It's not really true what thecarp
wrote. The main bacteria
used are Lactobacillus bulgaricus
and Streptococcus thermophilus
, but the culture
cocktail also contains more strain
s of lactobacilli
, as well as Bifidobacterium
strains. The different types of yoghurt
are produced by different mixtures, and ratio
s of the involved bacteria
, as well as the type of milk
used (the animal, low/high fat content).
is fermented to lactic acid
s are formed (that's the component that makes the yoghurt slimy and lumpy).
(the reasons for the high temperature during the industrial production process is, that they want to have full control over the bacteria in the milk, and has to have a longer shelf life than your home-made yoghurt.)
in your kitchen can be done more easily:
just warm the milk to body temperature, add yoghurt (2-3 teaspoons per litre) and pour it into a clean jar
, close it, wrap a towel around it and leave it next to the radiator
for 3-8 hours. This even works to make soy
Thing is, you can't keep on doing this. After two or three times using you home-made yoghurt as inoculant
, the ratio
of bacteria has changed, because some of them grow faster than others, hence the taste will be different.