Design, development and evaluation of an automatic fruit-juice pasteurization system using microwave - ultrasonic...

Area of Science:

• Food Science and Technology
• Agricultural Engineering
• Biotechnology

Background:

• Conventional pasteurization significantly degrades fruit juice quality, impacting nutritional and sensory attributes.
• There is a need for advanced preservation techniques to maintain the quality of fruit juices like sour cherry juice.

Purpose of the Study:

• To compare the efficacy of combined microwave and ultrasonic treatments against conventional thermal pasteurization for sour cherry juice.
• To evaluate the impact of these treatments on key qualitative characteristics, including vitamin C, phenolics, and anthocyanins.

Main Methods:

• Development of an automated system integrating microwave and ultrasonic technologies for juice treatment.
• Optimization of ultrasonic probe and reactor design for microbial inactivation.
• Comparative analysis of treated sour cherry juice against conventionally pasteurized samples.

Main Results:

• The combined microwave-ultrasonic treatment significantly better preserved qualitative properties compared to conventional pasteurization.
• Specific improvements noted: 14% higher vitamin C, 1% higher total phenolics, and 6% higher total anthocyanins.
• Optimal processing conditions identified: 541.7 W microwave power, 41°C, 799.57 W ultrasonic power, and 6 min ultrasonic exposure.

Conclusions:

• Combined microwave and ultrasonic processing offers a superior method for preserving sour cherry juice quality.
• The developed automated system and optimized conditions provide a promising approach for the food industry.
• This method effectively mitigates quality loss associated with traditional thermal pasteurization.