Fruit Flies

I have red wiggler worms inside the porch. Normally they are outside, but they die if they freeze. My plan was to feed them to the chickens in the dead of winter for protein supplementing. I also had a whole bunch of tomatoes that I picked green because frost came so early. Well, it seems between the worm farm, which does get vegetable and fruit scraps, and the tomatoes, the fruit flies have bred. They are everywhere in the house. I have done the obvious...removed the tomatoes and any undigested matter in the worm bin, but the flies persist. They are even in the fridge and freezer, albeit dead after a short while in the freezer. (It does amaze me as to how long they can live in such cold). Do you know of a foolproof way to rid the house of these nasties?

I will try the vinegar trap for sure. I bought the yellow stickies..no avail. I bought white stickies too, but the fruit flies are not attracted to them.I think the vinegar might do the trick. Thank you.

They really like apple cider vinegar. I have noticed that if I keep a thick layer of dry bedding on my worm bins and limit the high acid waste that goes in the bins, the fruit flies don't get into my worm bins. Fruit flies seem to always come in with my tomatoes though.