Crème frche 0.2–0.8% Sour cream 0.8% Ropy milks 0.8% Koumiss 0.5–1% Kefir 1% Product Characteristics Yogurt Tart, semisolid, smooth; green aroma Tart, thickened liquid; buttery Buttermilk aroma Crème Mildly tart and thickened; frche buttery aroma Sour Mildly tart, semisolid; buttery cream aroma Ropy Mildly tart, semisolid, slimy; milks buttery aroma Mildly tart, thickened liquid; Koumiss effervescent, 0.7–2.5% alcohol Tart, thickened liquid; effervescent, Kefir 0.1% alcohol Sour cream, crème frche, and buttermilk are indigenous to relatively cool western and northern Europe, where milk spoils more slowly and was often left overnight to separate into cream for buttermaking The lactococci and Leuconostoc species that produce them are “mesophilic,” or moderatetemperature lovers that probably first got into milk from particles of pasturage on the cows’ udders They prefer temperatures around 85ºF/30ºC but will work well below that range, and develop moderate levels of lactic acid during a slow fermentation lasting 12 to 24 hours Yogurt Yogurt is the Turkish word for milk that has been fermented into a tart, semisolid mass; it comes from a root meaning “thick.” ... lactococci and Leuconostoc species that produce them are “mesophilic,” or moderatetemperature lovers that probably first got into milk from particles of pasturage on the cows’ udders They prefer... Sour cream, crème frche, and buttermilk are indigenous to relatively cool western and northern Europe, where milk spoils more slowly and was often left overnight to separate into cream for buttermaking The lactococci... 85ºF/30ºC but will work well below that range, and develop moderate levels of lactic acid during a slow fermentation lasting 12 to 24 hours Yogurt Yogurt is the Turkish word for milk that has been fermented into a tart, semisolid mass; it