Fermented Milk Products from All Over the World. Kærnemælk (Denmark)
Kærnemælk is actually the traditional buttermilk prepared in Denmark and other countries in northern Europe. The milk is fermented into a cream, and then sour cream, which can be further turned into butter and buttermilk. To make sour cream out of cream, a DL starter culture is used. A DL culture means that there are several types of bacteria used for the fermentation process, DL meaning that Streptococcus lactis, Streptococcus cremoris, Streptococcus diacetylactis and Leuconostoc citrovorum will be used for the fermentation process that will turn cream into sour cream. Streptococcus lactis, Streptococcus cremoris, Streptococcus diacetylactis are used to trigger acidity in the fermented milk product, while Leuconostoc citrovorum is used for flavor and aroma. The ideal temperature for the fermentation process is between 20 and 22 degree Celsius. It is rather low than in comparison with other fermentation processes involving milk, but the temperature must be maintained in the mentioned range because if not, the lactococci will multiply too much and will take over the leuconostoc cultures, completely changing the taste and flavor of the product. Buttermilk is known for its sweetness, so preparing it at higher temperatures will give it a yogurt-like taste, instead of keeping it sweet.