A novel approach of direct formulation of defined starter cultures for different kefir-like beverage production

Six pure microbial strains, Kluyveromyces marxianus BD01004, Lactobacillus delbruekii ssp. bulgaricus BD00014, Lactobacillus kefiri BD00002, Streptococcus thermophilus BD00089, Lactococcus lactis BD00736 and Leuconostoc mesenteroides BD01701, previously isolated in our laboratory from diverse sources, were combined in different proportions for the formulation of defined starter cultures for the production of kefir-like beverages in 10% (w/w) reconstituted skim milk. The physicochemical properties of products obtained were analysed by high performance liquid chromatography for ethanol, lactose and lactic acid contents, and by gas chromatography–mass spectrometry for determination of volatile compounds. A comparative study of these products with kefir was further undertaken with the purpose of determining suitable starter culture combinations for production of kefir-like beverages. The results indicated that some of the starter cultures devised were consistent with the production of beverages with characteristics approximating to those of traditional kefir as reported in the literature.