الفهرس | Only 14 pages are availabe for public view |
Abstract This study was performed to investigate the chemical and microbiological quality of some traditionally produced dairy products (Ras, Domiati, Karish cheeses and Mish) 200 random samples (50 each) were examined. The mean values of moisture, salt and acidity % for Ras cheese were (30.3, 3.30 and 0.65), respectively, while (56.44, 6.63 and 0.68) for Domiati cheese, (77, 0.95 and 0.63) for Karish cheese and (85.70, 7.56, 0.50) for Mish samples, respectively. Mean counts of total bacteria, presumptive coliform, staphylococci, yeast and mold were (2×108, 3×105, 1×106, 3×105 and 7×103) for Ras cheese, (3×106 5×10, 4×105, 1×105 and 4×103) for Domiati cheese, (9×106, 5×10, 3×103, 8×105 and 7×102) for Karish cheese and (1×107, 5×102, 1×105, 5×105 and 3×104) for Mish samples, respectively. There was a significant correlation coefficient between chemical parameters and the examined microorganisms. Some potentially pathogenic microorganisms were isolated as Escherichia coli that serologically identified as O125, O18 and O114, as well as the virulence genes fimH and iss were detected by molecular examination. Enterotoxigenic Staphylococcus aureus strains producing enterotoxin (B, D and E) were also detected. Therefore, strict hygienic measures should be applied during manufacture, handing and distribution of traditional products. On the other side of the study, synbiotic Karish cheese was produced as a trial for improving such cheese type. Using Lactobacillus plantarum and inulin (4%) positively improved sensory characteristics, hygienic quality and shelf life of Karish cheese. In addition, L. plantarum showed a great inhibition against Enterobacter aerogens. Moreover, using of 4% inulin significantly increased the survival of L. plantarum throughout the entire storage period. |