Comparison of buffalo's, sheep's and goat's yoghurts in terms of their antioxidant activity, angiotensin-converting enzyme (ACE) inhibitory activity, volatile compound content and 5-hydroxymethylfurfural (HMF) content

This study examined yoghurt samples produced using classical yoghurt culture from buffalo's, goat's and sheep's milks in terms of their physicochemical characteristics, DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity, angiotensin-converting enzyme (ACE) inhibitory activity, and contents of total phenolic compounds (TPC), volatile compounds and 5-hydroxymethylfurfural (HMF). It was determined that the use of different types of milk in yoghurt production had a statistically very significant effect (p < 0.01) on all physicochemical and biochemical properties analyzed, whereas the storage period had a very significant effect (p < 0.01) on pH and titratable acidity. Compared to other types of milk, sheep's milk was found to be superior in terms of antioxidant activity and ACE inhibitory activity, whereas buffalo's milk was found to be superior in its content of volatile compounds. The highest HMF formation was observed in yoghurt samples produced from goat's milk. It is therefore suggested that the consumption of yoghurts produced from different types of milk should be expanded because of their nutritional value and bioactivity.