100% certified organic whole milk with no added water or salt or anything other than probiotic kefir culture. The kefir then goes through very slow fermentation for at least 12 hours. The bacteria you will positively find inside are:
Lactobacillus kefir
Lactococcus lactis subsp. lactis
Lactococcus lactis subsp. lactis biovar diacetylactis
Lactococcus lactis subsp. cremoris
Lactobacillus bulgaricus
Streptococcus thermophilus