coffee Bean names as they relate to roast

As you may see in that answer, Wikipedia enlists roast degrees and their profiles. I would like to summarize them here.

22 °C (72 °F), Green Beans: You may prepare green coffee tea from these. But not the regular coffee.
165 °C (329 °F), Drying Phase: Beans dry out. You may hear the first crack.
196 °C (385 °F), Cinnamon Roast: A very light roast level which is immediately at first crack. Sweetness is underdeveloped, with prominent toasted grain, grassy flavors, and sharp acidity prominent.
205 °C (401 °F), New England Roast: Moderate light brown, but still mottled in appearance. A preferred roast for some specialty roasters, highlights origin characteristics as well as complex acidity.
210 °C (410 °F), American Roast: Medium light brown, developed during first crack. Acidity is slightly muted, but origin character is still preserved.
219 °C (426 °F), City Roast: Medium brown, common for most specialty coffee. Good for tasting origin character, although roast character is noticeable.
225 °C (437 °F), Full City Roast: Medium dark brown with occasional oil sheen, roast character is prominent. At the beginning of second crack.
230 °C (446 °F), Vienna Roast: Moderate dark brown with light surface oil, more bittersweet, caramel flavor, acidity muted. In the middle of second crack. Any origin characteristics have become eclipsed by roast at this level.
240 °C (464 °F), French Roast: Dark brown, shiny with oil, burnt undertones, acidity diminished. At the end of second crack. Roast character is dominant, none of the inherent aroma or flavors of the coffee remain.
245 °C (473 °F), Italian Roast: Nearly black and shiny, burnt tones become more distinct, acidity nearly eliminated, thin body.


There are a few elements to this answer, so I'll try to tackle them one by one.

  is it possible to brew another cup with the used grounds...?

Yes. It is physically possible to do this. Just do what you described and voila, more liquid into the next mug.

  this would be the same as using more water and brewing over a carafe to brew twice as much coffee

This is where you are wrong. Brewing coffee is chemistry, whether you are using a Chemex or an espresso machine or a cheap drip machine. Each stage of brewing produces different flavours from the coffee. I can't guarantee this is accurate but here is an example of what I'm talking about.

The first part of your pour controls the bitterness of the coffee. The bloom helps to get rid of CO2 and dissolves oils on the beans and in the grounds. It will develop your "body".

The second part of your pour will determine the sweetness. Some people swear by small pours over a longer period of time, while others prefer the ease of just slowly filling the brewer evenly.

Finally, the last half of your pour controls the intensity of your cup. This is where your question comes in. More water in this last section will produce a weaker cup, and less water a stronger one.

All of these parts of the pour need to be melded together to create a delicious cup of coffee.

Pouring your first cup then re-using the grounds for the second one means the second cup misses out of the main part of the brew. Yes, the liquid will tastes like coffee, but will not have very much caffeine, and will lack the flavours present in a well-brewed cup. You're basically making ultra-weak, bland coffee.

If you want to make more coffee and don't care about the strength, brew a larger batch into one carafe, then swirl and split it between tow cups. You should adjust your grounds-to-water ratio accordingly though.

I hope this helps you answer your question!


How many cups of coffee is it safe to consume per day?

I would recommend scanning the DSM-5 (Diagnostic and Statistical Manual, 5th edition) on caffeine and coffee addiction, as well as looking at independent studies.

Because caffeine is the most widely consumed psychoactive substance there have been many studies done on the benefits and side affects, both of which can be highly dependent on what type of person you are specifically.

Generally speaking, caffeine is considered safe for healthy adults, and you should guage your consumption based on what you think fits your lifestyle


What's going on inside a Nespresso capsule?

Well, as you have yourself conclude that they have no difference regarding the amount of coffee (6 g). I just gonna put there an important note that some people miss.

Espresso capsules are made to be extracted as espressos and lungos, as lungos. The point of this is that Nespresso's lungo coffees are supposedly designed to have a more balanced flavor over a longer extraction/more diluted in contrast to the espresso which was made and evaluated to be drink in a single, stronger shot.

As for myself, I had both ways already and I do believe that at least for the espresso capsules, stick with espresso size (especially if you are using a 3rd party capsule). Nespresso's lungos are often too watery, in my opinion.


Can I leave the basket in the portafilter after pulling the shots?

The space between them is very hot to be cleaned right after preparing the espresso, actually. It is better to wait for a while and then remove the portafilter to clean if you are not planning to prepare a second one right after. See image below from a manual.

The space in between can be cleaned after given number of use. E.g. after every 50 use.

Normally, I tend to use decalcifying agents after per 100-150 use. Then, I also remove the parts and clean thoroughly. Otherwise, I just wipe the space in between with a wet cloth.


Is there a way to economically store freshly roasted coffee under vacuum?

Yes, there is a way to store freshly roasted coffee - or even store bought roasted beans - at home under vacuum without expensive equipment.  I drink wine and have collected a couple of wine storage devices over the years that I no longer use.  One of these is a bottle stopper with a one-way valve in the top and a vacuum pump for removing the air from a partially consumed bottle of wine.

My idea was to clean out the bottle and fill it with freshly roasted coffee beans, then use the vacuum pump and stopper to apply suction to the bottle to encourage the carbon dioxide to exit the beans without worrying about oxygen making the beans go stale prematurely.

I've found that the beans emit enough carbon dioxide gas to require re-pumping the bottle for the first day or two, but after that it will hold a vacuum indefinitely.  I've added erasable labels to the bottle to record the type of roasted beans I have inside.  Two standard wine bottles will hold about 610 grams of roasted beans, or about 700 grams of unroasted beans, which is 7 batches in my SR 500 roaster.  These are Ethiopian, YMMV.


There are "basket-shaped" filters, which I think is what you're looking for. In my area, they're just as common as "Melitta-style" cone-shaped filters; you should be able to find them at most markets / grocery-stores. They come in various sizes; you're probably looking for one of the smaller ("junior size") variety.

From this previous answer, here's a picture of what you're looking for, I think: a basket-style filter:

You can also find them online -- one example of the "junior size" basket filter, which is what I think you want based on what you said about the size of the machine/filters. There are 3 main sizes (and probably more): "junior size" (for ~2-6 cup machines -- as linked above), the most common normal/medium size (for 8-12 cup machines), and the large/extra-large size (for large/commercial 20+ cup machines).

They tend to be inexpensive and come in large packs... I hope you drink a lot of coffee ;-)


A cup of coffee is definitely a solution, in the sense that it is composed of dissolved solutes. The solvation occurs once water is introduced. While, there is always a limit to how much of a substance can be solvated in a given amount of solvent, with coffee you're likely to not reach the point of creating a super-saturated solution in normal conditions. If you were to take a pot of brewed coffee, and boil it, removing the solvent (water) you will likely reach a point as to where the solution is supersaturated, followed by precipitation of a crude extract.

Now is coffee an emulsion? I have heard that typical brewed coffee contains oils from the bean (likely oils that can be seen on darker roasts). If this is the case, then we could say that coffee is both a solution and an emulsion!

EDIT: I know this is an older question but I want to clarify some definitions:
Under IUPAC definition of an emulsion:

  Note 4: An emulsion is termed an oil/water (o/w) emulsion if the
  dispersed phase is an organic material and the continuous phase is
  water or an aqueous solution and is termed water/oil (w/o) if the dispersed
  phase is water or an aqueous solution and the continuous phase is an
  organic liquid (an "oil").

