The war is on fruit fly!!

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oceanic_brew

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Had about 800 billion yeast cells propagated up for a Dopplebock. Look inside and there's a fruit fly taking a dip.

Luckily I had two containers of washed lager yeast left in the fridge but I'm afraid it won't be near enough.

Still gonna be delicious! More fruit fly traps tomorrow.
 
Here's a question: with as many cells as you had, would there really have been an infection?

My son is a microbiologist and I've asked him about these kind of things. I've asked him, for instance, about wild stuff floating into my kettle as it cools, or stuff drawn into the fermenter when I take a gravity reading.

His response is that, yes, stuff is going in. It's almost a certainty. But there are so many yeast cells going that whatever does happen to get in is outcompeted by the yeast in a hurry.

I'm not saying that you should have pitched it, but rather I'm raising the question as to just how much contamination is needed to spoil a batch. Certainly the safe thing was to not pitch it, but I wonder just how much risk there is, given the number of cells you had.
 
BreakingPym1.jpg
 
Problem is, the lil bastards carry, among other things, acetobacter. Vinegar, anyone? While one lone fly might not carry much, it seems...a couple of aceto cells can be all that's needed to ruin a batch. Or at least make 5 gallons of condiment for fish-n-chips...:mug:
 
Here's a question: with as many cells as you had, would there really have been an infection?

I say it's still a possibility. That is how infections occur. My understanding of acetobacter is that it eats alcohol to make vinegar, so the yeast could do its work and then the acetobacter will take over. The acetobacter does not eat sugar, it eats beer, so they are not in direct competition. That is why you need to cover starters with foil or use airlocks.
 
Fruit FlyPA? Could be the next big style....

-ben
Oh, my freakin' head...I'm so wasted!...;)

I say it's still a possibility. That is how infections occur. My understanding of acetobacter is that it eats alcohol to make vinegar, so the yeast could do its work and then the acetobacter will take over. The acetobacter does not eat sugar, it eats beer, so they are not in direct competition. That is why you need to cover starters with foil or use airlocks.
Yup. they eat the alcohol to make malt vinegar, in this case.
 
Here's a question: with as many cells as you had, would there really have been an infection?

You can search through my post history to find the thread but years ago I broke an airlock on brew day and thought I'd be ok with tinfoil for a couple of days until I grabbed another one. On bottling day I had yellow specks all over the inside of my carboy. Thinking it was lemon bits (it was a lemon wheat beer) I started prepping my bottling day only to discover it was fruit fly larvae all over the inside of the carboy. I found 2 fruit flies floating in the beer. I've never used tin foil since.
 
I've taken to wrapping the whole thing in a garbage bag, tying it tight. Problem solved and I'm sure there's enough air in that for whatever little bit needs to get into those yeasties. Not the prettiest thing.

I should have learned my lesson since a couple of years ago I made a delicious ginger beer and I had enough bottles cleaned and sanitized for the batch lying next to the exact number of unwashed bottles for the next batch. I was drunk and filled all the unwashed bottles.

I didn't even notice the fruit flies until I opened one and it was a gusher.

I have traps full of fruit flies, clean up all spills immediately, leave no food around and they still are savage this year.
 
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