I did my first home brew and it ended up bubbling through the airlock...I cleaned it put it back on and it bubbled for awhile now i'm on day 4 of fermentation and no bubbles are coming up through the airlock. I'm assuming the yeast is good because of if bubbling to begin with.
Fermenting stopped early?
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Your yeast have just started into phase 3 of fermenting. During this phase they break down intermediate compounds that become alcohol without giving off CO2. Leave it alone for another 2 weeks and then use your hydrometer to test if it really is done. Try a second sample 2 or 3 days later and if the samples have the same reading you can bottle it.
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Interesting. I've never read that alcohol was produced during the stationary phase. Just the diacytly is reabsorbed and hydrogen sulphide goes out the airlock. I'll have to do some searching to find more. Got any links to share?
I think it's just semantics.............
After active fermentation there is still some fermentation occurring but at a much slower rate so yes, there is still alcohol being produced until the beer actually reaches final gravity but it is usually just the last few points and then the cleanup phase truly begins as the beer drops bright.
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I'm sure you're right. There must be some overlapping of the phases. I just never heard anyone say that before.
During the first phase, the yeast are using up the oxygen to reproduce. This is usually called the lag phase because it appears that nothing is happening. Phase 2 is where the yeast go crazy, eating the malt sugars and excreting alcohol and CO2. This is often called the active phase. While the yeast are primarily making the alcohol and CO2, there are a number of other compounds produced then too, on of which is acetaldehyde. During the third phase, this acetaldehyde is reduced to alcohol by the yeast but there is no CO2 being produced so many brewers assume that the ferment is over. This acetaldehyde is what gives beer the "green apple" or "cider" aroma. This process takes some time so we tell people not to rush to bottle. The yeast also break down or absorb other compounds that give "off flavors" so it is sometimes called the cleanup phase.
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Another new one to me. I've read in the past that aldehydes are carried off by CO2.
Nothing. A hydrometer is the instrument needed.
guess a refractometer would work as well, as long as the readings are stable, but they cost about ten times more than a hydrometer so many people don't have them handy.
Yes, you could. That might be an indicator, although not actual proof.
If someone bottles at that point, they can then hope that it really was done, and will not start up again in the bottle so the bottles won't blow up.
They might not, but they might. There is only one way to really know for sure, and that's via hydrometer readings.
A hydrometer is pretty much a necessity. If you can buy the ingredients for beer, those stores carry hydrometers as well.
Bottles blowing up in my house would suck, so it's not something I play around with.
Best advice is just to buy one--they cost like $5
If you have a serious aversion to them though, I suppose you could just give it 3 weeks and hope it didn't stall or anything. This is really asking for trouble though since it will give you sweet beer and bottle bombs if it didn't finish for some reason.
If you have a serious aversion to them though, I suppose you could just give it 3 weeks and hope it didn't stall or anything. This is really asking for trouble though since it will give you sweet beer and bottle bombs if it didn't finish for some reason.
I have another question...when it had bubbled up through the airlock it left a film on the upper inside of the carboy...did that need to be scraped back into wort or is it still ok? I'm not getting any bubbles in my airlock at all.
PandaBrau said:
That would be krausen and no it did not need to be scraped back in at all.
Bubbles don't mean anything, especially if you removed the lid as you released all the interior pressure that built up.
