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Abstract Fifty sample of freshly drawn evening cow’s and buffalo’s milk were obtained from three village distribute in Assiut City (El-wasta, banimor and khalaf Rashed). Samples were collected in a sterile glass stoppered bottles, kept in insulated ice box, transferred to laboratory without delay. At laboratory each sample is divided into 2 main portions each (250 ml) and stored at ambient temperature, one of them kept as control while, the other as activated sample. Activation of lactoperoxidase (LPS) with KSCN and Na2Co3 : 3H2O2 through 2 hrs from milking. A concentration of 10 ppm KSCN: 10 ppm H2O2 to determine the effect of activated LPS on keeping quality of raw milk. a- Sensory evaluation of milk: The mean of sensory evaluation of examined control cow’s milk samples after 0, 12, 15, 18, 21, 24, 27 hrs were 8, 6, 5, 5, 4, 3, 2, respectively while in activated samples after 0, 12, 15, 18, 21, 24, 27, 30, 33 hrs were 8, 7, 6, 5, 4, 3, 2, 2, 1, respectively. The mean of sensory evaluation of examined control buffalo’s milk samples after 0, 12, 15, 18, 21, 24, 27 hrs were 8, 7, 6, 5, 3, 2, 2, respectively. In activated samples at 0, 12, 15, 18, 21, 24, 27, 30, 33, 36 hrs were 8, 7, 6, 6, 5, 4, 3, 2, 2, 1, respectively. 2-Sanitary evaluation of milk A-COB (clot on boiling) In cow’s milk, the control spoiled at 30 hrs earlier than treated samples which spoiled at 39 hrs and the accepted samples in treated higher than control after 21 hrs. In buffalo’s milk, the control spoiled at 33 hrs earlier than treated samples which spoiled at 39 hrs and the accepted samples in treated higher than control after 21 hrs. B- APT (Alcohol precipitation test) In cow’s milk, the control spoiled at 30 hrs earlier than treated samples which spoiled at 36 hrs and the accepted samples in treated higher than control after 21 hrs. In buffalo’s milk, the control spoiled at 33 hrs earlier than treated samples which spoiled at 36 hrs and the accepted samples in treated higher than control after 21 hrs. 3- Bacteriological evaluation of milk A-Total bacterial counts The mean of total bacterial count of the examined control raw cow’s milk samples after 0, 12, 15, 18, 21, 24, 27 hrs were 6.5x105, 4x106, 4.8x106, 4.9x106, 4.3x106, 5.1x106, 4.5x106 cfu/g respectively. While in activated samples after 0, 12, 15, 18, 21, 24, 27, 30, 33, 36 hrs the mean count were 6.5x105, 3x106, 4x106, 4.1x106, 4.3 x106, 4.4x106, 4.4x106, 4.7x106, 4x106, 5.6x106 cfu/g respectively. The mean of total bacterial counts of the examined control raw buffalo’s milk samples after 0, 12, 15, 18, 21, 24, 27, 30 hrs were 1.2x105, 1.9x106, 2.6x106, 2.6x106, 2.7x106, 3.2x106 and 4x106, 4.8x106 cfu/g respectively. While in activated sample after 0, 12, 15, 18, 21, 24, 27, 30, 33, 36 hrs the mean were 1.2x105, 1.6x106, 1.9x106, 2.4x106, 2.2x106, 2.8x106, 3.4x106, 3.5x106, 3.5 x106, 4.8x 106 cfu/g, respectively. Coliforms and fecal coliforms and E. coli count (MPN): The mean of coliforms counts of the examined control raw cow’s milk samples after 0, 12, 15, 18, 21, 24, 27 hrs were 3.5x10, 2.96x102, 2.53x102, 4.43x102, 6.39x102, 8.72x102, 7.20 x102 cfu/g respectively. While in activated sample after 0, 12, 15, 18, 21, 24, 27, 30, 33, 36 hrs the means were 3.5x10, 2.78x102, 2.36x102, 2.62x102, 3.76x102, 5.62x102, 7.42x102, 8.62x102, 8x102 cfu/g respectively. Fecal coliforms counts of the examined raw cow’s milk samples: In control samples after 0, 12, 15, 18, 21, 24, 27 hrs the means count were 1x10, 0.7x10, 1x10, 1.8x10, 1.1x10, 0.1x10, 1.1x10 cfu/g, respectively. While in activated sample after 0, 12, 15, 18, 21, 24, 27, 30, 33, 36 hrs the mean were 1x10, 1.53x102, 3.5x10, 6x10, 1x10, 0.1x10, 0.1x10, 0.1x10, 0.1x10, 0.1x10 cfu/g, respectively. E. coli counts of the examined raw cow’s milk samples: In control samples at 0, 12, 15, 18, 21, 24, 27 hrs the mean count were 0.1x10, 0.5x10, 1x10, 1.8x10, 1.1x10, 0.1x10, 1.1x10/ml respectively. While in activated sample at 0, 12, 15, 18, 21, 24, 27, 30, 33, 36 hrs they were 1.57x102, 3.3x10, 1x10, 1x10, 0.1x10, 0.1x10, 0.1x10, 0.1x10, 0.1x10 cfu/g,respectively. Coliforms counts of the examined raw buffalo’s milk samples: In control samples at 0, 12, 15, 18, 21, 24, 27 hrs the mean count were 2x10, 3.76x102, 4.80x102, 4.37x102, 3.89x102, 1.49x102 and 4.41x102 cfu/g, respectively. While in activated sample at 0, 12, 15, 18, 21, 24, 27, 30, 33, 36 hrs they were 2x10, 3.82x102, 4.80x102, 4.04x102, 2.99x102, 2.58x102, 7.19 x102, 6.66x102, 6.57x102 and 9x102 cfu/g, respectively. Fecal coliforms counts of the examined raw buffalo’s milk samples: In control samples at 0, 12, 15, 18, 21, 24, 27, 30 hrs the mean counts were 0.1x10, 2.2x10, 5.2x10, 5.8x10, 6.6x10, 0.1x10, 0.1x10, 0.1x10 cfu/g respectively. While in activated samples at 0, 12, 15, 18, 21, 24, 27, 30, 33, 36 hrs they were 0.1x10, 5.6x10, 0.3x10, 2.9x10, 1.7x10, 0.4x10, 0.6x10, 0.1x10, 0.1x10, 0.1x10 cfu/g respectively. E. coli counts of the examined raw buffalo’s milk samples: In control samples at 0, 12, 15, 18, 21, 24, 27, 30 hrs the mean were 0.1x10, 2.2x10, 5.2x10, 5.8x10, 6.6x10, 0.1x10, 0.1x10, 0.1x10 cfu/g respectively. While in activated sample at 0, 12, 15, 18, 21, 24, 27, 30, 33, 36 hrs they were 0.1x10, 5.6x10, 0.3x10, 2.9x10, 1.7x10, 0.4x10, 0.6x10, 0.1x10, 0.1x10, 0.1x10 cfu/g, respectively. The average extension in shelf life of treated milk under ambient temperature was 5.52 hrs in cow’s milk and was 5.88 hrs in buffalo’s |