yoghurt, or yogurt or yoghourt. Food made
from milk fermented with bacteria, often with
fruit or other flavourings added.
Heat-treated, homogenized milk is inoculated
with a culture of Streptococcus thermophilus
and Lactobacillus bulgaricus in equal
amounts, which change the lactose in the milk
to lactic acid. Acetaldehyde gives yoghurt
its characteristic flavour. Commercially,
fruit, flavourings, and colouring and
thickening agents are added to the fermented
yoghurt.