Body Improvement of Bio Kareish Cheese by Using Exopolysaccharides- Producing Bacterial Strains

The aim of this study was to investigate the body improvement of exopolysaccharide (EPS)-producing lactic acid bacteria (LAB) when used in making bio Kareish cheese. Chemical, bacteriological, textural, electron microcopical and organoleptic characteristics of the examined cheese was studied during storage period at 5±1°С for 21 days.Six treatments of Kareish cheese were made by YC-XII (containing of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus) (T1), ABT-2 (containing of Lb. acidophilus, Bifidobacterium bifidum and Str. thermophilus) (T2), EPS (containing of Streptococcus thermophilus TH-4^TM, MR-1C and Lactobacillus delbrueckii subsp. bulgaricus 12DRI/VAC, MR-1R) (T6). In addition of using the previously mentioned starters T1 with T2 (T3), starters T1 with T6 (T4) and starters T2 with T6 (T5), for cheese making. Significant differences (p≤0.05) were found between cheese treatments as affected by the type of bacterial starter, and the way used in milk coagulation. Results indicated also that the addition of EPS with ABT-2 to Kareish cheese increased the yield, total solids, titratable acidity and the content of protein in dry matter. The textural characteristics revealed that the hardness and gumminess negatively correlated to cohesiveness and springiness. Kareish cheese made with starter EPS with ABT-2 (T5) was of the lowest hardness, but was of the highest springingess, gumminess, cohesiveness and chewiness. Coliform bacteria were not detected in any samples. The Kareish cheese samples of starter EPS with ABT-2 (T5) or EPS (T6) were found to be of good microstructure, compared to control samples. Organoleptic characteristics showed that Kareish cheese made with EPS producing ABT-2(T5) starter were more accepted by the panelists.