Comparison of composition, sensory properties and aroma compounds of kefir produced from donkey milk and cow milk

In this study, donkey milk and cow milk used for kefir production and the kefir samples were characterised based on compositional and microbiological properties, volatile aroma compounds, amino acid composition, and sensory analyses during storage for 21 days at 5 degrees C. Compared to cow milk kefir (CMK), donkey milk kefir (DMK) had lower contents of total solids, fat, and protein. Using donkey milk resulted in a weaker body characteristic in the kefir sample due to its low total solids content and the low ratio of casein. Acetaldehyde and acetic acid formation were at a remarkable level in DMK. Besides, the high lactose content of donkey milk caused more ethanol production in the kefir. Tyrosine, valine, and arginine were the primary amino acids in DMK. Donkey milk kefir was evaluated as acceptable in the aspect of sensorial properties such as taste and odour. Based on the present results, it could be concluded that a probiotic fermented beverage can be produced from donkey milk.