It's a drink derived from milk fermentation.
The secret of yogurt are lactic ferments or better speaking "friend"
bacteria:
Streptococcus thermophilus, Lactobacillus bulgaricus and others.
Yogurt can be eaten as is, mixed with fruits, suitened with honey
or used as ingredient for other dishes.
Somebody uses it to replenish the bacterial flora in the digestive tract or simply to aid digestion.
It helps keep high the immune difences.
Yogurt keeps better than milk, that's why it is so popular in countries
with warm climates.
Some populations use it since ancient times: yogurt can be considered the precursor of cheese.
A Persian tradition says that (the biblical) Abraham owned his virility and longevity to yogurt.
The name probably comes from the turkish yoğurmak (melt).
The first documented references are from Turkish documents written in 11th century.
The first scientist to study it in a lab was the russian Ilya Ilyich Mechnikov.
He noted the longevity of bulgaric populations that where using yogurt.
He convinced an entrepreneur, Isaac Carasso, to start industrial yogurt production.
In 1919 in Barcellona has born the first industrial settlement, the company
was named Danone (little Daniel, his son).
Set Yogurt
Stirred Yogurt
NOTE: lactic ferments transform lactose in lactic acid.
The acid acts as rennet letting milk agglomerate.
Basically there are 2 different kind of yogurts: set where fermentation occurs directly in the final cup stirred where fermentation occurs in a specific can and at end the result
is melted (curd is broken) and the result then poured in final cup.
The main difference is that the first is decisely dense, like a pudding,
and the second one is a cream.
The yougurt you can normally buy is the stirred one.
Some artigianal set yogurts have a non uniform density and many clots but they
hae a limited market: density and cloths give the idea that yougurt has go bad,
but, usually, it is of superb quality.
Artisan Made Set Yogurt
The set yougurt ferments are lightly different, and if you try to reproduce
them maybe you will not succeed:
one must respect the original conditions of temperature and kind of milk.
For instance with some kind of artigianal yougurts, derived from raw milk from bio breeding and using ferments
not used to sugar and other additives, you will not succeed reproducing yogurt
if using supermarket milk.
To get more information about yogurt see for instance DairyAustralia.com Here a recipe to make yogurt at home.
Fonte: wikipedia
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