Autolysis? Infection? Hot Fermentation? Help!

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phuzle

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So, I'm not exactly new to brewing, been doing it for 8 years, but have only recently tried to become serious about it. Last fall I started washing yeast, making starters, and just this spring I went all grain. I still don't have any fermentation temperature control in place, but hadn't had any problems... until recently.

So last fall I bought WL california V yeast, aka the anchor strain. I like it, and I'd been washing it to put into a few mason jars after I racked out of my primaries. I used my last jar of the second generation of washing in a very hoppy extract pale ale. One thing to note is that quite a bit of hops fell into the fermenter when my helping friend got careless. I assume that isn't an important detail, but I wanted to add it.

That pale ale was my last extract, and then I moved to all grain. I harvested yeast from that pale ale for my first all grain, an american wheat ale. I should note that I had just bought fermometers. I noticed this batch got up to about 78 before I stuck it in my keg fridge for a few hours to bring it to 68. There was an unmistakable rotten egg smell for the rest of the fermentation, and the beer tastes pretty skunky. So whatever, I assume it is just the hot fermentation and the batch will either get better or it won't.

So I make my second all grain batch, a similar recipe but with a nice vienna presence. I use the same harvested yeast from the extract pale ale. I didn't see it get too hot, it never had a rotting smell, but the beer has a very similar flavor of skunk and isn't very enjoyable to drink.

I'm getting ready to brew another time, this time I harvested the yeast from the 2nd all grain batch. Made the starter, it fermented out, and the spent wort has that same awful smell and taste from the 1st all grain batch, and so I've pitched it an given up on my strain of Anchor yeast.

So my questions are: does this sound like a hot fermentation? I've been reading about hot fermentations, and this smell and flavor doesn't seem to be common of hot fermentations. Also, I was using this yeast all winter before I had the fermometer, when my house's ambient temperature was the same. So I have to assume that all my other delicious beers with this yeast were fermenting hot.

So is it autolysis? I've read that this is a likely cause of the rotten egg smell. But why, after re-washing and making a new starter, would I still have that awful smell and taste? It seems that all the new yeast cells would be far greater than the autolysing cells and I'd be fine.

How about an infection? It seems after a few generations, the bacteria could be built up enough to compete with the yeast cells. Or what about those hops that fell into the last good batch? Could the hop chemicals mess up the yeast? I still have a jar of this yeast left in the fridge, but I am scared to use it since they make beer smell revolting!

Edit: I should add, both batches had normal FGs and sat in primary for 16 days before kegging. I usually go about two weeks with all my batches and I've never had any problems before.
 
Well, if you know you have a problem with the yeast get rid of it. Washing yeast and tossing in the fridge gives you a little more time, but not something to do to store yeast for months on end. I agree though that if you re-washed and made a new starter dead yeast cells aren't your problem. I wouldn't worry about hops falling in, that's just more dry hops and hops do not impact yeast, they do inhibit a lot of other critters like lacto though (IIRC hops inhibit gram-positive bacteria).
 
It doesn't really sound like hot fermentation or autolysis. Maybe infection. Did you brew any good beers with that yeast? Did you make a starter? Did you taste it? I would switch to a new yeast. If the flavor sticks around you might start looking at your equipment for scratches, etc.
 
Well, thats just the problem. There are so many variables that I'm unsure if it is the yeast, the temperature of the fermentation, the new all grain equipment... I've made plenty of good beers with this yeast before going all grain, but that was also over the winter and done inside on my stove top.

I'll try a new yeast and see what happens.
 
Cal V isn't the anchor strain,
From Northern California. This strain is more fruity than WLP001, and slightly more flocculent. Attenuation is lower, resulting in a fuller bodied beer than with WLP001.
Attenuation: 70-75%
Flocculation: Medium to High
Optimum Fermentation Temperature: 66-70°F
(19-21°C)
Alcohol Tolerance: Medium-High

WLP810 san fran lager
This yeast is used to produce the "California Common" style beer. A unique lager strain which has the ability to ferment up to 65 degrees while retaining lager characteristics. Can also be fermented down to 50 degrees for production of marzens, pilsners and other style lagers.
Attenuation: 65-70%
Flocculation: High
Optimum Fermentation Temperature: 58-65°F
(14-18°C)
Alcohol Tolerance: Medium-High
 
Take a look at an off-flavor chart and see if you can nail down the flavor. Describing it appropriately will help nail down the cuase.

Given that you are changing so many things, if I were you I would try your next batch with US05 dry yeast. It's very forgiving and highly attenuating. This can help eliminate variables.

As far as other things, temperature control is a must. If you use a temp probe appropriately, a controller/frig or freezer set-up will regulate temp based on the wort temp, not ambient. Ambient plus 3-10 equals the true wort temp. And high temps will absolutely cause off-flavors.
 
The off flavor chart on Palmer's site doesn't seem to have what I'm going for. I'm pretty convinced that it can't be autolysis or hot fermentation, so it must be some kind of infection.
 
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