starter culture for kefir production – contain a complex microbial symbiotic mixture of lactic acid bacteria (LAB) (Lactobacillus, Lactococcus, Leuconostoc, and Streptococcus spp.), acetic acid bacteria (Acetobacter) and yeasts (Kluyveromyces, Saccharomyces and Torula) included in a polysaccharide–protein matrix ( Farnworth, 2005).