So, when I say coffee is a solution, I'm referring to dissolved solids in the aqueous phase (an aqueous solution). When I say it's an emulsion, I'm referring to the "oils" of the coffee dispersed in the aqueous solution. By the above definition, coffee would qualify as an o/w emulsion composed with an aqueous solution.


Weight loss between harvest and pre roasting

Dry enough = 12% moisture content
Weight loss by roasting = 12-18% of green bean weight
Volume loss = opposite; coffee beans puff up after roasting


An Irish coffee is traditionally a strong sweetened (with muscovada or demerara sugar or syrup) coffee with a doubleshot of Whisky (I guess around 40-50ml for a glass of coffee of 150ml) and a layer of aerated cream on top of it.

The coffee

I don't know what was used traditionally, I assume some kind of turkish coffee (or "Cowboy coffee"), where the grounds steep in water just of the boil for a few minutes or percolater coffee. Today I would probably use french press coffee or AeroPress with a metal disk instead of paper filter. You should keep in mind, that the coffee-sugar-whisky mix has to be higher in density than the slightly whipped cream. A pour over is likely too delicate (in taste and density). You also don't want coffee that's too strong (like espresso) because it would cover up most of the Whisky taste. Irish whisky tends to be lighter than Scotch or Bourbon. Add brown sugar to taste, but keep in mind that it is used to increase the density of the coffee-whisky mix as well, so one tablespoon should be added (for a glass of coffee as defined before).

Whiskey

Well it's called Irish coffee, so I would use Irish whisky. However I'm sure it's worth experimenting with different whiskys, trying to fit them to the flavor profile of the coffee. If you have a very nutty, chocolaty Brazilian coffee, maybe a smoky, spicy Bourbon fits better. I don't know much about whisky though. I'd just try different things. If you are afraid of too much alcohol evaporating, you could just wait until the coffee is cooled down to below 79°C. You can't drink it before that anyways, it would be too hot. After brewing, add sugar to cool it down, then I would wait until it's somewhere around 75°C, add the whisky, which will cool it down even further. Guessing to just below 70°C. Add cream and drink.

Cream

As said before, the cream should float on top without mixing with the coffee. Thus it has to be added after, which is usually done over the back of a spoon. It should be whipped lightly, but not too much either. You want it to be of a creamy, slightly aerated consistency. You drink the coffee through the cream.

Here is a link to a recipe similar to what I wrote, although theirs has some twists like nutmeg in it.


How should I distribute coffee from a small roaster?

If you're shipping 14 oz or less, USPS First Class Mail is an option which will save you quite a bit of money over USPS Flat Rate, and will definitely be less than UPS or FedEx small packages. If you do your shipping through ShipStation or negotiate your USPS rates, you can optionally get your First Class Mail bumped up to anything under 1 lb. which could help you out further.

That being said, I would think that it'd be your goal as a business owner and roaster to ship more than 14oz at a time - i.e. get your customers to order multiple packs of 12 or 14oz. That would bump you up into the 2-3 lb range which can no longer be sent via First Class Mail, but it could go out via Priority or Priority Flat Rate. More costly, but usually 1-3 day delivery time on Priority Mail which is nice.


Will emptying used coffee grounds into the sink drain damage my pipes?

You don‘t need the advice of coffee drinkers, you need advice from a plumber (which I am admittedly not, but I have enough contacts in the industry) and a gardener to chime in.

In short: Don’t do it.

Coffee grounds may smell nice and there is that persistent old wives’ tale that will claim that it has [some random positive effect]. It’s not true. Any plumber will tell you that it’s best to pour nothing except liquids down the drains. Coffee grounds are particles that may

clump together
collect like sediment in traps
bind to other fatty residue
provide food to microorganisms that form that slimy and stinky biofilm in the pipes.

And yes, most plumbers will love you for the habit of washing down your grounds, because it keeps them in business.

Coffee grounds are lovely additions for compost, so either simply add them to your garden compost or treat them like you would any other plant-based kitchen waste.


4M is a term mainly used among Italians for espresso. It is a placeholder for four words that start with "M" in Italian that affects espresso preparation. Some information can be found here.

These M's are:

Miscela: The coffee-blend; it covers the selection and blending of the beans as well as proper roasting.
Macinazione: The grinder; proper grinding of the given blend and its usage when its still fresh.
Macchina: The espresso-machine; usage of the given grounds with a proper espresso-machine.
Mano: Skill of the barista; usage of all above with skill.


What is the difference between a Blend and Single Origin coffee?

Many of us continuously discuss origins on this site. I searched through the site, interestingly cannot find a short, precise definition.

Sometimes, variety is confused with single origin. So,  I would like to start with this.

Taxonomically, Coffea genus has several species and we consume three of them as the coffee drink. These three species have several varieties. They may be thought as varieties of dog from a biological perspective. Same species, several properties.

For coffee though, the variety is not the only criteria that affects the quality of a bean. Cultivation, climate, soil, irrigation, harvesting, drying and peeling the fruit from the bean,  drying the bean are all affect the bean quality. So, if you have a specific variety and also you can guarantee the region and the aforementioned process is stable for a batch of beans, you call them single origin beans.

Blends are "blends" of several single origin coffee beans to produce the flavor characteristics of more than one single origin coffee. For a recent related post on blends please check this:

What are the basics of creating an espresso blend?


Why does coffee taste better out of ceramic cups compared to a paper cup?

Both cup material and temperature are in play here, I think.

A big part of the coffee taste (and experience as a whole) is the aroma. I personally find that paper cups (not surprisingly) smell and taste like paper. Ceramic (or glass, porcelain, etc.) should be practically neutral. Any smell you get from the cup could affect the perception of taste of the contained beverage. If the cup has a plastic lid, that could contribute both to its own smell, or holding-in / reducing the coffee aroma that you smell, also. (Aside: there are some interesting links to the physiology of smell and taste interplay at the Wikipedia article on taste.)

The very experience of drinking from a paper cup versus a ceramic cup is different; heft, shape, handle, other aesthetics, etc., though this probably reduces to personal preference.  For example, I find sometimes that my lip sticks to the outside of the paper cup, which is unpleasant (to me, anyway :). A plastic lid could be a factor here as well.

Temperature may also be a factor. For example, temperature can affect the perception of bitterness. A properly pre-heated ceramic cup/demitasse will help the brewed coffee be at a consistent temperature (without shocking it after pull) and keep it warmer for longer (so it doesn't cool down too quickly). Such temperature changes could result in a difference in taste; keeping brewed coffee at a consistent temperature is recommended -- that and some other general properties are listed here. Temperature stability of the brew will probably be different between paper and ceramic.


Does drinking coffee immediately after lunch or dinner impact health?

I think this is a rather broad question to answer. Are you looking for overall health effects of coffee or specifically for effects on digestion after eating?

In the former case, recent research has delivered very strong evidence that drinking a moderate amount of coffee (about 3 cups a day) has strong positive health benefits, reducing premature mortality quite dramatically. Among others coffee likely has positive effects on cardiovascular diseases, can be preventative to some types of cancer and alzheimer diseases and has positive effects on diabetes. See for example here, here and here.

