Is sour cream in super markets made in the traditional whey? (Ha ha, just kidding.)
The traditional method of making sour cream is easy to describe: milk is spun using a centrifuge so as to extract a heavy cream, which is 1 part cream, 9 parts milk. (Cream for butter is lighter than this). The heavy cream is then cooled to thicken it, then the temperature is increased to about 85F. A small amount (1:20) of sour cream is added to initiate fermentation and the cream is gently stirred for 2 hours, then allowed to sit for 6 hours or to taste. When it is sour, it is refrigerated. In this state it can last for 2-3 months.
Modern recipes I have seen for home cooks obviously do not follow this method, because it requires having a milk separator and raw milk. Instead these recipes mix in buttermilk with light cream, or other methods, which are not true to the original method. However, I am wondering if store-bought sour creams follows the traditional method, or do modern commercial processes use light cream also?