Author Topic: Slooooooooooooow primary fermentation - Tough one  (Read 4793 times)

Offline jobard

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Slooooooooooooow primary fermentation - Tough one
« on: July 10, 2015, 08:48:45 AM »
Hi, I'd like to share my failed experience with you all; perhaps this may have happened to you too.
I've brewed my second 4.5 gal. batch some time ago: an American Pale Ale. The whole brewing process was fine. I didn't make any big mistakes, except for not soaking the dry yeast in water before putting it into the fermenter with the wort. I did this way with my first batch, a Düsseldorf Altbier, and it turned out great, so I thought I wouldn't have any problems repeating the process, but I was wrong.
Many hours after tossing the yeast directly into the wort in the fermenter, there was no airlock activity whatsoever. After a couple of days of apparent inactivity, I added some half of a sachet of another yeast I had in my fridge (again, just threw it directly in the fermenter). Nothing happened. Then I bought a bread and pizza dough yeast, but this time I let it hydrate for about 15 min before putting it in the fermenter. Still nothing. Then I bought another beer dry yeast sachet, hydrated it and added in the fermenter. Still no activity, but during all these actions I was tasting the beer, and realized some attenuation.
I bought a refractometer and noticed that after almost a month of "fermenting", the scale read 7 Brix.
I decided to open the fermenter and give it a stir, and found a layer of mold. That white, bubbly, silky one.
On bottling day I simply avoided passing the mold to the bottle, and got rid of some beer.
The fact is: after 10 days of carbonation I opened one bottle and poured it in a glass. The head had a great creamy look, but it didn't last long, fading completely after a minute or two. Regarding the taste, it was watery (maybe a little bit like the Belgian Kwak), and tasted a lot like yeast - maybe because I used 3.5 times more yeast than needed.
Things to consider:
- the fermenting temperature varied a bit, from 40 to 64°F
- fermenter lid was not totally sealed (I had to use silver tape)

What could have caused the poor results?

Thanx, and sorry for the long post.

Offline brewfun

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Re: Slooooooooooooow primary fermentation - Tough one
« Reply #1 on: July 10, 2015, 10:46:43 AM »
What could have caused the poor results?

How much time you got? There are hundreds of things that *could* cause an apparently sluggish fermentation. One issue is the low fermentation temperature you described; 40 to 64F, too cold for most ale yeasts.

However, my first question is, "Did you use a bucket for fermentation?"  Some of your description suggests that you did and those things are notorious for leaking around the lid seal. Basically, fermentation happened, but wasn't vigorous enough to bubble the airlock because the CO2 escaped through the lid seal.

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I added some half of a sachet of another yeast I had in my fridge (again, just threw it directly in the fermenter).

Once a yeast packet is open, use all the yeast. It doesn't get any better with storage. A sealed package is sanitary, but once opened, all bets are off.

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Then I bought a bread and pizza dough yeast, but this time I let it hydrate for about 15 min before putting it in the fermenter. Still nothing.

Probably a lot of something, I would think. Most bread yeasts have enzymes that'll break down starches and complex sugars that beer yeast can't touch. Bread yeasts tend to activate in minutes and work quickly.

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...during all these actions I was tasting the beer, and realized some attenuation.
I bought a refractometer and noticed that after almost a month of "fermenting", the scale read 7 Brix.

Opening the fermenter and fondling the beer should be a crime. It traumatizes the beer and wrecks your plans for the evening as you wonder if you'll get away with it.

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I decided to open the fermenter and give it a stir, and found a layer of mold. That white, bubbly, silky one.

Don't fondle the beer!

I don't think what you saw was mold. Aerobic molds don't like active fermentation and almost never happen in beer. That was probably a pellicle, which is a white or off white, sticky and often gummy cover on top of the beer. It's formed by some yeasts and many bacteria as a barrier against other microbes falling into the beer.  A lot of brewers see pellicles form when making sour or wild beers.