The latter case is less conclusive I think. There have been studies showing that coffee (the chlorogenic acid in it) reduces glucose intake from digestion. While a decrease in nutrient intake seems like a bad thing at first glance, it may be beneficial for patients of diabetes, because it regulates glucose intake after meals and may help in preventing spikes/drops in insulin levels. I guess for someone struggling to get enough nutrients (due to other digestive diseases for example) excessive coffee consumption could have adverse effects. For healthy people moderate amounts most likely don't have negative effects (see the linked studies). There's also some evidence that coffee has beneficial effects on your microbial composition in your intestines (see here)

There's some other less severe potential issues that might arise, like an increase in reflux symptoms, due to excessive production of stomach acid (however dark roasts of coffee might even have acid reducing effects).

So overall I'd argue that the potential health benefits by far outweigh negative effects, except maybe in some cases of pre-existing conditions such as diseases of stomach and/or intestines.

References:

Gunter M. et al. Coffee Drinking and Mortality in 10 European Countries: A Multinational Cohort Study. Ann Intern Med. 2017;167:236–247. doi: 10.7326/M16-2945
Jaquet M. et al. Impact of coffee consumption on the gut microbiota: A human volunteer study, In International Journal of Food Microbiology 2009; 130.2: 117-121, https://doi.org/10.1016/j.ijfoodmicro.2009.01.011.
Poole R. et al. Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes. BMJ 2017. doi: 10.1136/bmj.j5024
Song-Yi Park et al. Association of Coffee Consumption With Total and Cause-Specific Mortality Among Nonwhite Populations. Ann Intern Med. 2017;167:228–235. doi: 10.7326/M16-2472


Will cold water result in cooler coffee with drip coffeemaker?

I hardly believe this is directly related to coffee. Still, as a more than 15 year experienced engineer, I would like to answer this question.

The answer is simply and clearly "no".

For the water to be able to travel to the top of the drip coffeemaker machine, it requires to gain some latent heat by changing its state to gas phase first. That's It simply means, it needs to be vaporized first.

Then, just at the top of the coffee and filter, there is a condensation space. At that space the gas (vapor) returns back to liquid phase (water) and starts to drip. Therefore, you obtain a slow flow of heated (to the near evaporation point) dripping water.

I cannot think any other way of bypassing this flow. Even in cheaper drip filter coffee makers.


Instant coffee has less caffeine than percolated and filter drip?

With instant coffee, you are not "practically eating the beans;" you are drinking reconstituted dried coffee.

To create instant coffee granules, the manufacturer first brews the coffee using conventional methods and then either freeze-dries or spray-dries the coffee to create a soluble powder form. Dried coffee.

The amount of caffeine in the instant coffee will depend largely the original brewing process. Since commercial instant coffee is created in very large volumes, they are likely extracting coffee faster than our meticulous home-brewed methods. So while caffeine is water soluble, it takes more time for the caffeine to be extracted and absorbed in the water than other compounds. And "more time" is not something that the mass-produced instant process allows. Less extraction time = less caffeine.


What is the reason that Aeropress coffee is more digestible?

The digestive problems you've experienced may be due to the acidity of the coffee. Now lighter roasted coffee will definitely be more acidic so the roast level of the bean can be at play. Not only that, but underextraction can cause high levels of acidity also.

The only discernible difference I can garner from what you've told me is that in the Aeropress there is a slight form of full immersion brewing. This will better encourage all parts of the coffee to be well extracted and so reduce the acidity of the resulting cup.

If you're curious as to what the real cause is, buy two different batches of beans, one medium-dark roast and one light roast. Then perform Aeropress, French press, pourover, espresso and possibly drip extractions with both beans and note down your gastric reaction to each cup. If there is almost no significant difference between any of them to how it makes you feel i.e. it seems to occur at random, you might just be hyper-sensitive to small changes in acidity caused by the differences in the imperfections of each extraction.

Good luck.


Does anyone have experience with this brewing method?

The biggest drawback is that you might add the grounds to too hot water. Especially avoid adding the coffee to water that is still boiling. Wikipedia has some references about the temperature and it states that boiling water will extract bitterness instead of aromatic oils. So just make sure to wait a moment after taking the water off boil.

Second drawback is that since the grounds remain in the pot in contact with the water, you have to empty the pot entirely once the coffee is "done". Leaving the grounds in contact with the water for longer times will only add betterness to the coffee. Of course this is no problem if you only make one cup, but prepare to have a (pre-heated) container ready if making more cups.

Related to the second drawback is that the extraction will continue in your cup because of the sediment, but in my opinion most people will not even notice it affecting the cup.

Coffee oils make it to the news from time to time. Since this coffee is not paper filtered it contains more oils. Some like the taste, some do not. Some link coffee oils to cholesterol levels (I do not..), which might be a personal drawback to some.

Offtopic: the method you describe is actually how my granny makes coffee, with a little twist (that I dislike). After adding the grounds, she heats the water to boil again and quickly removes it from the stove after first signs of boiling.

Edit: Just wanted to mention that none of the drawbacks I listed is unique to this method.


Is it possible to roast coffee in an industrial glass kiln?

If you can run the kiln at sufficiently low temperatures and have a solution for stirring the beans, yes you could roast coffee beans.

"Drinkable" on the other hand is a hard to quantify term.

Ideally, you would roast the raw beans slowy until 200 - 230 C over a time window of 15 - 25 minutes, depending on desired darkness and roast type.
This allows for a long and slow Maillard reaction and reduces the content of chlorogenic acid.
Your extremely hot kiln ("cold" glass techniques use temperatures over 800C!) woud be even harsher than industrial roasters with their "90 seconds at 400 C" method. No time for a good Maillard reaction and reduction of chlorogenic acid.

So while you probably can roast (= darken) the beans in a kiln if you are really quick, the results would lack the aromatic profile desired in good quality roasts and the probability of having just a "burnt and sour" brew is extremely high.


What Factors Influence Crema Production In Espresso?

I hereby copy a very nice statement from the conclusion of Illy & Navarini's survey paper:

Most of the data reported in the present review may suggest that espresso brewing can be described as “a quick way to transfer carbon dioxide from roasted and ground coffee to a small cup by means of hot water under pressure”. This then leads to the facts that for espresso coffee, carbon dioxide has to be:

generated by roasting
maintained in the bean by proper packaging
maintained in the ground coffee
solubilized in water
released into the beverage.

In this framework statements such as “any error in grinding or in percolation, in temperature or extraction level, has an immediate effect on denounced by the color, the texture and the persistence of the foam” or “the foam is the signature of a well-prepared espresso” can be well justified. In fact, foam volume, persistence, and consistence are the consequences of the carbon dioxide content originally present in the coffee. In addition to the importance of carbon dioxide in espresso coffee foam, we believe that carbon dioxide can play a role even from a taste point of view.

Therefore; you need to find fresh nice Arabica beans, roast properly, degas for the correct amount of time, grind them well, brew appropriately with decent water right after grinding.

Note: Please see this discussion for the use of the percolation in scientific papers. It simply means brew.


How coffee activates the nerve cells of the brain and what is the mechanism of it?

Caffeine blocks the adenosine methabolism in the neurons which normally manages the tiredness and sleep.

Here is a very nice informative video if you prefer to watch.

Adenosine molecules are released by neurons during the day and after they reach some concentration, they activate the adenosine receptors of the neurons of our brains. This is a mechanism to stop us being extremely tired and makes us sleep regularly for daily maintenance of our body.

