The effect of using an exopolysaccharide-producing culture on the physicochemical properties of low-fat and reduced-fat Kasar cheeses.

摘要

A mixed starter culture containing exopolysaccharide (EPS)-producing strains of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus was combined with Lactobacillus helveticus LH301 and used in the manufacture of low-fat and reduced-fat Kasar cheeses. For comparison, low-fat (C10) and reduced-fat (C20) cheeses were made using EPS-producing (EPS+) starter strain and EPS-non-producing (EPS-) starter strain. The physicochemical properties of the cheeses were assessed in terms of chemical composition, texture, microstructure and microbial content over 90 days. Cheeses made with EPS-producing culture (EPS10 and EPS20) had lower protein contents than control cheeses with 10% and 20% fat in dry basis (C10 and C20). Scanning electron microscopy images showed that using EPS-producing culture resulted in a less compact protein matrix and sponge-like structure in the cheese samples. In general, cheeses made using EPS-producing culture had lower total viable counts. This could be related to the reduced survivability of EPS-producing cells in the cheese matrix during ripening due to autolysis ability