Abstract
Camel and cow milks were used for production of sweet and acid whey and lactic acid. Sweet camel whey (SMW), sweet cow whey (SOW) and acid camel whey (AMW) had the highest percentage of protein, lactose, and ash. Acid cow whey (AOW) had the highest moisture content. Lactobacillus delbrueckii ssp. bulgaricus CH2 was used for the fermentation of whey samples to produce lactic acid. At the end of fermentation time (28h) SMW, SOW, and AMW had similar concentrations of lactic acid (14.22, 13.58, and 14.08 g/l, respectively). SOW had the highest productivity (0.36 g/l/h), lactose conversion (57.3%), and yield (0.21) compared to the other samples. Lactose concentration decreased with time and AOW had the lowest lactose utilization (22.7%). The pH of whey samples decreased with increasing fermentation time until 12h, then it remained constant. On the other hand, titratable acidity increased with increasing fermentation time and both SMW and AMW had the highest acidity (1.31% and 1.30%, respectively) compared to the other two samples.