Studies on Microbial Destruction and Quality Characteristics in Beetroot Jamun Juice by continuous Microwave Heating System

<p>The continuous microwave processing system is one of the pasteurization techniques that offer good potential for high quality, reduced processing time and energy as compared with conventional techniques. Beetroot is one of the most consumed root vegetable worldwide due to its nutritional value. Jamun fruit has been reported to possess anti-inflammatory, antibacterial, anti-diabetic and anti-diarrheal effects. The blend of beet-root and jamun juice is a formulated health drink and the overall goal of this study was to process and preserve this blend juice through a continuous flow of microwave heating system with value addition. The objectives of this work are to study the effects of microwave heating on juice properties viz., physical-chemical, sensory, microbial count and engineering parameters during a storage period of 180 days. Storage studies showed that MW treatment caused insignificant variation in acidity and pH, slight increase in bacterial count. Continuous Microwave pasteurization system (15 l/hr) was developed using optimized experimental parameters. The achieved reduction of specific energy requirements of originally 0.7 kW-h per litre to 0.142 kW-h per litre makes the presented concept a process option which is highly energy efficient and can be easily integrated into existing food processing operations.