Caffeine is a very similar molecule to adenosine in the molecular scale. So, it tricks the receptors as if it is adenosine. But, it doesn't activate the sleeping procedure. So, as a result, we block our sleeping cycle by masquerading adenosine with caffeine for a while. After a while, caffeine is removed from our brain by blood flow and everything returns to normal.


In general, it's best to not store ground coffee. If quality really matters, then the real answer is to back up. Try to grind only enough coffee for what you're using immediately to brew with. If you're buying preground coffee, then storage and optimal quality become somewhat trivial.

Once the surface area of the coffee is increased (by grinding it), the majority of the coffee is exposed to air, accelerates the decomposition of the coffee, meaning it likely isn't going to stay fresh for long anyway. Think of it like opening a dry, red wine. Since it's been opened, it's going to turn faster than it being left in the bottle because it's been exposed to atmosphere.

So in short, if flavor and freshness really matter, try not to store ground coffee if at all possible.

EDIT

If you really must store ground coffee, keep it sealed airtight. The exposure to atmosphere is going to be the strongest catalyst in making your coffee less than fresh.


Can I substitute Gaggia Descaler for Sage 'the Descaler'?

I think the Gaggia Descaler would work fine in any espresso machine. Just use the same procedure and amount that worked for the Gaggia machine (or use the directions for The Oracle).

I have never bothered to buy any commercial descaler, since they seem overpriced to me. I buy pure citric acid powder over the internet, and use that for both a Gaggia Classic and a Ponte Vecchio Lusso.


Why do we need to fold the border of filters?

I did a little bit of research at the site of inventor of the coffee filter. It's Melitta from Germany. In the german FAQ I found the following:

Warum falte ich Filterpapier vor dem Einlegen um?
Damit die Kaffeezubereitung optimal funktioniert, muss das
Filterpapier genau in die Form des Filters gebracht werden. Dies
geschieht, indem Sie die beiden geprägten Ränder umfalten. Das
Filterpapier schmiegt sich dadurch an den Rand des Filters an und
sitzt tief im Filtereinsatz. Durch diese gute Passform kann sich das
Filterpapier während des Brühvorgangs nicht einklappen

In English:

Why I fold the coffee filter?
For a good result the coffee filter must be in exactly the form of the
drippter. This is done by folding over the two embossed edges. The
coffee filter is nestled by the edge of the dripper and sits deep in
it. Through these good fit, the coffee filter can not collapse during
the brewing process.

Additional fact: The coffee filter was not invented by Melitta the company, but by Melitta Bentz.

Sorry for that bad translation. My English is really not the best. Please improve me!


When the water has too short of a time to extract the flavor from the bean.

Try grinding the beans a bit smaller.


Does French press coffee taste like instant coffee?

Use better coffee or adjust your recipe.
With a french press you can pretty much get the characteristics of every coffee out if you brew it properly.
If your coffee was bitter, tasted off or tasted like instant coffee, it was not the french press's fault (unless it was very dirty).
You can either try adjusting your brew recipe if you're convinced your coffee is good or you can try to find some locally roasted coffee. Search for "specialty coffee" or roasteries near you.


According to the Aeropress manual:

  Remove the cap and set it aside.  Push the plunger to eject the "puck"
  of spent grounds into the trash.  Rinse and/or brush away any grounds
  left on the rubber seal.  The seal has already wiped your chamber
  clean, so no further cleanup is needed.

  Always eject the puck right after brewing, and store your Aeropress
  with the plunger pushed all the way through or completely removed.
  Storing the seal uncompressed will keep your seal airtight for years.

  (source [pdf])


Reduce your dose. Having your puck stick to the brew head means the grounds are in contact with the brew head. If you reduce your dose by 1-2g the surface should be low enough as to avoid direct contact with the brew head. Depending on your brew head you might even get channeling if the surface is too high - immediately below the holes where water comes out it might dig a channel into your puck. If you can see dots on your puck after taking it out, it's probably channeling.
A wet puck in general also suggest too much coffee or too fine of a grind, check out this life hack from James Hoffmann, where he suggests letting the espresso run for a little longer so you can knock it out of the portafilter more easily.


How best to reduce tannins in black coffee?

Tannic acid grows exponentially for a while during roasting, then starts to decrease.

So, I can advise either you can add some  (aged) green beans or dark roast beans to your coffee to find the best balance for yourself before grinding. This may decrease the overall acidity and tannin level of your cup.


You need a high-protein plant milk in order to obtain proper froth as the froth is kept in shape by what are essentially entangled protein molecules. According to google, rice milk only has ~10% of cow milk's protein, which explains why it doesn't work well. Soy milk has pretty much the same percentage of protein as cow milk, so that is worth a try. Coconut milk has ~70% of cow Milk's protein.

Regarding the heating: try a different setting of your frother. Heating should work the same no matter what milk you use.


Starting a cafe -- simple and gradual ways?

Ah, I was going to make the same point as Travelling Particle - work in a coffee shop - but then you mention that you are in Japan.

First, you will need to find a roaster where you can get fresh roast daily or as needed - hopefully with a business discount. Get a decent grinder and I would go this route for brewing a cup:

It's doesn't get much simpler then this and it looks nice. The Japanese are a people that have a Tea Ceremony and they may appreciate this.


what is a good semi-automatic espresso machine for home?

There are loads of best espresso machine buyers guides out there. 99% of them recommend the Breville Barista Express.

I'd prefer something with a little more manual intervention like the New Gaggia Classic to be honest.

Cheers


Will the quality of the coffee change if I store it in a plastic bottle?

A short answer is "not significantly", assuming you just store your drink for the day, and there is no sharp changes in storage conditions (strong heat, freeze, etc.)---except warming up the amount you want to drink.

Coffee drinks are unstable, though, and a simple, freshly passed drip coffee tastes different (quality changes) with time. So quality will actually change over a day, although the difference is hard to notice (except people with very acute taste sense).

You are also adding milk, which softens the overall taste, so I think noticing changes in the coffee flavour is even harder.

Every vending machine around me (every 100m or so) sells coffee drinks in PET bottles. These bottles are stored for several weeks, and they sell pretty well. They taste fine for that price point and quality, and they are very stable. Of course, they do not include only coffee. They include milk, sugar, and hard-to-spell things. The last category does contain taste stabilizer, etc., so that is unfair comparison. I am just thinking it is interesting to see that coffee in plastic bottles in actually pretty common, especially for relatively short times.


Milk quantity and consistency in cortado, cappuccino and latte

There's a chart for that!

Here's a link to it, but I've also included an image below.

There could be some argument over cappuccino vs. latte as to which is "creamier" as the cappuccino certainly has more mil foam, but the latte has much more milk by volume and by ratio. On the whole though I'd say the latte is a less strong drink with a creamier texture even if the cappuccino is thicker.


How do I know if my aeropress is too loose?

How easy it is to push the aeropress plunger depends mostly on how coarse or fine your coffee is ground. It sounds like your grind might be too coarse, a finer grind will make it "less loose". A medium-fine or filter coffee grind will usually work best in this situation.

As another answer explained, don't put milk into the aeropress, it won't filter properly. You can add milk to the cup afterwards if you like.

