Milk containing alcohol can prevent food allergies in babies. Scientists say that ingredients in the fermented drink kefir may block immune responses which cause allergic reactions.

It is already used to wean babies in eastern Europe — and is believed to help Bulgarian peasants live longer.

Boffins in Taiwan tested the drink on mice.

After three weeks, the amount of Ovalbumin – a protein found in egg whites which causes most allergic reactions in tots – reduced threefold.

The study also found that the drink raised levels of “friendly” bacteria.

Dr Ji-Ruei Liu, writing in the Journal of the Science of Food and Agriculture, said: “Maybe we can screen out certain components from kefir and utilise them in medicine.”

But allergy specialist Sharon Matthews, said: “We need much more supportive evidence before a human trial could be contemplated.”