Abstract:

With the aim to provide valuable experimental support for the application of ultrasonic technique to the sterilization of liquid foods, the effects of ultrasonic treatment conditions, such as treatment time, ultrasonic intensity and duty cycle on total bacterial count in carrot juice were investigated by single factor and orthogonal array methods. Results showed that the optimized ultrasonic treatment for 10 min with 0.7 duty cycle and 200 W/cm2 ultrasonic intensity resulted in an optimal sterilization effect. In addition, in comparison with high temperature treatment, ultrasonic treatment could effectively reduce the loss of β- carotene in carrot juice, thereby favoring the retention of nutritional quality.

Key words: carrot juice, ultrasonic, sterilization