Effect of Ultrasound Treatments in Papaya Juice Processing

The influence of ultrasound (time and temperature) and conventional heating (temperature and time) under different processing conditions on the quality attributes and microbial inactivation potential of papaya juice was investigated. Sonication is seen to be useful for minimal processing, due to the fact that transferring of acoustic energy to food is instantaneous and throughout the whole product. The lethal effect of ultrasound is reported to be very much dependent on type of microorganism and processing parameters and medium. In the present work, the effect of sonication, coupled with conventional heating on quality of papaya juice was studied. Experiment was conducted varying the ultrasound time and temperature and the results are compared with the conventional heating. The effects of sonication and temperature on the quality of papaya juice were studied for selected physicochemical properties such as pH, acidity, total soluble solids, ascorbic acid content and microbial stability. Ascorbic acid content was found to be significantly higher in samples treated with sonication at 50 degrees C for 20 min than in the control. Sonication alone was not very effective in sterilizing the papaya juice, it needs to be combined with high temperature for the sterilization of papaya juice.