<p>I have had bags made up in China. 30cm x 30cm 100 micron is best for stepping. Put 5kgs of coffee in each bag and filter it a second time straight out of the tap.</p>

<p>Ohhhh and never squeeze the bags.</p>

CC BY-SA 3.0
2017-01-26T19:08:26.890Z
What are the bags made of? What do you mean about filtering a second time? Through a new bag, through the same bag again, or through paper or something else? If you're filtering a second time, why not squeeze the bag? Would you expand on these? It seems like an interesting idea, but more detail would help. Welcome to [coffee.se]!
hoc_age
CC BY-SA 3.0
2017-03-06T17:22:36.717Z
I'm also curious about squeezing the bags. I've spoken with coffee producers who squeeze/press in order to get every last drop of coffee out. I've also spoken with others who claim that squeezing the grounds will extract and yield off flavors that you don't want in your coffee.
brendo234
CC BY-SA 3.0
2017-01-23T07:21:08.017Z
2017-01-23T21:47:29.263Z
2017-01-23T21:47:29.263Z
Steve
<p>Have you looked into these <a href="https://www.coldbrewavenue.com/cold-brew-coffee-systems.html" rel="nofollow">stainless steel cold brew systems</a> at all? Reusable filter, no mesh bags to clean. Good for the environment and easy to use.</p>

CC BY-SA 3.0
2016-06-26T05:00:57.250Z
Yeah I have, I'd be interested to know how effective they are (probably a separate question). I can't imagine that the mesh is fine enough to get away with no secondary filtration. The main reason I passed them up is because of the size - we want to move to 1000 yield batches.
Tod
CC BY-SA 3.0
2016-06-23T23:01:10.510Z
2016-06-23T23:01:10.510Z
brendo234
<p>I've been testing out our latest releases (at the coffee company where I work) and found that I needed to brew them all in the same style to really compare the nuance of each roast. I decided to go with cold brew across the board, though I drink the resulting coffee both hot and cold.</p>

<p>I have had great results with <a href="http://coffeesock.com" rel="nofollow">the Coffee Sock</a> or on <a href="http://rads.stackoverflow.com/amzn/click/B00F8LVIYI" rel="nofollow">Amazon</a>, and I really enjoy its simplicity. I am only brewing in much smaller batches (a gallon at a time) but I wonder if that material would give similar benefits (no need for secondary filtration, good pass-through, durable, easy to clean) at a much larger scale?</p>

<p>Would love to hear your thoughts!</p>

CC BY-SA 3.0
2016-05-16T23:39:30.380Z
I haven't tried a coffee sock, and they don't seem to know what the pore sizes of their fabric are, however I'm guessing that they won't be in the <100 micron range so secondary filtration will still be necessary. Do you squeeze the sock?
Tod
CC BY-SA 3.0
2016-05-17T00:18:27.357Z
Welcome to [se]! I removed a link because of [guidelines on self-promotion](http://coffee.stackexchange.com/help/promotion) -- it's not relevant to your answer; for more, see about [answer] or take the [tour]. I also changed the product link to be to the product itself (I think) and to the SE-helping Amazon link. If I have mis-characterized your content, please modify again. Welcome!
hoc_age
CC BY-SA 3.0
2016-05-24T15:35:21.960Z
@Tod Sorry for the delay! I suspect my at-home method doesn't scale up as well as a mesh. You're right, secondary filtration is probably necessary. To answer your question though, it's not necessary to squeeze the sock (which, I suspect would pass through even more sediment). I leave it 12-18 hours then remove it and let it drain.
Robert1er
CC BY-SA 3.0
2016-05-12T19:03:08.513Z
2016-05-17T00:20:08.937Z
2016-05-17T00:20:08.937Z
Robert1er
<p>Have you considered a larger mesh than follow with a small centrifuge to polish out all the solids that go through the mesh?</p>

CC BY-SA 3.0
2017-04-01T22:38:13.847Z
Hi Mike, welcome to the site. Can you expand on your answer, as it is it's a little hard to follow.
fredley
CC BY-SA 3.0
2017-04-03T15:41:07.727Z
Mike, I second @fredley's comment.
Mayo
CC BY-SA 3.0
2017-03-31T02:15:31.120Z
2017-03-31T02:15:31.120Z
Mike Matthews
<p>You may want to <a href="https://wholesale.toddycafe.com/shop-item/110/Toddy%C2%AE+Cold+Brew+System+-+Pro+Series+20+-+US.php" rel="nofollow noreferrer">check this one out</a>. It's stainless steel, uses sanitary fittings and single use compostable filters. No cleaning filters required and they drain much better than the stainless mesh options in my experience. </p>

CC BY-SA 4.0
2018-05-03T03:20:57.493Z
2018-05-03T03:20:57.493Z
GCBrew
<p>I'm looking to upscale our production of cold brew to batches with a 1000L yield, using a ratio of 1:12.5 to make a ready-to-drink coffee for bottling. Currently we run batches of ~40L through a large stainless 40-micron mesh conical filter with good results, however this won't scale so easily as the mesh is really expensive. I'm thinking that making large batches by steeping coffee in big mesh tea bags will be the easiest upgrade. I'm also assuming that a secondary filtration will be necessary, but that's a separate question.</p>

<p>What sort of mesh sizes and materials are best for balancing yield with how fine the filtration is? 
Thanks! </p>

<equipment><cold-brew><filter>
Large scale cold brewing - Mesh bag technique - What size mesh is best?
Tod
# Large scale cold brewing - Mesh bag technique - What size mesh is best?

