Lactic Acid Bacteria Viability and Sensory Evaluation of Yogurt Prepared From Different Breeds Goat Milk

Abstract

This study was conducted on six breeds of dairy goats (Nubian, cross Nubian and Saidi, Aradi, Shami, Sheraky) in an attempt to explore the in-breeding differences which are reflected in the milk produced from each breed. The gross components of the six breeds milk were analyzed and the yogurt was prepared from each. The viability of two strains of starters (Lactobacillus bulgaricus and Streptococcus thermophilus) were used in manufacturing of the yogurt was measured, as well as the sensory and rheological properties of the produced yogurt. The results reflected that the fat and TS percentages were higher in 2 breeds goat milk (Nubian and Shami) than the other breeds, by 4.47, 06.97% for fat and 11.86, 18.48 % for TS respectively. The viability of Lactobacillus (L.) bulgaricus in yogurt at day 12 of storage was the highest in the yogurt of Nubian and Shami goat milk 1.9x 107 and 2.1 x 107 CFU/g respectively, while, the strain Streptococcus thermophilus showed the viability rate at day 12 of 5.0 x 108 and 505 x 109 CFU/g in Cross Nubian and Shami yogurt respectively. The sensory evaluation and over all acceptability were high in yogurt of Cross Nubian and Nubian and Shami breeds respectively, the study observed a strong connection between TS percentage and yogurt production, but the acceptability of yogurt was varying across breeds. More studies should be applied to declare the differences and produce a suitable yogurt acceptable to consumers to get complete benefits from goat breeding.