Study on flavor compounds and flavor changes of yogurt in shelf-life

The changes of main flavor compounds of commercial yogurt in storage of 4℃ were discussed.The substances included carbonyl compounds of aldehyde and diacetyl,volatile acid,and acidity.The sensory evaluation scores of the yogurt were also investigated simultaneously.The results showed that the increase of velocity was high at first and then dropped,with the tendency of the increase of these flavor compounds.The yogurt had coordinated flavor when the ratio of aldehyde and diacetyl was 0.56~0.80.The correlation analysis of flavor compounds and sensory evaluation scores proved that the correlations of flavor compounds were significant between one another.And the compounds had influence on flavor strength and flavor coordination in varying degrees.