Development of a Rapid and Accurate Prediction Model for Whey Separation in Pasteurized Drinking Yogurt Caused by Long-term Ambient Storage

Long-term ambient storage of pasteurized drinking yogurt (PDY) may result in excessive whey separation. This study aimed to develop a rapid and accurate prediction method of PDY whey separation when maintained at 25 °C for 45 and 90 days. Predictive models of whey separation were created by regression analysis based on the results of physical property measurements including the 48 hour Turbiscan Stability Index (TSI). The predictive model based on TSI showed a high coefficient of determination and high suitability not only when the pectin concentration in PDY was changed but also when the manufacturing conditions of PDY were changed. In addition, this model was superior in prediction accuracy and versatility as compared to models based on other physical property measurements. The advantage of the TSI model is that it allows for more rapid, accurate and versatile evaluation of spontaneous whey separation.