About 20 seconds to push the coffee through the aeropress with light to moderate pressure (just leaning on the plunger) would be a good time. Your description of the water passing easily at first and the plunger being "too loose" sound like your coffee grind is too coarse.

Here is an excellent video showing how to use an aeropress brewer by expert baristo, Tim Wendelboe.


What is the basic differences between espresso, cappuccino, and latte?

I'm going to assume that you've had an espresso. It's a small-cup of coffee extracted under very high pressure. It's delicious by itself and some like to add sugar.

So, what is a latte?
Take a shot of espresso and add steamed milk

What is a cappuccino?
Take a shot of espresso and add steam milk.

So, what's the difference between a latte and a cappuccino? Are they the same thing?

No. (Unless you're in a really bad diner in which case you shouldn't be ordering lattes there.)

There are several differences between a latte and a cappuccino.

One is the ratio of milk to espresso. A cappuccino is 1-1 milk to espresso and the latte is 2-1 milk to espresso.

Another difference is that the milk is treated differently. In a latte the milk is heated as opposed to being frothed. In a cappuccino the milk is frothed (converted into a microfoam) to about double it's original volume. (If you've ever heated or foamed milk you'll have noticed how the milk changes state as it's being heated.)

Finally the way the milk and espresso are combined is different. In a latte the heated milk and espresso are poured together into a serving cup. Whatever microfoam might have been created while heating the milk is then poured over the top. In a cappuccino the frothed microfoam is poured over the espresso.

It gets more involved than this but I'll let others answer those questions.


No. That coffee (or caffeine or anything else in coffee) would stunt growth is a debunked myth.

Here's an article from the New York Times that cites a small university study that showed no relation in bone density/gain in adolescents. Another article from Smithsonian cites the same article and a few other studies from the NIH and others that show very little impact of caffeine / coffee on related growth factors, the other factors which are largely explained by other factors (e.g., sugar or other stuff from other types of beverages).

That said, caffeine and other chemicals in coffee have certain other effects, and certain people are sensitive. Here's a related article about some other coffee myths.


Coffee options for those with a weak stomach?

Preparation method will have a big factor in extraction, acidity (such as in @Patrick's answer) among them.  The method used (temperature, time, technique, filtering method) will have a big impact on what comes out in the cup. Astringency and bitterness might also be factors that have physical effects for you; see this article for a discussion of the differences between the two, causes, and related factors.

Try cold brew. Cold brew coffee will have lower acidity, and might be a good option for you; here's an article that discusses different preparation methods, but in the cold-brew section it has an anecdote of someone with similar "stomach".  Here's another on cold-brew and acidity. See also the cold-brew tag.

Paper filtering seems to remove some acids, but it's not clear whether these are the type that might argue with your stomach. For example, The AeroPress FAQ claims that their paper filter creates lower acidity brew, but I can't immediately find a better, proper reference.

Try some antacid. If you're experiencing heartburn, try a calcium-based antacid before and/or after drinking the coffee, and see if that changes things. (Disclaim: This isn't medical advice, don't take it if you shouldn't, talk to a doctor about meds, etc.).

Science! If you're into thicker scientific reading, here's a paper on extraction methods and outcomes, if you're into that sort of thing. It discusses various aspects of acids and acidity. It looks pretty dense.


Is Starbucks a fast-food like coffee company?

As far as actual speed, that based mainly on the barista working shift, the load, and amount of available equipment.  Starbucks does not have any patented magic equipment that  lets them pull shots faster than any other coffee house (that I am aware of).

If you enjoy their beverages, then there probably isn't any reason you shouldn't continue to drink it.  I would guess you are in the minority of people buy what amounts to black coffee from Starbucks.  Starbucks is a fairly divisive brand among most consumers.  Most of the people I have talked to that like their beverages are buying mixed drinks from them and not straight espresso, drip coffee or americanos.

Starbucks does sell organic, fair trade and the like specialty coffees as whole bean or ground.  However, the vast majority of their beverages sold daily is likely made with whatever their "espresso" blend is.  My personal opinion is that it's horrible and over roasted.   However, it's also consistently the same tasting and consumed on a fairly mass scale daily, so if there were any inherent dangers to it, we'd likely all be aware by now.

As a brand, Starbucks is mainly aimed at consistency.  In general, that's what fast food chains strive for as well, so in that respect, they are very similar.  Proper branding ensures that you can buy a product at any of hundreds of locations (or thousands) and it will taste the same.  However, many consumers prize quality and uniqueness over consistency.  In most industries (distilling, wine, food, beer) the most expensive and "highest end products" are items that were perhaps only produced at a limited run, or were very good in a particular year.  That mindset tends to be the antithesis of the mass produced "good enough for everyone" standards that huge market brands set for themselves.

TL;DR Summary:  Yes, Starbucks shares many characteristics with fast food companies.  The most notable aspect being their branding strategies and tactics.


The key here is extraction from the espresso coffee. Only so much desirable flavor and body can be pulled from a puck of coffee. So, then you might say, why not make the puck bigger? Well then that would force the water through a thicker puck, causing the extraction to be slower and longer, giving bitter flavors. The amount of pressure needed to make a desirable "pot of espresso" with a larger "puck" (or probably more accurately, a "slab" in this case) would be a wild safety hazard, since the pressure would be too immense for any cost-effective equipment to handle.

So, is it a technical limitation? Yes and no. I think it has more to do with being a tried process that gives repeatable, scientific results.


As your question is very open I will try to answer two common roots of your problem.

1) Too much coffee. Per cup of espresso it should be 7g of ground beans.

2) No "tamping". You probably did not compress the powder in the porta filter (called tamping). This is what it looks like:

So maybe you compressed it when you tried to place it in the machine.


No it's not a problem. Producers know that people at home often single dose their coffee, so I assume they consider that when producing a grinder (in fact most coffee shops that do pour over grind single doses as well). Maybe in some manuals it's written that you shouldn't let it run empty on very fine settings, but that's more to avoid warranty claims than because it would actually hurt your grinder and I assume they are referring to letting it run for minutes on end, which you probably shouldn't do. And why would you? The burrs in any case shouldn't touch each other at all, even on fine settings (or only at the flat part of the burrs, but certainly not the blades). I have yet to seen a grinder that was getting damaged due to the few seconds of running empty after your dose went through.


Does a decaffeinated coffee have zero or little caffeine in it?

We have yet to invent a process that removes 100% of the caffeine. When drinking decaf, the important question to consider is how likely you are to feel the effects of the trace amounts of caffeine that are left. That brings us, as most things do, back to the beans.

Arabica has (on average) only half of the caffeine that Robusta contains. Now let's say you have a bag of Robusta where 80% of the beans have 1 - 2% of their original amounts, and 20% of the beans have 15% of their original amounts. Drop by drop, a shot of Robusta is much more likely to keep you awake or elicit other natural responses to caffeine than an identically-sized shot of Arabica.

But let's take that into context and not pick on Robusta so much - the single shot we mentioned might only contain 20mg of caffeine in total, meaning you wouldn't notice the effects any more than you would notice effects from the Arabica. The point is, you could, so if you want to avoid caffeine, go with the milder bean and faster extraction.

Just goes to show, when you're talking about the characteristics of any coffee, the bean is pretty paramount - it can change the answer to any question completely in many cases.


What bean-to-cup machines are available with dual hopper system to allow regular and decaf at the same machine?

