<p>The roasting process leads to water loss in all types of beans. Most beans start off at about 10-12% moisture and end up around 3%.
My experience gives about 15% weight loss (shrinkage) for light roasts and around 20% on dark roast profiles.</p>

<p>Example of a dark roast weight loss in my roasterie would be: 
Starting weight: 240#
Roasted weight: 195#
Shrinkage = 195/240 = 81% of start weight so 19% loss.</p>

<p>I can't seem to find any online documentation of this. Just daily experience of being a professional roaster.</p>

CC BY-SA 3.0
2017-01-29T02:51:00.527Z
Thanks so much.im planning to start a small coffee roasting business and been studying.
BigM
CC BY-SA 3.0
2017-01-29T07:27:23.240Z
@BigM, I was about to say around 20% for regular roasts. When it's not too light or too dark. Of course roasterbob has much more experience, he already gave a nice answer.
MTSan
CC BY-SA 3.0
2017-01-31T23:39:54.737Z
My experience with Ethiopian natural processed beans is right at 15%.  That's for a medium roast level.
PJNoes
CC BY-SA 3.0
2017-02-01T19:06:11.900Z
Volume also expands with darker roasts expanding the beans more. Almost like puffed rice or something.
Nathan
CC BY-SA 3.0
2017-02-01T23:24:36.987Z
@PJNoes, Ethiopian naturals tend to have less shrinkage because they tend to start off with a lower moisture content. So by that fact that have less moisture to lose from the get go no matter what roast level
roasterbob 
CC BY-SA 3.0
2017-05-24T17:02:50.350Z
I typically get 15% weight loss on most of my roasts and they are roughly a city / city+ roast.  Have seen as high as 18%, and have a few beans that drop only 12%.  That 12% run really worried me for a while, but it's one of our most popular coffees so.. I let the cup decide.
Nate M.
CC BY-SA 3.0
2017-01-29T00:19:47.617Z
2017-01-29T00:25:18.537Z
2017-01-29T00:25:18.537Z
roasterbob 
<p>I roast in a bread machine with a heat gun. I roast 567 g per batch (1.25 #). I roast Ethiopian and Kenyan beans. My weight loss is between 12.7% and 16.2% loss.
I end the roast at about 210 C (410 F) in about 10 to 12 minutes. If the batch weights in at 500 grams, I delay the cooling until it reaches about 490 grams usually 2 to 3 minutes. Then proceed to stop the roast. Usually the batch will weigh 488 grams which is a city+ for me. My "fireside chat" on Youtube The trout doc has details of process. SH</p>

CC BY-SA 3.0
2017-05-23T23:06:54.057Z
2017-05-23T23:06:54.057Z
TheTroutDoc
<p>i roast 2kg Colombian beans at a time (last batch begin 2003g) and end up around 1.6kg (last batch end, chaffed and cooled 1608g) i roast in an oven so need to remove chaff manually (i use a cool hairdryer, fan and a large bowl) so i ended up with a 19.72% reduction (moisture and chaff loss) (1608x100):2003=80.279% so yeah 20% loss for a medium roast, after first crack and before 2nd crack. been cracking beans for over 10 years now. love life love coffee</p>

CC BY-SA 4.0
2020-09-18T06:44:30.690Z
2020-09-18T06:44:30.690Z
John
<p>Does the roasting process lead to weight reduction? If so, what are determining factors? type of coffee? type of roast(dark, medium etc) ? </p>

<p>If you have X lbs of unroasted coffee beans, how much (average) roasted coffee beans you get after roasting?</p>

<roasting>
How much weight reduction occurs after roasting coffee beans?
BigM
# How much weight reduction occurs after roasting coffee beans?

(Asked by: username_0 on 2017-01-28)

Does the roasting process lead to weight reduction? If so, what are determining factors? type of coffee? type of roast(dark, medium etc) ?

If you have X lbs of unroasted coffee beans, how much (average) roasted coffee beans you get after roasting?

**Tags:** roasting


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## 3 answers

### Answer by username_1 on 2017-01-29. Score: 8 | Accepted answer

The roasting process leads to water loss in all types of beans. Most beans start off at about 10-12% moisture and end up around 3%.
My experience gives about 15% weight loss (shrinkage) for light roasts and around 20% on dark roast profiles.

Example of a dark roast weight loss in my roasterie would be:
Starting weight: 240#
Roasted weight: 195#
Shrinkage = 195/240 = 81% of start weight so 19% loss.

I can't seem to find any online documentation of this. Just daily experience of being a professional roaster.

> **Comments:**
> **username_0**: Thanks so much.im planning to start a small coffee roasting business and been studying.  
> **username_2**: @username_0, I was about to say around 20% for regular roasts. When it's not too light or too dark. Of course username_1has much more experience, he already gave a nice answer.  
> **username_3**: My experience with Ethiopian natural processed beans is right at 15%.  That's for a medium roast level.  
> **username_4**: Volume also expands with darker roasts expanding the beans more. Almost like puffed rice or something.  
> **username_1**: @username_3, Ethiopian naturals tend to have less shrinkage because they tend to start off with a lower moisture content. So by that fact that have less moisture to lose from the get go no matter what roast level  
> **username_5**: I typically get 15% weight loss on most of my roasts and they are roughly a city / city+ roast.  Have seen as high as 18%, and have a few beans that drop only 12%.  That 12% run really worried me for a while, but it's one of our most popular coffees so.. I let the cup decide.  

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### Answer by username_6 on 2017-05-23. Score: 3

I roast in a bread machine with a heat gun. I roast 567 g per batch (1.25 #). I roast Ethiopian and Kenyan beans. My weight loss is between 12.7% and 16.2% loss.
I end the roast at about 210 C (410 F) in about 10 to 12 minutes. If the batch weights in at 500 grams, I delay the cooling until it reaches about 490 grams usually 2 to 3 minutes. Then proceed to stop the roast. Usually the batch will weigh 488 grams which is a city+ for me. My "fireside chat" on Youtube The trout doc has details of process. SH


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### Answer by username_7 on 2020-09-18. Score: 3

i roast 2kg Colombian beans at a time (last batch begin 2003g) and end up around 1.6kg (last batch end, chaffed and cooled 1608g) i roast in an oven so need to remove chaff manually (i use a cool hairdryer, fan and a large bowl) so i ended up with a 19.72% reduction (moisture and chaff loss) (1608x100):2003=80.279% so yeah 20% loss for a medium roast, after first crack and before 2nd crack. been cracking beans for over 10 years now. love life love coffee


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