The word yoghurt is derived from the Turkish word ‘yoghurmak', which means ‘to thicken'. Yoghurt is a fermented dairy product. It's made from milk to which the starter cultures (fermentation bacteria) Lactobacillus debrueckii ssp bulgaricus and Streptococcus salvarius ssp thermophilus are added to convert lactose (milk sugar) into lactic acid. This transformation thickens the milk and gives it its typical sour taste. The final product may be called ‘yoghurt' only when the mentioned bacteria are used and present in high numbers.
Although the consistency, flavour and aroma may vary from one region to another, yoghurt is consumed world-wide. It is mostly used for desserts, breakfast or side dishes.