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Abstract A total of 160 milk samples were collected randomly from different sources including dairy farms, farmers’ houses, dairy shops and street vendors (40 samples each) in Qena province. These samples were physically, chemically, sanitary and microbiologically examined in order to determine their quality and sanitary condition. The results obtained were summarized as follow: 1- Physical and chemical examinations. A - Specific gravity. The results of specific gravity of the examined raw milk samples recorded mean values in the following Table. Source Dairy farms Farmers’ houses Shop keepers Street vendors Specific gravity 1.029 ±0.0005 1.030 ±0.0006 1.032 ±0.0005 1.028 ±0.0005 B- Determination of chemical composition. The mean values of fat%, TS%, SNF% and water % of the examined milk samples collected from different sources are recorded in the following Table. Source Fat% 18% SNF% WaterO.Io Dairy farms 3.74 ± 0.10 12.3±0.16 8.61 ± 0.09 87.7±0.16 Farmers’ houses 4.14±0.14 13.1 ± 0.30 8.92 ± 0.23 86.9 ± 0.31 Shop• keepers 5.04 ± 0.20 14.1 ± 0.32 9.17 ± 0.16 85.8 ± 0.29 Street vendors 3.91 ± 0.14 13.0 ± 0.28 9.22 ± 0.21 86.9 ± 0.28 - Detection of inhibitory substances and preservatives. General test (Wynther Blyth test). The results of general test indicated that 9 (22.5%), 13 (32.50/0) 12 (30%) of examined farmers’ houses, shop keepers and street endors milk samples were positive for inhibitory substances and reservatives, respectively, whereas all of the examined dairy farm milk pIes were found to be negative . - Specific tests for detection of preservatives. The results indicated that all samples of the examined raw milk were free from adulteration by formalin and salicylic acid. Two samples (5%) of Farmers’ house milk were positive for boric acid while, 4 (10 %) and 1 (2.5%) of Farmers’ house and street vendors milk samples were positive for hydrogen peroxide, respectively, whereas shop keepers and dairy farms milk samples were free from hydrogen peroxide. D- Sanitary and quality tests. 1- Determination of titratable acidity percentage. Acidity percentages of different raw milk sample sources were summarized as a mean value in the following Table. Source Dairy farms Fanners’ houses Shopkeepers Street vendors . Acidity % 0.09 ± 0.006 0.15 ± 0.010 0.13 ± 0.008 0.10 ± 0.010 2- Resazurin test. Resazurin test of different sources was summarized III the following Dairy farms Farmers ’houses Shop keepers Street vendors No. % No. % No. % No. % Excellent 22 55 4 10 1 2.5 0 0 Very good 13 32.5 31 77.5 13 32.5 9 22.5 Good 5 12.5 5 12.5 18 45 17 42.5 Fair 0 0 0 0 5 12.5 11 27.5 Bad 0 0 0 0 3 7.5 3 7.5 11- Microbiological examination. Microbiological examination of raw milk samples for Aerobic Plate, Psychrotrophic, Thermoduric, Coliform, Fecal Coliform, Enterococci, and Yeast and Mold count/m I collected from different sources were summarized as a mean value in the following Table. Source APC/ ml 1.3xl06 ±1.6 xlOs 2.6xl06 ±2.8xlOs 3.6xl07 ±1.0xl07 3.8xl07 ±5.9xl06 Dairy farms Shopkeepers Psych/ ml 2.4xl04 ±2.lxl03 1.6xlOs ±2.8xl04 Therm/ MI 4.8xl03 ±8.2xlOz 4.5xl03 ±4.5xlOz Col /ml 9.3xl04 ±2.9xl04 2.8xlOs ±4.lxl04 1.6xlOs 8.9xl03 2.3xlOs ±2.5xl04 ±1.7xl03 ±6.lxl04 1.0xl06 1.3 xl 04 3.8xlOs ±3.5xlOs ± 1.4xl 04 ±1.6xlOS F.coV 0.97xlOI ±2.6 2.6xlOI ±4.0 8.5xlOI ±38.3 1.7xlOz ±45.1 Entero/ ml 7.lxlOz ±1.6xlOz 1.2xl03 ±1.6xlOz 4.3xl03 ±4.7xlOz Y&MI ml 6.7xl03 ±6.7xlOz 1.8xl04 ±3.8xl03 7.lxl03 ±9.0xlOz 1.6xl04 1.7xl04 ±7.8xl03 ±2.2xlOJ The hygienic measures recommended for production of high quality raw ilk and to improve its keeping quality were discussed. |