Many single-hopper machines have a little flap, drawer or similar opening where you can add ground coffee for one serving.
If you add one type of beans in the machine’s hopper you can use the second slot for the other.
The fact that the second one takes ground coffee doesn’t mean that half of your coffee drinkers have to use pre-ground, a good grinder should cost way less than a second machine or a dual hopper one. Just decide which group gets to use which setup. While we instinctively might say that the group that drinks more gets the simplest “just push a button” solution, maybe one fraction actually likes the “ritual” of the separate grinder.

Update:
As per request, I checked for examples.
This is the machine at my office: A BOSCH VeroCafe, you can see the opened chute.

The JURA machines I checked (randomly on the website) all feature “powder recognition for additional ground coffee variety”.
For SAECO I checked the (comparatively cheap) Incanto model and yes, this also has the “powder option” feature.


As the machine is cleaned thoroughly, we can eliminate any kind of blockage. Then, a very probable reason for this is the thermostat. If it starts malfunctioning overnight (it is possible as they are electronic controllers with a thermocouple attached), then the machine may overheat your boiler. This ends up over-pressure. If possible, compare the temperature with normal temperature first.


Different grinding size for boil coffee and coffee maker?

Yes.  For a drip coffee maker, most people will want to use a medium grind that balances getting enough extraction and still allowing the water to flow through the coffee grounds.  For immersion (boiled) coffee, you generally want a course grind that will slow extraction somewhat (reduce the chance of over extraction) and make the grounds less likely to end up in the final product.


How can I make filtering my cold brew easier?

Use a tea infuser!

I got a tea infuser with a very fine mesh and put my grounds in that. It holds fewer grounds than I used with the "raw" plunge, but it's much more pleasant to use: I just pluck the floating infuser out of the pitcher and empty the grounds from it. I may get a second filter, or a larger one, but for now I'm content making coffee more often because it's less of a chore each time.

There's no visible particulate in the resulting drink, though if I run the brew through a filter (which is a heckuva lot faster, as there's no clogging of grounds at all!) it comes out with a small amount of lint-like residue. And the last cup in the pitcher is much stronger than it used to be, but I'm not exactly complaining about that.

You could also go for an intermediate approach, using a tea strainer before you run the brew through a regular filter: that'll get the big stuff out fast so your filtering doesn't slow down. (Also, put a teaspoon in the funnel under the filter, so the grounds don't stick to the sides of the funnel through the paper. It gives the liquid more room to flow.)


Troubleshooting Moka coffee grind size vs sediments

A Moka grind is a tad coarser than espresso grind and ideally finer than standard pour over. If it’s too fine, you’ll see the excessive sediments or - worst case - even clogging up.
The size of the largest particles in your first picture are French press or even cold-brew worthy: I can see the curved, smooth outside of the beans. If you also get sediments, it means you have a very inhomogeneous grind, I would suspect a blade grinder instead of a burr grinder was used.
See that section of your first photo, with the extremes circled:

Considering the difference in particle size, you will always get over extracted and under extracted coffee j the same cup, independent of brewing method.
Your last picture shows a rather watery, thin coffee over the sediments, I would expect coffee from a Moka to be more opaque and possibly darker.
As a fix, you could try sifting the coffee to separate the various sizes a bit, but frankly, I never was particularly successful with that. Apart from that, I’d first try the batch in a pour-over setup and if that doesn’t work (e.g. clogging up the filter), move up to French press.


Is it possible to make a frothy coffee without an espresso machine?

Actually, the silky wet milk foam may be a problem if you cannot easily reach a steam wand. However, froth is quite easy. All you need to do is fill the milk texture with small air bubbles.

A nice tool to do this could be your French press. After preparing your coffee in a French-press, swiftly clean it and fill it with some milk. Pump the filter in and out for a while. This will inject small air bubbles inside the milk, so the milk quickly turns into textured froth. Then, you can use it as a topping for the previously brewed French-press coffee.

This is not exactly same as any espresso-based foamy beverage just like cappuccino. But, the result may resemble it.


Roasting suggestion for Behmor 1600+ for Rwandan beans

Your times are right where they should be.
Can you control the airflow and/or temps while you are roasting in a Behmor? If so, try to increase the airflow near or after the first crack.


If you live in or near a major city any large Asian supermarket should carry it or a substitutes to try.  In San Diego, Ranch 99 is one such market.


How is green coffee different from usual black coffee?

The green coffee beans are, if not spared for home-roasting, are very lightly roast coffee beans. They are known to be very fruity and light when brewed. You may try to use the regular coffee brewing methods but the result may taste too weak. You may also try to brew them for longer periods just like any other "herbal tea". I assume, longer periods in a French-press would do it. You may try different periods to find your desired taste.

Please see this previous discussion on green coffee:

How to create green coffee?


Does it make sense to buy smaller-sized bags of whole bean coffee to keep it fresher?

Trading off taste difference against price depends on how much each of them matters to you.

Storing an open bag of beans in the cabinet for 8 weeks probably does matter to taste, while a 4% price difference is easily in the noise.

Taste Difference

It seems fair to assume you care about taste differences since you're asking. So for that side of the comparison, it’s sufficient to ask whether you can taste any difference, and that’s fun and easy to test. See this answer on how to do a triangle test.

Here's an experimental design for coffee bean storage duration: Weigh out the coffee into small plastic bags, put half the bags in the freezer and half the bags in the cabinet, then at different durations, defrost a frozen bag while still sealed (so the beans don't get water condensation from the air), and compare the coffee it makes against a bag from the cabinet. I did this with medium roast beans listed as “high body” and “bold acidity” so degradation would be readily noticeable.

After 2 days, we could not distinguish the frozen from cabinet-stored beans. (That rules out the hypothesis that freezing hurts beans, at least when defrosted in the bag.) After 4 weeks, we still could not distinguish them. After 12 weeks, all tasters could tell, and with high confidence.

Caveats: That was just one kind of bean, made just one way, with 5 tasters who are no cross-section of the world’s population. But each taste test got “statistically significant” results for a hypothesis picked in advance. Good enough for me.

I doubled the duration between each test, hence I didn't test 8 weeks. The taste impact of 8 weeks storage is still in play. Do try the test at 4 and 8 weeks with your favorite coffee. For discussion’s sake, let’s call it likely.

Side note: If you want to stretch out the freshness of a 2 month supply, it’s viable to freeze some of it in small bags.

Price Difference

Perception studies have a notion of “just noticeable difference” (JND). A smaller difference than that is unlikely to be noticeable (not the same as “measurable”). A starting assumption for a new domain is JND = 1dB (as it is for audio volume) which is about 26%, but a quick web search gets us a JND threshold for price from Marketing As I know it:

  Why is it a 10% off sale fails to get your attention while a 50% off sale brings in consumers from the surrounding counties?
  The reason the 10% sale does not excite is that it is below the JND. Research has proven that the JND for price tends to be between 20 to 25%.

In context, a % comparison (whatever the percentage amount) assumes you have a budget or reference in mind for that expense. If the % difference blows your coffee budget, you could compensate by drinking less often, or better yet by making more of your coffee at home than from cafes. If you think of coffee as part of your overall food & drink budget, maybe you could make up a large price difference by drinking less soda or eating less meat (both of which are health and environmental improvements).


What is the Roasterie's city of fountains blend?