(Asked by: username_0 on 2016-05-08)

I'm looking to upscale our production of cold brew to batches with a 1000L yield, using a ratio of 1:12.5 to make a ready-to-drink coffee for bottling. Currently we run batches of ~40L through a large stainless 40-micron mesh conical filter with good results, however this won't scale so easily as the mesh is really expensive. I'm thinking that making large batches by steeping coffee in big mesh tea bags will be the easiest upgrade. I'm also assuming that a secondary filtration will be necessary, but that's a separate question.

What sort of mesh sizes and materials are best for balancing yield with how fine the filtration is?
Thanks!

**Tags:** equipment, cold-brew, filter


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## 5 answers

### Answer by username_1 on 2017-01-23. Score: 2

I have had bags made up in China. 30cm x 30cm 100 micron is best for stepping. Put 5kgs of coffee in each bag and filter it a second time straight out of the tap.

Ohhhh and never squeeze the bags.

> **Comments:**
> **username_2**: What are the bags made of? What do you mean about filtering a second time? Through a new bag, through the same bag again, or through paper or something else? If you're filtering a second time, why not squeeze the bag? Would you expand on these? It seems like an interesting idea, but more detail would help. Welcome to [coffee.se]!  
> **username_3**: I'm also curious about squeezing the bags. I've spoken with coffee producers who squeeze/press in order to get every last drop of coffee out. I've also spoken with others who claim that squeezing the grounds will extract and yield off flavors that you don't want in your coffee.  

---

### Answer by username_3 on 2016-06-23. Score: 1

Have you looked into these [stainless steel cold brew systems](https://www.coldbrewavenue.com/cold-brew-coffee-systems.html) at all? Reusable filter, no mesh bags to clean. Good for the environment and easy to use.

> **Comments:**
> **username_0**: Yeah I have, I'd be interested to know how effective they are (probably a separate question). I can't imagine that the mesh is fine enough to get away with no secondary filtration. The main reason I passed them up is because of the size - we want to move to 1000 yield batches.  

---

### Answer by username_4 on 2016-05-12. Score: 1

I've been testing out our latest releases (at the coffee company where I work) and found that I needed to brew them all in the same style to really compare the nuance of each roast. I decided to go with cold brew across the board, though I drink the resulting coffee both hot and cold.

I have had great results with [the Coffee Sock](http://coffeesock.com) or on [Amazon](http://rads.stackoverflow.com/amzn/click/B00F8LVIYI), and I really enjoy its simplicity. I am only brewing in much smaller batches (a gallon at a time) but I wonder if that material would give similar benefits (no need for secondary filtration, good pass-through, durable, easy to clean) at a much larger scale?

Would love to hear your thoughts!

> **Comments:**
> **username_0**: I haven't tried a coffee sock, and they don't seem to know what the pore sizes of their fabric are, however I'm guessing that they won't be in the <100 micron range so secondary filtration will still be necessary. Do you squeeze the sock?  
> **username_2**: Welcome to [se]! I removed a link because of [guidelines on self-promotion](http://coffee.stackexchange.com/help/promotion) -- it's not relevant to your answer; for more, see about [answer] or take the [tour]. I also changed the product link to be to the product itself (I think) and to the SE-helping Amazon link. If I have mis-characterized your content, please modify again. Welcome!  
> **username_4**: @username_0 Sorry for the delay! I suspect my at-home method doesn't scale up as well as a mesh. You're right, secondary filtration is probably necessary. To answer your question though, it's not necessary to squeeze the sock (which, I suspect would pass through even more sediment). I leave it 12-18 hours then remove it and let it drain.  

---

### Answer by username_5 on 2017-03-31. Score: 0

Have you considered a larger mesh than follow with a small centrifuge to polish out all the solids that go through the mesh?

> **Comments:**
> **username_6**: Hi Mike, welcome to the site. Can you expand on your answer, as it is it's a little hard to follow.  
> **username_7**: Mike, I second @username_6's comment.  

---

### Answer by username_8 on 2018-05-03. Score: -1

You may want to [check this one out](https://wholesale.toddycafe.com/shop-item/110/username_0dy%C2%AE+Cold+Brew+System+-+Pro+Series+20+-+US.php). It's stainless steel, uses sanitary fittings and single use compostable filters. No cleaning filters required and they drain much better than the stainless mesh options in my experience.


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