Despite their salubrious sounding name, fruit flies (Drosophila species),
eat food that is decaying. They inhabit rubbish bins, compost heaps or any place where food is present, including drains. Rotting food is rich in germs, any of which a fly can pick up on their body and transfer to where it next lands.
These bacteria include E coli, Listeria, Shigella, and Salmonella, any of which can cause a potentially serious infection in even healthy people. The fruit fly, you realise, may have just deposited potentially lethal microbes in your wine, so you toss it in the sink and pour a fresh glass.
Alcohol is well known to be inhibitory to germs and is one reason wine can be stored for so long. Several laboratory studies have also shown that the combined effects of wine alcohol and organic acids, such as malic acid, can prevent the growth of E coli and Salmonella.
FoodWorld 