Beans that are sold by giant retailers aren't known for being great.  Most companies moving such a significant amount of coffee (and mostly cheaply) are mainly looking for a supplier who can provide a large volume and quality secondarily.  Dark roasting such beans effectively hides the origin flavors (or lack thereof) and provides a certain level of uniformity (you will consistently get the roast tastes).  It's unlikely the beans are "burnt leftovers" since that kind of sorting or sale to another company after over roast accidents would only add to the cost and complexity of getting the product to market.


What is the next best milk substitute for a latte?

Here's another take, but going in the direction more of performance for foam (i.e., more for cappuccino than latte), mostly because I found links about that :) and because steamed milk should foam. If you're not looking for much foam, the differences are probably less profound.

There's a few other plant-based milks out there also; coconut and rice weren't mentioned in the other answers. In sum, I know of 5 common plant milks: almond, coconut, hemp, rice, soy. But there are probably others as well.

Here's some comparisons, summarized from the linked articles:

YouTube video - milk froth-off. They compare rice, coconut, and almond. They got the best performance with almond milk, coconut did almost as well, and rice milk did not perform well.
MarkBittman dot com has an article on the search for a vegan cappuccino. It suggests that soy is the best alternative for foam, followed by almond. The text and comments suggest (but doesn't outright state) that hemp works well also.
The Peaceful Dumpling article (linked previously in @PythonMaster's answer; summarizing the original article's conclusions here) concludes that soy is best, followed closely by hemp, and that almond doesn't work as well.

The conclusions tend to be suggest that cow milk will perform better than plant-based "milks." This probably suggests that lactose-free milks (i.e., with lactase, like Lactaid and others) will be your best bet. Of course, you could always take a lactase pill and enjoy your cup with conventional milk. Various articles suggest that certain soy milks are best, and that coconut, hemp, and almond will also work.

There's a ton of other factors, but these probably reduce to preference: some milks will be sweetened, or import their own taste (e.g., almond, coconut). Others might have emulsifiers or other additives (such as carrageenan), which impact the steaming (maybe helping or hurting).

Another take would be to look at the "science" of what happens during steaming: it's a combination of fats and proteins that are being agitated and changed in the right way to make foam.  This CoffeeGeek article discusses frothing and what's at work; this was interesting for me, and might help you pick a milk based on protein and fat content among the various milk options.


Coffee addiction is not generally a problem as it is not even an addiction such that people afraid most of the time.

Caffeine molecules increase and stay at high levels if a person is a regular drinker. During this phase, your body reacts that and adapts to handle more caffeine.

It's like diving deep and staying there for some time. Then, if you rapidly swim up to the surface you caught caisson disease.

Human body is very resilient to changing caffeine levels. It can adapt easily. But, it cannot adapt so fast. If someone is afraid of being addicted, they can slowly decrease the amount of coffee they consume per day.

For example, think of someone drinks 6 cups a day. If decrease rate is a cup per three days, after 15 days daily consumption will be a cup per day. Seems reasonable with no headaches.


Why should milk used for coffee not to be served too hot?

Most cafés serve coffee beverages between 155°F - 165°F, but the ideal temperature for steaming milk on a home machine is between 150°F -155°F. Temperature really only starts to matter when it comes to the type of milk your steaming because different types have different burning points ex. Soy milk will burn before whole milk so maybe steam soy at a lower temperature. Generally, milk proteins will start to break down and burn around 170°F, but basically personal preference and what tastes right to you.


I find the very same problem with cold brew taking a long time. Though we have a few Q/A about this in the cold-brew already, I think could stand on its own!

I use a "two-phase" method: using first a "primary" or "coarse" filter, like a French press plunger as described here and elsewhere, or a metal mesh tea or coffee filter as described here, or even a sock or cloth as suggested by this question. This strains through quickly, but only filters the larger particles that would very quickly clog a paper filter. Second, I put it through a paper filter (I find Hario-style filters drain faster than Melitta-style filters). I find this works the best of any setup I have used.

For completeness, we have a few Q/A about this already. See for example making cold-brew easier for some more ideas about "pre-filtering"; see starting out and equipment for some other tips; and even try cold brewing with AeroPress.


Does breaching a stovetop milk steamer's double wall destroy it?

The double wall on this steamer is not there for insulation. That idea doesn't add up. An exterior wall will heat up before an interior wall if heated on a stovetop and would inhibit transfer of heat to the interior container...

I can think of two possible reasons for the double wall, but I must say, that double wall is an unnecessary added expense on the unit no matter the reason it was included...

1) In a double wall design, the exterior wall will cool down faster than a single wall would, since the exterior wall does not maintain contact with hot water. This means you can safely reuse the steamer sooner. This is kind of silly, though, since you can easily cool a single walled steamer by briefly running it under cold water.

2) A double walled steamer is more structurally durable than a single walled steamer. These units are sometimes built to withstand very significant internal pressure. The double wall could be part of such a design. This is kind of silly itself because steam pressure higher than a single walled unit could support is dangerous...

The exterior wall in any case likely does not play any part in containing steam. To be sure, I'd need to see the inside of the lid. It depends whether the seal is placed on the outside threads or the inner vessel and whether a gasket is used or not.


My Delonghi Magnifica ESAM 4200.s makes coffee and then cuts out. Any suggestions as to why?

If you have observed the problem on different outlets and even in different houses, the only common factor is the machine itself. The exact cause can’t be assessed via the Internet and unless you are experienced with repairing electrical machinery, I would strongly discourage you to start experimenting blindly. The missing error lights are not an indicator here, they would only signal a problem that an otherwise functional machine can detect via the built-in self-checks. Tripping a circuit breaker is in a different league of defect.
For your own safety: Please stop using the machine (faulty electric alone is bad enough, add water to the mix and it gets really dangerous), even if it seems to “work”, sort of. Contact a qualified service technician or the seller/manufacturer (especially if it’s still under warranty) and have them assess the situation.


There is a defined set of tasting note terms, the World Coffee Research Sensory Lexicon which is the basis for the Coffee Taster's Flavor Wheel.

Those terms are intended to name specific tastes and you can take a class to learn how to recognize them.

Since I've not yet taken such a class, I can't testify to the reliability or utility of "flavor notes" on packages, but surely some writers are way off in fantasy land.

Furthermore, some staffers at big coffee chains are not even clear on the distinction between flavor notes and added flavoring!


How long can we safely store cold brew concentrate?

In my experience, if you have sanitised your equipment properly you should get three to four weeks when storing cold brew in a ready-to-drink ratio in the fridge. My feeling is that concentrate would probably have a longer shelf life, but by how much I can't really say.

The taste will change over time depending on how well filtered the cold brew is. If it is only lightly strained or filtered, a lot of coffee solids will remain in the brew and make it stronger/bolder over time (sometimes it can be quite nice). If it is well filtered and clear, then the flavour will be pretty consistent until it starts to go sour or bad.


Aeropress: coffee starts flowing as soon as I flip it?

This will happen if you are using flavored coffee, if you're using too much water relative to coffee, or if your grind size is too large.

Flavored coffee causes this because a big portion of the "coffee grounds" are actually flavoring solids that dissolve in water. When you add water, those solids dissolve, and you're left with not enough coffee to hold back the water.

Too much water relative to coffee can cause this simply because of gravity. More water means more force pushing down on the coffee beans, and that means more water can get through.

