2 Small Flies Found in Yeast Starter: Pitch or Throw Away

[Brewmegoodbeer]

I just made me a nice yeast starter of Wyeast French Saison. When I went to put the flask in the fridge, I noticed 2 small flies in the starter. They somehow found their way through the foil cover and got in there. Should I forget about it and pitch the yeast (was planning on brewing tomorrow) or should I throw this away and go buy some new yeast? I am sort of a risk taker, but at the same time I don't want to waste the money I am spending on making this batch. The starter smells just like the yeast when I poured it out of the package into the flask at the beginning.

 

[AkTom]

Use it. Brew on!!! Be sure to squeeze all the yeast out of their nasty little throats.

 

[Brewmegoodbeer]

I dumped them out of the starter as soon as I found them. I keep reading that fruit flies carry actinobacteria which can turn fermenting wort into basically vinegar. Every forum I read about it has advice to throw out, but there has been a few examples in forums of people trying it and everything worked out fine. Maybe I'm feeling risky and wanting to say "what flies?" I suppose my saison can become more sour than intended!

a little off topic, but brewing outside, I've had a bug here or there fly into my wort before boiling whatever they got in my wort. I guess if anything, it was added protein.

 

[bigplunkett]

I wouldnt risk it. Flys can turn beer to vinegar or wine.

 

[flars]

You could delay brewing until next weekend. Let the starter sit at room temperature for a week to see if any signs of infection begin developing. I'm not sure if one week would be enough time for a pellicle to start forming though.

 

[foam_top]

As a risk taker, are you going to be mad at yourself in 4+ weeks if you have to dump a batch? It's possible the batch will be fine, it's possible that if it gets infected it may even be drinkable, but ~7 dollars now and a little patience will ensure it's a drinkable batch.

 

[brick_haus]

Well, I found one of those pesky beer flies in my starter for the current batch of Abbey Tripel that I currently have conditioning. At priming time, still tasting OK but time will tell... Good luck with yours!

 

[Dcpcooks]

If you plan to keg and drink quickly you'll probably be fine. If you want to cellar it you'll probably be sad. Yeast will most likely out compete any bugs in the short run but it doesn't take much acetobacter to spoil a beer longer term.

The bugs it could also be carrying like salmonella and E. coli won't survive once you have enough booze created.

Personally I'd toss it and just go buy a few new packs of yeast but lhbs is four blocks away.

 

[ten80]

Do you like malt vinegar??


You were essentially be doing an acetobacter starter. I have a friend who lets a few fruit flies into a carboy of cider on purpose to make 5-gallons of vinegar every few years. It's a nice thing when done on purpose.

 

[Hoppy2bmerry]

My thought is get new yeast. If it sours from the bacteria and crap flies eat you are losing not just the yeast, but all the ingredients and time you put into this batch.

 

[Brewmegoodbeer]

My lhbs is about 40 minutes away and $3.00 in highway tolls. I did 4 things:

1) I took the mason jar that had harvested yeast that was overbuilt from the yeast starter and I will be sitting at room temp for a week or two to see if it changes into vinagar (will not be using it either way).

2) I bought a foam stopper so this will never happen again

3) I made a Saison today and hit my gravity on spot.

4) I pitched the yeast. Before someone says "bad idea", I am well aware of the risk. I needed to brew today so I can rack to my keg before I go out of town next weekend (if fermenation is up to speed and I don't have vinagar)

I researched the internet on the fruit fly issue in starters for about 2 hours. Many say "don't do it" but don't have personal experiences. Many have done it anyways and their batch turned out fine. Very little that ive seen online actually tried it and it turned south. I am willing to take the "try it" route. Worst comes to worst, I learn a lesson and I become an advocate of saying "don't do it because I tried it and got 5.5 gallons on vinagar".

I have also read that this reaction to turn it into vinagar requires oxygen and a decent amount of time. I will be transferring to my keg taking steps to have virtually no oxygen exposure. I usually drink my kegs within a month or two so by the time actetobacter decides to want to work, I will be peeing it out in the toilet. ill update on what happens.

 

[Special Hops]

Ever come up on a pile of dog poop and see all the flies swarming off of it?

Think about it? Just saying....

 

[Brewmegoodbeer]

Ever come up on a pile of dog poop and see all the flies swarming off of it?

Think about it? Just saying....

