Improving the textural properties of an acid-coagulated (Karish) cheese using exopolysaccharide producing cultures

Exopolysaccharide (EPS)-producing Streptococcus thermophilus (CHCC 3534) or its EPS-negative genetic variant S. thermophilus (CHCC 5842) was combined with Lactobacillus delbrueckii ssp bulgaricus (CHCC 769) and used to manufacture Karish cheese to determine the effect of EPS production on the composition, sensory and textural characteristics. Moisture and yield were about 2% higher in cheese made using EPS-producing culture than that made using the EPS-negative mutant. Texture profile analysis showed that the textural characteristics (hardness, consistency, adhesivness, chewiness, relaxation and modulus) were significantly lower in cheese made using EPS-producing culture while cheese made using EPS-negative mutant was significantly lower in cohesiveness. Sensory analysis confirmed the ability of EPS-producing culture to improve Karish cheese texture, as it received higher body and texture scores after aging for 7 and 15 days.