Grind size too large is a likely cause. Your coffee simply might not be creating a cohesive barrier to water. Coarsely ground coffee will do this because the coarse grinds leave little gaps where the irregularly shaped grinds touch. Water can flow through those gaps. For Aeropress, you want a grind setting between drip and espresso.


What temperature to dry wet coffee grounds and for how long?

I wouldn’t attempt to dry wet grounds - the quality would likely suffer and for brewing they will be made wet again, which would make the drying step moot. Just use them straight from the fridge (as discussed in your other Q/As) and proceed as usual.

Now, beans are different. All preparations I am familiar with require the beans to be ground in one way or other. Pouring wet items in a grinder or mill designed for dry food will cause clumping, clogging and at worst damage your grinder.

Successful drying requires two things:

An environment with a low relative humidity and
good air flow around the objects that are to be dried.

So arrange your beans in a single layer on a rack or tray and find a “dry and windy” spot. The temperature can be even cool room temperature (dry surroundings and airflow are crucial, not temperatures), but may cooks prefer a low oven with the door slightly ajar. Up to 50 C won’t be a problem for the beans. Drying time depends on how wet the beans were - check on them regularly and turn them around on the tray.


What do the terms extraction and strength mean?

Though I don't generally like to cite Wikipedia as my primary reference, it does in this case have a pretty good overview of terms related to coffee extraction, re-summarized here:

Extraction:
The amount of the original mass of the grounds that ends up in the brewed coffee. Though it certainly depends on the preparation method ("method of extraction", e.g., drip, moka, espresso, cold-brew, ...), the recommended extraction amount is about 20% (i.e., about 20% of the mass of the beans/grounds ends up in the brewed coffee).

Less than ~15%-18% extraction is considered "under-extracted" and can be sour. That is, under-extraction is not just a matter of inefficiency: the result can be sour and unbalanced due to the fact that acids are extracted quickly. On the other hand, more than ~22%-25% extraction is considered "over-extracted" and can be bitter, because the bitter compounds are extracted later in the brewing process.

These figures were generated by groups with lofty-sounding names like the Specialty Coffee Association of America, the Coffee Brewing Institute, and the Italian Espresso National Institute. Also known as "solubles yield." See also this article on espresso extraction.

Strength:
The concentration of the extracted compounds in the water. Basically, how much coffee is in the water per unit (volume or mass).

As noted in the question, there are also colloquial or vernacular uses of these terms (e.g., "strength" as relative flavour profile; "extraction" as the process of brewing, etc.) but the above seem to be the accepted tangible definitions of the terms.


Best technique to make latte art with an Aeroccino 3?

Check this out https://youtu.be/X00xSAndJZU

I also find that the milk will be separated with the foam quite fast so you need to immediately pour the milk out of the can.
Shaking the can also help a lot as the milk will again emerge with foam and give silky result.


I run my espresso machine until my whole cup is full. What's my coffee called?

I'd say that it's a caffè crema which is generally made the way you make your coffee and is about 240 ml. It's about 3 times more water than a normale.


Difference between inverted and normal aeropress?

The differences are minor, but there are differences.  When brewing normally, water begins to drip through the paper filter immediately when poured over the grounds.  After stirring I usually have to add more water after the bloom recedes.  Inverted, all the water stays with the grounds until you flip it over and start extracting.  The extra water added with the normal process is hotter, and I believe will tend to over extract bitter notes more easily, not only because of the higher temperature, but by virtue of the added volume of water passing through the grounds.

Inverted, however, the volume of water is less, and because of that, the temperature of that water will be lowered a bit.  You can extract quickly, or wait as long as you want to extract the coffee.  Additionally, I have seen it claimed that with the inverted method, oils that will rise to the top of the column will be forced through the filter first and flavor the coffee more than with the regular method where they tend to get trapped in the grounds.

I have gone back and forth but always seem to go back to the inverted method. It provides more control of the variables and for me gives a better flavor, even when using the same beans, same roast, same water temperature.  Your mileage may vary of course.


What are some proven effective ways to set up a subscription program for one's coffee business?

I don't have experience with subscription programs, but I have looked at such programs. I think the following points should be addressed:

Freshness. This is a major selling point. If your deliveries are roasted over a month ago (or even less if you're doing (bi-)weekly deliveries), you lose a lot of the appeal. Why would customers bind themselves to your program if they can get as fresh to-order?
Reliability. Especially when you're doing more frequent deliveries (biweekly or even weekly) customers will rely on your delivery. That is, if I expect a delivery on Saturday, I won't stock other fresh coffee for the days after. So if your delivery runs late, I might run out (which is exactly what your subscription program should prevent).
Price. It has to be reasonably good value. In particular, you don't want to spend too much on shipping, as that means customers aren't getting good value for money. Obviously, as volumes per shipment get bigger this becomes less of an issue and as your programs serves a lot of customers you might get a better deal with the delivery companies.
Type of delivery. What I mean here is that the delivery should take little effort on the customer-end. For example, when I order beans they'll be delivered by someone ringing the door bell (because it's a big box), when I'm not home, they'll deliver to the neighbours or take it back. When you're sending small packages, make sure you customers don't need to be home, make sure it fits in / through the mailbox. That way, it will be there when they get home.
Payment. You probably want to offer a range of options. Some customers prefer to have a recurring payment that doesn't require them to authorise it for individual deliveries. Others like to pay per delivery or use pre-paid. Depending on payment options available in your country, you can offer a range of options.


Pressurized vs non pressurized filter baskets

You will need to grind a lot finer with the non-pressurised baskets.
With a pressurised filter basket, the resistance is mostly produced by the one tiny hole in the filter basket. For non-pressurised ones, the coffee needs to provide the resistance.
If the grounds fail to provide enough resistance, the water will run through the coffee really fast, probably creating a bunch of channels which you can usually see as little holes in the coffee bed after the extraction. The problem with the channels is that most of the water goes through the channels (over extracting the coffee there) instead of evenly extracting all available grounds.


I understand that the crema created by the Brikka is an approximated crema using the gasket's small opening. Sure, purists may not consider this tan, smooth film of microbubbles as authentic crema (akin to espresso makers), but it does do a good job creating it for a close mouthfeel.

I use my Brikka every day, and it creates the "Brikkrema" (as I'd like to call it) just fine [see the photo].

If you aren't achieving proper results, it could be the water, or the bean you're using. I've had instances where some beans wouldn't generate a great crema, as compared to other varieties. Factors could be the age, the containers their kept in, and all basically relating to the oils and the CO2 trapped in the bean shortly after roasting.

The last photo shows a comparison between pours. The first pour (left) often providing the most crema from a brew, while the subsequent pours (right) may not have as much. It helps to spread the first pour over each shot if you have more than one shot to serve, and then pour the rest of the coffee along the side of the cup as not to disturb the cream on top. Sometimes, a brand new Brikka needs 3-4 brews before it begins creating its magic. But even so, if you aren't achieving your preferred result, try these tips:

Try to lessen the water below the water line

start with a shot's worth of water then see what you get, then just increase to get a proportion you're happy with).

Try filtered water

you'd be surprised how big a difference water quality can make.

Change the bean you're using, until you get your desired results.

Some beans offer varying levels of crema, whether it's because of the CO2 content from the roast or just the overall nature of the bean.

Good luck! And don't worry, at the end of the day it boils (or brews) down to personal preference.