How long should you/can you let a beer ferment?

Question

I have the Mr. Beer kit and am fermenting a honey Oktoberfest beer right now. It has been fermenting for 10 days so far, in the "keg". How long is TOO LONG for the beer to ferment before I bottle it?

Answer 1

You're right, with just a little bit more cost & effort, you can get much higher quality beer than brewing with Mr. Beer kits, but as an introduction to brewing, I hope you have a blast with it. Regarding your question- You're going to be utilizing only one stage of fermentation before bottling - primary fermentation. I would reccomend 3 weeks in primary before bottling, especially for a beginner.

- Plastic is oxygen permeable, and over 4 weeks you will start to oxyzidize your beer, that is, oxygen molocules will enter through the plastic & react with your beer, creating off flavors. Glass & Stainless Stell vessels do not have this problem.

- After about 4-5 weeks of dormancy, yeast will begin a process called autolysis. Put simply, this is the yeast turning inside out & spilling it's guts all over the place. It takes a while, but a true autolysis problem will rear it's head in the form of rubbery & rotten meat like aromas/flavors. Not good stuff.

- After about 4 weeks, the sediment you see on the bottom of your vessel will actually begin producing soap. Intersting, but true- the fatty acids left in the trub (a composite of proteins/grain material from the extract) will begin to leach out and flavor your beer. Now, you won't actually prdoce sudsing or a bar of soap at the bottom of your vessel, but the same checmical compounds are made.

- Fusel alcohols (higher level alcohols) can be created when the yeast sits too long on the trub. These alcohols taste "hot," like a cheap tequila and contribute to headaches.

-So why chance any of the above and let your beer go any longer than a week? Well, for one, you want to be 100% sure that all the available sugars have been eaten by the yeast before bottling. If not, you can create a dangerous situation when there is too much suagr for the yeast to eat in the bottle and they produce too much CO2- boom! For most ales, this is after 1-2 weeks, but in lagers, such as yours, it is 3-4 weeks. Although, I doubt you have an actual lager yeast strain- you'll have to check what your yeast packet said.

-After the yeast is done fermenting, they still are working to make your beer taste good. Chemical compounds like Acetaldehyde & Diacetyl can produce nasty off flavors in young beers & are common by products of fermentation. Given a couple weeks after fermentation is complete, the yeast will do away with most of these compounds.

-The longer wait will help to clarify your beer.

So the short answer is- 3 weeks.

Answer 2

10 days to 3 weeks. Check the keg and if the liquid is clear with very few floaties on top of the liquid it may be ready. You can drain a small amount out and taste it at this point. If it tastes like flat beer, fermentation is complete and you are ready to bottle. If it tastes sweet let it ferment a few more days.

Answer 3

Most recipes I have used require two weeks for the primary ferment. Some required three weeks. You have to carbonate in the bottles under any circumstances, otherwise you will have flat beer.

Answer 4

Just so you know, Mister Beer kits are low end beer kits. If you like brewing, you should locate a local homebrew supply store and upgrade to a real homebrewing kit.

Since you are dealing with a plastic fermenter, I wouldn't let it go more than two or three weeks.

Answer 5

Mr Beer American Light

Answer 6

a few factors play a role here... dry yeasts actually finish fermentation rather quickly... say 3-5 days.. leaving it longer(6-20 days wouldn't hurt, and may actually clean up off flavors, but I find that following some simple rules speeds things up but ensures a good tasting beer, and personally think that most of the off flavors are more than enough cleaned up after 7-8 days and more than that is overkill... PROVIDED you do a diacetyl rest to ensure strong/late yeast activity in the last .05-.08 specific gravity drop of fermentation). but you need to look at the yeast packaging to get an idea of the proper fermenting temperatures... pushing the low-end will make the process take a little longer... pushing the high-end, a little shorter... BUT you would still need to do a 'diacetyl rest' if you're rushing things... my advice... ferment close to the bottom end of the temp range on the packet... so if it says 55-72 degrees... ferment at say 58-60 for 6 days.... then ferment another 24-36 hours at 70... then cold-crash(about 38-40 degrees/throw on ice) for another 24 hours... then bottle... I think pushing into the 3 week territory is just silly... UNLESS you're lagering(cold fermenting - a process reserved for experienced brewers)..

Answer 7

Hey i'm here for the first time. I came across this question and I find the replies truly useful. I hope to offer something back to the community and help others too.

Answer 8

This has already been answered