Im sure I have consumed worse at restaurants. Ever used a public bathroom, washed your hands then touched the doorknob to the door before you went back to the table to eat? You likely had human fece germs on your hand. Im not saying this is best practice. Im more doing this to "go against the grain" (lol) to see if I can get away with it once. Cheers

 

[Brewmegoodbeer]

On second thought, maybe I should call it Against the Grain Saison lol

 

[Special Hops]

Im sure I have consumed worse at restaurants. Ever used a public bathroom, washed your hands then touched the doorknob to the door before you went back to the table to eat? You likely had human fece germs on your hand. Im not saying this is best practice. Im more doing this to "go against the grain" (lol) to see if I can get away with it once. Cheers

Yeah - But then I don't go on dipping these hands in my yeast starter.

 

[Weezy]

If you're kegging and it'll be gone in 1-2 months. Just go for it. If you're going to bottle condition and these are going to sit around for a while, including a bunch of time at room temp, is dump it.

I'm sure worse has ended up in beer we've drank!!!!

 

[betarhoalphadelta]

I had fruit flies hit a fermenting batch, not a starter. But I ended up with 15 gallons of vinegar.

Best of luck to you, though!

 

[brick_haus]

My lhbs is about 40 minutes away and $3.00 in highway tolls. I did 4 things:

1) I took the mason jar that had harvested yeast that was overbuilt from the yeast starter and I will be sitting at room temp for a week or two to see if it changes into vinagar (will not be using it either way).

2) I bought a foam stopper so this will never happen again

3) I made a Saison today and hit my gravity on spot.

4) I pitched the yeast. Before someone says "bad idea", I am well aware of the risk. I needed to brew today so I can rack to my keg before I go out of town next weekend (if fermenation is up to speed and I don't have vinagar)

I researched the internet on the fruit fly issue in starters for about 2 hours. Many say "don't do it" but don't have personal experiences. Many have done it anyways and their batch turned out fine. Very little that ive seen online actually tried it and it turned south. I am willing to take the "try it" route. Worst comes to worst, I learn a lesson and I become an advocate of saying "don't do it because I tried it and got 5.5 gallons on vinagar".

I have also read that this reaction to turn it into vinagar requires oxygen and a decent amount of time. I will be transferring to my keg taking steps to have virtually no oxygen exposure. I usually drink my kegs within a month or two so by the time actetobacter decides to want to work, I will be peeing it out in the toilet. ill update on what happens.

I have seen very little reporting on this matter based on real world experience. As mentioned in an earlier post, I had the same issue and went forward with the potentially contaminated pitch. It's not going to be life changing for me if it goes south, so what the heck? My Tripel is currently at the one week mark of keg conditioning at 70*f. I plan to age this 10% beer for a couple of months at 50*f after carbonation is complete.

Please post your real world experience and I will do the same, on this thread.

 

[Brewmegoodbeer]

I have seen very little reporting on this matter based on real world experience. As mentioned in an earlier post, I had the same issue and went forward with the potentially contaminated pitch. It's not going to be life changing for me if it goes south, so what the heck? My Tripel is currently at the one week mark of keg conditioning at 70*f. I plan to age this 10% beer for a couple of months at 50*f after carbonation is complete.

Please post your real world experience and I will do the same, on this thread.

Will Do Brick Haus! I am hoping we are both successful cases of this happening and it working out. I am taking measures for it to not happen again, so I am more doing it to be another +1 of people saying they went ahead and did it and nothing happened. If not, I'll be ok. Mad, but ok. lol

 

[Brewmegoodbeer]

UPDATE: After three weeks my Saison is on tap and tastes very good. No off flavors detected. It seems I slid by and got lucky! I had a mason jar full of the yeast that I overbuilt from the starter at room temp for 3 weeks and that too did not turn into vinagar. For those that this happens to in the future: if you live nearby your lhbs no harm done to get a new yeast pack but this is an example that you can get away with it! Cheers.

 

[kh54s10]

How many people open ferment. I am sure that a lot if not most of them have some contact with fruit flies or other critters.......

I would do as you did and use it in something that wasn't going to sit around aging for months and months.

 

[brick_haus]

I also promised an update on my fly "infected" starter.
I brewed my Tripel 4-1-17, a day after I found the fruit fly in my starter. Today is 5-25-17. I have two kegs of this beer.
Poured my first small sample today and ZERO off flavors![emoji106][emoji106]

View attachment ImageUploadedByHome Brew1495756338.175950.jpg

 

[brick_haus]

Just an update... 3 months and 15 days since I found the fruit fly in my starter. No sign of infection!