<p>No, when brewing via submersion, coarser grinds brewed longer will not produce the same flavors as fine grinds brewed shorter.</p>
<p>The reason why is penetration time. Water takes longer to infiltrate coarse grounds due to the power surface area vs fine grinds and the equal density. Because it takes longer, compounds extracted at the beginning of the brew sit in the hot water longer, and more undesirable compounds are extracted from the exteriors of the grounds.</p>
<p>This is actually the reason why finer grinds are preferred for Aeropress brewing. The water can quickly extract the flavors from most of the grounds with fine grinds, and the harsh, bitter flavors that are typical of other submersion methods (looking at you, French press) are avoided.</p>
<p>Hope this helps.</p>

CC BY-SA 4.0
2024-01-30T09:32:04.833Z
this is clear answer - thank you. It got me thinking about the material composition of a roasted bean and whether its uniform. I found this very nicely presented info that says it is.
https://handground.com/grind/an-intuitive-guide-to-coffee-solubles-extraction-and-tds
bobness
CC BY-SA 4.0
2024-01-30T12:54:36.027Z
Well no, like most things in nature, coffee is not uniform in material composition. However when you yourself grind coffee, unless you're sticking each little piece under some pretty fancy scanning equipment, you're not going to be able tell. Also lack of uniformity doesn't change what I said above. I mean, it might change the outcome of a particular brew, but it doesn't change the fact that increasing undisturbed immersion time and decreasing grind size together tend toward overextraction.
R Mac
CC BY-SA 4.0
2024-01-27T07:15:10.210Z
2024-01-27T07:15:10.210Z
R Mac
<p>when brewing, does more time with a coarser grind give the same flavour as less time with a finer grind? ie for a given flavour is it a simple proportional relationship of surface area to time, with some constant?</p>

<brewing-process><aeropress>
relationship of grind size to immersion time - aeropress
bobness
# relationship of grind size to immersion time - aeropress

(Asked by: username_0 on 2024-01-25)

when brewing, does more time with a coarser grind give the same flavour as less time with a finer grind? ie for a given flavour is it a simple proportional relationship of surface area to time, with some constant?

**Tags:** brewing-process, aeropress


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## 1 answers

### Answer by username_1 on 2024-01-27. Score: 1 | Accepted answer

No, when brewing via submersion, coarser grinds brewed longer will not produce the same flavors as fine grinds brewed shorter.

The reason why is penetration time. Water takes longer to infiltrate coarse grounds due to the power surface area vs fine grinds and the equal density. Because it takes longer, compounds extracted at the beginning of the brew sit in the hot water longer, and more undesirable compounds are extracted from the exteriors of the grounds.

This is actually the reason why finer grinds are preferred for Aeropress brewing. The water can quickly extract the flavors from most of the grounds with fine grinds, and the harsh, bitter flavors that are typical of other submersion methods (looking at you, French press) are avoided.

Hope this helps.

> **Comments:**
> **username_0**: this is clear answer - thank you. It got me thinking about the material composition of a roasted bean and whether its uniform. I found this very nicely presented info that says it is. https://handground.com/grind/an-intuitive-guide-to-coffee-solubles-extraction-and-tds  
> **username_1**: Well no, like most things in nature, coffee is not uniform in material composition. However when you yourself grind coffee, unless you're sticking each little piece under some pretty fancy scanning equipment, you're not going to be able tell. Also lack of uniformity doesn't change what I said above. I mean, it might change the outcome of a particular brew, but it doesn't change the fact that increasing undisturbed immersion time and decreasing grind size together tend toward overextraction.  

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