Sour cream is a sour milk product made from cream and sourdough. The degree of fat content varies from 10 to 58%.
Sour cream represents a
cream, subjected to lactic acid fermentation.
In the past, before the invention of the separator, sour cream was obtained quite simply: the upper, settled layer was removed from sour milk ("swept") and kept in a cool place.
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Nowadays, in the industrial production of sour cream, milk is first separated, that is, separated into cream and skimmed milk. Next, the cream undergoes normalization — this process ensures the necessary fat content of the cream.
To eliminate pathogenic microflora, normalized cream is pasteurized (heated in pasteurizers). Next, the cream enters the containers in which the leaven is added.
Cream is fermented with mesophilic and/or thermophilic streptococci. After the cream acquires the necessary acidity, it is cooled to approximately 8 °C and left for ripening, which lasts for about a day, after which the cream turns into sour cream, which becomes thick and acquires its characteristic, specific taste.