Characterization of the Lactic Acid Bacteria in Anbris (Fermented Goat's Milk) and Preliminary Probiotic Selection

Introduction: Labneh Anbris is a traditional fermented cheese-like product made of goat’s milk and highly consumed in many rural areas of Lebanon. The product is fermented over six months in a traditional setting without the addition of starter cultures, but dependent entirely on the natural microbiota present in the product. This natural fermentation process results in a final product with an extended shelf life at room temperature and contains good organoleptic characteristics.

Purpose: The purpose of this study was to investigate the potential probiotic lactic acid strains that may be naturally present in the product.

Methods: Samples were collected from two different villages (Arsal and Kweikh). Lactic acid bacteria were isolated on MRS Agar and Broth for Lactobacillus, Streptococcus, Pediococcus and Leuconostoc and M17 for the more fastidious Streptococci (incubated at 30° for 48 h). The isolated strains were then subjected to several biochemical and phenotypic tests to assess probiotic characteristics, namely, temperature and salt tolerance. NH₃ production, citrate utilization, acid and bile tolerance, antibacterial activity against Staphylococcus aureus and ACE inhibitory tests. Pulsed field gel electrophoresis (PFGE) and polymerase chain reaction (PCR) were carried for isolates characterization.

Results: Results showed that six of the Gram-positive, catalase-negative, pooled isolates from Arsal and six isolates from Kweikh have potential probiotic characteristics by scoring positive to all the biochemical tests that were performed. Further molecular analyses and confirmation tests with PFGE and PCR indicated that the isolated probiotic strains are of the Leuconostoc (8 strains) and Streptococci (4 strains) genera.

Significance: The results are the first on such traditional products in Lebanon. It is highly important to identify probiotic strains in Anbaris. Anbaris is of high nutritional, health and economic value, and a commodity for isolating probiotic strains may be used in the production of new types of dairy-based functional foods.