Grind quality and sour flavors?

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nuketopia
Posts: 1305
Joined: 8 years ago

#1: Post by nuketopia »

So, starting with a clean grinder and a known good, properly working espresso machine at 9 bar and 93c (200f) brewing temperature, properly mineralized water, dosing and grinding that will pull a double shot measured by weight in 25-30 seconds, can the *quality* of the grind cause sour flavors to increase?

If we hold the brewing parameters constant, and adjust dose/grind through the ranges that produce the expected weight of coffee in the expected time (say 1:2 brew ratio in 28-30s), is it merely the coffee itself that is the root cause? Or can the quality of the grind introduce sourness?

I've seen some presentations that propose that the amount of "fines" in the grind is the cause of this and that for the most part, the grinders we're all using are the cause of the fines, by design.

Any there any sense of the ratio of fines in espresso grinds affecting the final flavors of the brewed coffee, particularly in the sour notes?

jwCrema
Supporter ❤
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Joined: 11 years ago

#2: Post by jwCrema »


frank828
Posts: 302
Joined: 12 years ago

#3: Post by frank828 »

different grinders can definitely make the espresso taste different.

691175002
Posts: 89
Joined: 8 years ago

#4: Post by 691175002 »

nuketopia wrote:So, starting with a clean grinder and a known good, properly working espresso machine at 9 bar and 93c (200f) brewing temperature, properly mineralized water, dosing and grinding that will pull a double shot measured by weight in 25-30 seconds, can the *quality* of the grind cause sour flavors to increase?

If we hold the brewing parameters constant, and adjust dose/grind through the ranges that produce the expected weight of coffee in the expected time (say 1:2 brew ratio in 28-30s), is it merely the coffee itself that is the root cause? Or can the quality of the grind introduce sourness?

I've seen some presentations that propose that the amount of "fines" in the grind is the cause of this and that for the most part, the grinders we're all using are the cause of the fines, by design.

Any there any sense of the ratio of fines in espresso grinds affecting the final flavors of the brewed coffee, particularly in the sour notes?
I thought the general consensus was that smaller particles (such as fines) extract faster due to increased surface area, and would therefore make the coffee more bitter.

Baristahustle has some information on sifting and what happens with/without fines here: http://www.baristahustle.com/grindingthoughts/

Nick Name
Posts: 680
Joined: 9 years ago

#5: Post by Nick Name »

691175002 wrote:I thought the general consensus was that smaller particles (such as fines) extract faster due to increased surface area, and would therefore make the coffee more bitter.
+1

I was just about to say the same.

I wonder if there are boulders in the grind?