*Nature's Goodness Kefir Turkish Yoghurt Probiotic*: Kefir is a fermented milk drink that originated in the Caucasian Mountains near Turkey, where it was used for centuries as a healthy drink. How Kefir works: Kefir is a probiotic - a source of beneficial bacteria and yeasts which help maintain a healthy digestive system. These include Lactobacillus, Lactococcus, Leuconostoc, and Saccharomyces kefir. 5 sachets make 25L. Benefits: Kefir has been found to help maintain healthy intestinal flora.