Addition of buttermilk powder improved the rheological and storage properties of low-fat yogurt

Buttermilk is used widely in dairy products due to its good emulsifying and nutritional properties. In the present study, 0%-4.0% (w/w) buttermilk powder was added to low-fat yogurt with a constant protein content to investigate its efficacy on the rheological and storage properties of low-fat yogurt. Buttermilk increased the final titration acidity. Addition of buttermilk decreased the pH at the gelation point, shortened the gelation time, and thus shortened the fermentation period. Storage modulus G', yield stress, yield strain, and compact cross-links of the microstructure were enhanced greatly with addition of 1.0%-2.0% (w/w) buttermilk powder. In addition, addition of buttermilk decreased whey separation and increased the viscosity and firmness of low-fat yogurt during storage. Our findings suggest that the addition of an appropriate amount of buttermilk altered the rheological characteristics and improved the textural and storage properties of low-fat yogurt.