It could've come from the bread yeast (but likely not) or it could be a sign of other contamination. On the plus side, left alone for a year or two and it could turn into a very lovely sour ale of some kind. Or it could become a lifetime supply of malt vinegar. It's a win-win, if you really like fish.  ;)

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The fact is: after 10 days of carbonation I opened one bottle and poured it in a glass. The head had a great creamy look, but it didn't last long, fading completely after a minute or two. Regarding the taste, it was watery (maybe a little bit like the Belgian Kwak), and tasted a lot like yeast - maybe because I used 3.5 times more yeast than needed.

Again, keep it in a cool, dark place and just let it sit for a year, then try it.

Try again and use a fresh packet of yeast. Not rehydrating isn't totally bad, but it can cause a 50% mortality rate from the osmotic pressure of the wort. Then, keep the fermentation temperature between 66 and 74F.

Finally, just look for a krausen ring above the liquid line. This is a sign of healthy fermentation. There is no need to fondle the beer.
Beer Appreciation is the space between pints.

Offline jobard

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Re: Slooooooooooooow primary fermentation - Tough one
« Reply #2 on: July 10, 2015, 05:04:59 PM »
Thank you very much for your help, Brewfun. It does make a lot of sense.
Let me answer your questions:
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How much time you got?
30 days of fermentation, plus 10 days of carbonation and maturation.
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Did you use a bucket for fermentation?
Yes. Not many glass jars are available here in Brazil. In terms of homebrewing, we're still a crawling baby, whereas you're fully grown.
Right now I'm fermenting an extract Belgian Kriek lambic, and again, the airlock was totally idle. I believe I'll have to:
Buy new lids, or;
Find a glass jar to buy.
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Opening the fermenter and fondling the beer should be a crime
I plead guilty Your honor, but I promise you that will never happen again.
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it could become a lifetime supply of malt vinegar. It's a win-win, if you really like fish
Sorry, I didn't get that. Are you saying that malt vinegar goes well with fish?
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just look for a krausen ring above the liquid line
Yep, it was there. As a matter of fact, a few hours after pitching the yeast for the first time I raised the fermenter lid a little, just to take a peek. Although there was a lot of foam, the airlock was still (already explained by the pressure leak). I think I got a little anxious after that and just threw everything I had to speed up the fermentation.

I definitely learned from my mistake, and I will patiently wait till mid 2016 to open another bottle and see if I accidentally brewed my favorite all time beer: Bacchus. 
This will be an exercise, since I have a 2013 Fuller's Vintage Ale, whose "best" tasting day is Dec. 31st, 2023!  :o

Cheers!  ;D

Offline brewfun

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Re: Slooooooooooooow primary fermentation - Tough one
« Reply #3 on: July 11, 2015, 12:06:54 AM »
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it could become a lifetime supply of malt vinegar. It's a win-win, if you really like fish
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Sorry, I didn't get that. Are you saying that malt vinegar goes well with fish?

Quite well! It's delicious.
Beer Appreciation is the space between pints.

Offline Mofo

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Re: Slooooooooooooow primary fermentation - Tough one
« Reply #4 on: July 11, 2015, 11:04:04 AM »
Don't fondle the beer!

I'm a beer fondler. Learning not to touch it is difficult. A good fix is to pitch yeast, aerate, then fill a beer bottle or hydrometer cylinder with a single sample (use a sanitized wine thief to do so). Plug it with gauze and keep it next to your fermentor. Any time you want to take a gravity reading or pour a sip, take it from your sample, not your fermentor. You'll still want to practice good hygiene to avoid infecting your sample, but you'll dramatically reduce your chances of infecting your beer.
« Last Edit: July 11, 2015, 11:36:11 AM by Mofo »
bottled: Wee Heavy, Belgian Wit
fermenting: Imperial IPA, Citra Pale Ale

Offline Maine Homebrewer

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Re: Slooooooooooooow primary fermentation - Tough one
« Reply #5 on: July 11, 2015, 11:27:15 AM »
Beer battered fish with fries, dipped in malt vinegar. Now I'm hungry.
"To alcohol! The cause of - and solution to - all of life's problems!" -Homer Simpson