Hi All!
Got a question that I really need some help answering I feel like I'm really missing 'that' link that'll help me understand this infinitely better!
The Issue
How does aroma 'scrubbing' and beer foam specifically work and why is it not an issue when carbonating a beer through a carb stone with no head pressure in tank?
My Current Understanding of 'Aroma Scrubbing' and Beer Foam
Beer foam is primarily caused by LTPs (lipid transfer proteins) leaving the solution(beer). LTPs are hydrophobic so when CO2 rises through beer they attach themselves to the bubble and bring themselves to the surface and therefore out of solution of the beer (beer foam). My current understanding is (and I can't find any paper that suggests otherwise) that once the LTPs have found their way out of solution they can no longer be reintroduced into the beer.
Similarly, hop aroma compounds from dry hopping etc are in solution too and they too are hydrophobic meaning they will attach themselves to a CO2 bubble and break out of solution. Once again once these compounds are out of solution they cannot be reintroduced back into solution!?
The Issue - Specifically
So when carbonating through a carb stone into a tank with no head pressure with my current understanding it would mean you are in fact 'scrubbing' aroma and beer foam from your beer as most of the CO2 you are bubbling the beer with exits the solution and occupies the head space (hence the equilibrium head pressure) in this head space is there valuable aroma and beer foam compounds out of solution that cannot be forced back in?
The current understanding seems to be if you carbonate 'too quickly' through the carb stone this will cause beer foam and aroma 'scrubbing' but I cannot see how the vigour of the bubbles specifically causes this and how slowing the volume of CO2 would not cause these hydrophobic compounds to leave solution - especially if the head pressure rises from 0 to X PSI meaning the CO2 that has gone through the beer is in the head space.
To my current understanding just because the beer doesn't foam quickly (causing visible foam) it doesn't mean the compounds that cause foam are not out of solution. I am proposing that the same quantity could be out of solution but because they are taken out of solution slowly they do not appear to cause foam in tank.
Thanks for anyone who made it through!
Any links to good quality papers ALWAYS welcome as they are rarer than a clear beer in London!
Chris
Got a question that I really need some help answering I feel like I'm really missing 'that' link that'll help me understand this infinitely better!
The Issue
How does aroma 'scrubbing' and beer foam specifically work and why is it not an issue when carbonating a beer through a carb stone with no head pressure in tank?
My Current Understanding of 'Aroma Scrubbing' and Beer Foam
Beer foam is primarily caused by LTPs (lipid transfer proteins) leaving the solution(beer). LTPs are hydrophobic so when CO2 rises through beer they attach themselves to the bubble and bring themselves to the surface and therefore out of solution of the beer (beer foam). My current understanding is (and I can't find any paper that suggests otherwise) that once the LTPs have found their way out of solution they can no longer be reintroduced into the beer.
Similarly, hop aroma compounds from dry hopping etc are in solution too and they too are hydrophobic meaning they will attach themselves to a CO2 bubble and break out of solution. Once again once these compounds are out of solution they cannot be reintroduced back into solution!?
The Issue - Specifically
So when carbonating through a carb stone into a tank with no head pressure with my current understanding it would mean you are in fact 'scrubbing' aroma and beer foam from your beer as most of the CO2 you are bubbling the beer with exits the solution and occupies the head space (hence the equilibrium head pressure) in this head space is there valuable aroma and beer foam compounds out of solution that cannot be forced back in?
The current understanding seems to be if you carbonate 'too quickly' through the carb stone this will cause beer foam and aroma 'scrubbing' but I cannot see how the vigour of the bubbles specifically causes this and how slowing the volume of CO2 would not cause these hydrophobic compounds to leave solution - especially if the head pressure rises from 0 to X PSI meaning the CO2 that has gone through the beer is in the head space.
To my current understanding just because the beer doesn't foam quickly (causing visible foam) it doesn't mean the compounds that cause foam are not out of solution. I am proposing that the same quantity could be out of solution but because they are taken out of solution slowly they do not appear to cause foam in tank.
Thanks for anyone who made it through!
Any links to good quality papers ALWAYS welcome as they are rarer than a clear beer in London!
Chris
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