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Old 06-30-2011, 12:07 AM   #1
May 2011
plattsburgh, New York
Posts: 12

So last night I made a couple starters from two jars of washed yeast that I've had in my fridge for about 6 months. I was planning on brewing a few times over the 4th of July weekend since I haven't been able to brew in a long time (hence the 6 month old yeast). Both jars looked fine this morning, but when I got home from work one of them had small spots all over the top of it. I smelled both starters and they smell the same. Should I just assume that the one with the spots on top is infected and just chuck it out and get some new yeast to use this weekend? What about the other starter? Would you guys use it, or not?
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Old 06-30-2011, 12:16 AM   #2
Jan 2011
Fredericksburg, VA
Posts: 1,736
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Short answers : Yes it coudl be infected (looks probable to me) and No I'd dump it.

Longer answer:
Option one would be a cool pectile like you get in lambic brewing - don't count on being so lucky.
Option 2 is something like mold (which could either cure that sore throat, or kill you)
Option 3 is something of neither - perhaps some floating yeast colonies (I get that in longer brews/bottles, not sure about a starter) or perhaps some for of small air buble - looks like there are a few white spots on the right glass also.

Personally I'd not use it unless you have one of those 'I have a lb of DME and a 1 gallong jug, lets see what I can get' type opertunities.

with 6 month old yeast, there are plenty of things that could have gone wrong before now that advocate getting fresh yeast. I hope with the short time you have a nearby LHBS, although your location is rather remote

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Old 06-30-2011, 12:18 AM   #3
Jun 2010
Edmonton Ky
Posts: 1,335
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If they smell fine and not sour then I'd use it. Might even taste the wort on top but either way I would probabily use them if not sour or taste bad.
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Old 06-30-2011, 05:41 AM   #4
Dec 2010
Langley, BC
Posts: 934
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+1 to what the previous posters said, probably fine but a taste test will say for sure.

ACBrewer - There is NO WAY that the possible contaminated starter will kill the OP. Taste terrible? Sure, but not dangerous in any measureable way.

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Old 06-30-2011, 10:41 AM   #5
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Dec 2007
"Detroitish" Michigan
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It looks like simple yeast rafts to me. Like on the tops of beers in secondary that folks ALSO panic and think are infected when they are perfectly fine.

They look perfectly fine, I see no reason not to use them.

Tasting/smelling starters doesn't really tell you anything, unless you boiled the starter wort with some hop pellets, the unhobbed starter beer will start to sour within a few hours to a couple days. That doesn't mean there's anything wrong with the starter, it's just that unhopped beer will turn sour pretty quickly.

If you have no reason to believe the yeast is infected (i.e. improper sanitization practices for instance) then there's no reason to believe it would be infected.

You're pitching yeast and it's fermenting quickly, there's really no time for an infection to take hold.

Guys, I can't stress this enough, fermentation is usually ugly and smelly even when everything is fine a little bit of something on the surface, a funky smell, doesn't mean there's anything wrong. It is really hard to ruin your beer. Infections are NOT the norm, so expecting them to lurk under every corner is just not worth the hassle.

Try to assume everything is fine, not that you are one second a way from death and doom, because 99.99% of the time, EVERYTHING IS FINE!

If you've taken basic sanitary precautions, then there's nothing to stress out for.

Your yeast wants to work for you, it's dna is such that that is all it knows.

Since nothing pathogenic can exist in beer, you can take the idea of getting sick from anything we do in brewing, you can also take that option off the table as well.
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Old 06-30-2011, 01:16 PM   #6
Jan 2009
Pea Green, Colorado
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Originally Posted by Revvy View Post
. . . . They look perfectly fine, I see no reason not to use them. . . . . .
+1, they look normal.
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Old 06-30-2011, 01:47 PM   #7
Apr 2011
Morgantown, WV
Posts: 205
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Are the spots furry?

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Old 06-30-2011, 01:50 PM   #8
Feb 2009
Scarborough, Maine
Posts: 884
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Concur... They look fine, but...

It's your beer. If you are worried at all, then just buy some new yeast. Put your mind at ease and drop the extra $10 for a couple vials. Otherwise you'll wonder the whole time and certainly stress more than you need to.

That being said, I'd brew with it.

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Old 06-30-2011, 05:02 PM   #9
May 2011
plattsburgh, New York
Posts: 12

Thanks for the input everyone! With all of your reassurance I've decided to use the starters. I was just a little concerned because this was my first attempt at washing yeast, and I wasn't sure why one of them was getting the stuff on top and one wasn't. I'm sure the end product will be delicious one way or another!

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Old 06-30-2011, 07:18 PM   #10
Fich Eine Ente
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Mar 2010
Crestview, Florida
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Originally Posted by ACbrewer View Post
Option 2 is something like mold (which could either cure that sore throat, or kill you)

In this day and age, with all the literature available...

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