Effect of Different Heat Treatments on Physicochemical and Microbial Contents of Camel Milk during Storage Period

Abstract

This study was conducted during the period from December 2015–to January 2016 at Dal Dairy Factory. To determinate the effect of different heat treatments onchemical composition and microbial contents of camel milk during storage. Four litters of fresh camel milk were purchased from farm in Sharag Elneel region. The milk samples were divided into four equal portions and heated at temperatures 72 ºc/15 sec, 75 ºc/10 min , 80 ºc/5 min and 65ºc/30 min respectively. After pasteurization the milk samples were stored at 7 ºc for different storage periods ( 0, 5, 10 , 12 , 14 ) days .The camel milk samples were examined forfat, protein, total solids, lactose, pH, free fatty acid , casein and total bacteria count during the specified storage period. The statistical analysis revealed that significant difference in all chemical parameters at (P<0.05)and storage period at (P<0.01). The pH was not affected significantly by different heat treatments and different storage period. However, the heat treatment and storage period had significant (p<0.05) effect on the total bacterial count. The study showed that higher bacterial count (2.77 log cfu/ml) was for the control heat treatment (72 °C/15 Sec) and the lower one (2.45log cfu/ml) was for the 80 °C/5 min. The high bacterial count (3.67 log cfu/ml) was at the day 14.The low bacterial count (0.73log cfu/ml) was for day zero.The protein, total solids and FFA contents were decreased in the treatment (65℃/30min) on day 14.