Kefir shall contain not less than 3.5 percent milk fat. Reduced-fat kefir shall contain not more than 2.1 percent milk fat. Lowfat kefir shall contain not more than 1.2 percent milk fat. Nonfat, skim, or fat-free kefir shall contain a maximum of twenty hundredths of 1 percent milk fat.
Kefir made from goat milk shall contain not less than 2.8 percent of milk fat.
Ca. Food and Agric. Code § 38872