fruit flies, HELP!!!

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Aug 2, 2009
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Ok, how worried should I be. I have tried to be very careful but these flies are awful. I have a trap out and am catching them but they are still in my house. Last night I was working on some grapes, smashing and juicing and working with a fan on trying to keep flies away. Put juice in primary covered with a towel and sheet after adding campden tabs. This morning checking temp and sg. and notice a fruit fly floating in must! Am I in trouble? Please any advice? thanks
Ahh Protien!. Don't worry not a big thing I've had jellow jackets making it their swimming pool. If it really bothers you go and get some ribbon fly paper and hang above the bucket.
I always kid my sister about whether or not she washed the bird doo off :)lol. It all just adds to the flavor.:b

make some fruit fly traps by filling a wine bottle with a small bit of wine and a drop of soap in it like this:

Do not worry too much.
For your wine to become vinegar it needs oxygen and no sulphite.
I bet your wine is fermenting vigorously and so provides a layer of CO2 which keeps the oxygen out.
And you will off course have protected the must with campden tablets (sulphite).
If this is so you generally will be fine.

Luc, I did put campden tabs in and am waiting for the 24 hrs to put in the yeast. I also made a trap by puting some cut up apples with a little wine in a bowl with plastic wrap on top. I then punched small holes in the top and it is working well to trap the flies but there are a few still flying around the house. I won't stress about the thing in the must since everyone thinks it's ok. It's just that with all the caution about the fruit flies and being very meticulous about cleanliness I thought maybe that would ruin the whole batch:) thanks for the info. Laurie
You should get some kind of string or elastic band to keep the towel tight so the bugs cant get in there. These fruit flies do carry the acetobacter but like Luc said the sulfite level has to be very low for that to turn into vinegar and just another reason why people who make wine without these chemicals are playing Russian Roulette.
I get sick of the flies, they are attracted to C02. exactly what is being produced during fermentaion 'Be glad it fruit flys and not mosquitoes they are also attracted to C02.
I've used the dutchmans fruitfly trap idea with good success. Just emptied out a wine bottle that had about 9 or 10 flies lying on the bottom.. started up a new bottle today and there's one already there.

For the Canadians in the forums you can see the same principle being employed by Tim Hortons, at least in southern ontario... many of the franchises have these big pots filled with a funny looking yellow juice hanging from the garbage pails near the drive through windows.... take a close look and you'll see all the dead flies in them. It's very effective.