This is such a cool way to brew I think. Last night I transfered into two 5 gallon sankes and dry hopped one with 1 oz of Liberty and left it on the garage floor to warm back to 75*F'ish. The other keg I took home and hooked to the kegerator. Needs about another week cold in the kegerator to completely drop clear, but it looks like a bottle conditioned beer right now that the sediment has been stirred up in your glass. Another delicious beer at just 2 weeks old grain to glass. My roommate and I had about 3, and we really felt the 6.2%ABV kick in. No green taste at all, just a slight hint of yeast and a little more bittering coming through. The last two beers had the same increased bitterness, which I like, but it subdued in a week or more so I know my IBU numbers are correct now (I was really worried I was too bitter on the first beer). I really am starting to believe it does wonders for aging however, I need to remember next time to charge my kegs up to higher than fermenter pressure. I had a bit of a foam problem on the first keg I counter-pressure filled because I forgot I only had the kegs charged to 5psi. I cannot wait to try this out on a lager. I will get my chance the next refill on inventory I do in a week or two. Here is some good ester production information, I am finding a little more everyday. I am not using my system for anything other than ease of brewing for me, but reading about the science is also fun.
__________________ "Beer... Nutritious and Delicious!"
I read about pressure fermentation in a technical brewing book and it is indeed used for an accelerated fermentation at higher temperatures. The pressure helps to keep the byproducts in check that would usually become a problem at these temperatures. But since it retards yeast growth, the pressure should not be increased to early in the fermentation process. You may also keep in mind that yeast harvest can be a problem as the sudden depressurization, that happens when you open the keg to harvest the yeast, causes many yeast cells to die. They simply explode when the CO2 inside these cells goes out of solution. Commercial brewers harvest the yeast under pressure and slowly depressurize it. I don't think the fatality rate is 100% though.
But for most brewers, with a reasonable brewing procedure, neither diacetyl or esters are a problem. I never actually found diacetyl in my beer and think that it might be a problem that is overrated.
wortmonger, just keep playing with your system and see how the beer comes out with pressure during the primary fermentation and/or pressure build-up only at the end to aid racking the beer. Here is something on lager brewing: http://www.homebrewtalk.com/wiki/index.php/Fermenting_Lagers
the fermentation diagram (B) actually shows a pressure fermentation. Note the dot-dot-dash line, which shows the pressure.
Does the beer carbonate while it's fermenting under pressure?
Yes, this is why people add priming sugar to a bottling bucket before filling their bottles. You can take perfectly flat beer and do this to carbonate. It is called bottle conditioning, but means carbonated in the bottle. I ferment the entire way through using a little pressure and then seal it up tight a couple of gravity points from finishing to carbonate it to the level I want. This is different from everyone else in that they either force carbonate or bottle condition like I talked about earlier.
__________________ "Beer... Nutritious and Delicious!"
Yes, this is why people add priming sugar to a bottling bucket before filling their bottles. You can take perfectly flat beer and do this to carbonate. It is called bottle conditioning, but means carbonated in the bottle. I ferment the entire way through using a little pressure and then seal it up tight a couple of gravity points from finishing to carbonate it to the level I want. This is different from everyone else in that they either force carbonate or bottle condition like I talked about earlier.
Ok, Im not a complete noob, hehe
That's cool tho man, so after say...2 weeks your beer is fermented, carbed and ready to go???(Of course more time will let it condition more)
Yep, that's the theory and has seemed to be the case so far. 3 weeks grain to glass has been fantastic. Sorry, didn't mean to make you feel like a noob.
__________________ "Beer... Nutritious and Delicious!"
so anyone want to explain to me the advantages of pressurized fermentation?
From what I thought I picket up,
1 it takes less time to ferment
2, pressure holds back yeast growth
3, pressure keeps yeast from making organic compounds that taste bad
4, because the yeast can't make the fuesels, esters etc the beer doesn't need to be conditioned or aged and can be drank almost immediately. (and this is why large scale operations pressure ferment?)
From what I have seen on ales, yes on all accounts. I am about to try it with my first lager and see how she works out. I just find it easy to close everything up and only relieve pressure when needed. The beer comes out ready to drink and only needs a little more time to drop the remaining sediment. I also like how easy it is to take samples, not hydrometer samples though. The CO2 is a pain with the hydrometer and you have to wait forever so I use a refractometer as a reference only not a sure thing. After I am ready to drink the beer. I take the time to do a real degassed hydrometer reading. I just really like the system and hope it works for lagers too.
__________________ "Beer... Nutritious and Delicious!"
Linear Mode
