isomerization

[rasherb]

Can someone tell me if one of these is correct?

1. Hops go in boil
2. Alpha Acids become soluble and leave hops to go into wort
3. Alpha Acids Isomerize and contribute bitterness

or

1. Hops go in boil
2. Alpha Acids Isomerize
3. Isomerized AAs become soluble and leave hops to go into

I'm trying to determine if the alpha acids leave the hops at some point to some percentage then become isomerized in the wort to contribute bitterness or if the isomerization occurs while the AAs are still on the hops.

 

[dezman]

Can someone tell me if one of these is correct?

1. Hops go in boil
2. Alpha Acids become soluble and leave hops to go into wort
3. Alpha Acids Isomerize and contribute bitterness

or

1. Hops go in boil
2. Alpha Acids Isomerize
3. Isomerized AAs become soluble and leave hops to go into

I'm trying to determine if the alpha acids leave the hops at some point to some percentage then become isomerized in the wort to contribute bitterness or if the isomerization occurs while the AAs are still on the hops.

Good question had to look this up so i take no credit for this answer. "Alpha acids go into solution only after boiling isomerizes them to iso-a-acids." so i'm assuming that means your second idea is correct. Got this from Noonans Brewing Lager Beer

 

[rasherb]

Great! I Really wanted to know if pulling out hops from the boil immediately stops their bittering contribution or if their AAs linger in the wort being isomerized. I think this solves it.

 

[remilard]

I would guess that alpha acids go into suspension almost immediately such that if you remove the vegetal hop mass there are still un-isomerized alpha acids in the wort that would then isomerize and go into solution as you continue to boil.

 

[rasherb]

Okay. So what remilard said seems to suggest that youcan pull the vegital matter out at some point before 60 min, but still get all the bittering of a 60 min boil?

 

[day_trippr]

Okay. So what remilard said seems to suggest that youcan pull the vegital matter out at some point before 60 min, but still get all the bittering of a 60 min boil?

I agree that's what he's suggesting.

Cheers!