Microbiological Changes and Determination of Some Chemical Characteristics for Local Yemeni Cheese

The changes in microbiological parameters during the storage of local Yemeni cheese were studied. Both the smoked and the non smoked cheese were produced by using traditional techniques in some regions of Yemen. Microbiological examination was carried out at 2, 4 and 7 days of storage for serve cheese and compared with control cheese prepared in laboratory. During storage period, the total viable bacteria count, lactic acid bacteria, staphylococci, coliforms, yeast and molds increased and reached to 11.97, 10.36, 11.8, 13.4, 11.8 and 8.9 Log cfu/g, respectively, in some samples and then decreased at the end of storage period. Also, the number of coliforms, staphylococci, yeast and molds in cheese samples were higher than limits allowed by the national standards for Yemeni soft cheese. Pathogenic flora as Salmonella and Listeria were detected in some samples and disappeared at the end of storage period. . The hygienic quality of smoked cheese was best than non smoked cheese. At the final days of storage a sharp drop in pH values changing from 5.4 to 4.1 was noticed. The average contents of chemical composition of smoked and non-smoked cheeses were that, moisture 46.55 and 57.27%, fat 21.29 and 20.67 %, protein 14.87 and 16.98% salt 5.01 and 3.75 % respectively.