Physics About Heat and Mass Transfer During Power Ultrasound-Enhanced Green Food Processing
Yue Wu1,2, Shunyu Yao2,3, Thivya Perumal4
1College of Food Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu, China.
Summary
Power ultrasound enhances food processing by improving heat and mass transfer, leading to increased efficiency and reduced resource use. This technology offers a greener approach to extraction, purification, and drying, optimizing food production.
Area of Science:
- Food Science and Technology
- Chemical Engineering
- Acoustics
Background:
- Power ultrasound is an emerging technology with potential to improve food processing.
- Enhancement of heat and mass transfer is key to improving efficiency and reducing resource consumption in food processes.
- Current food processing methods face challenges in efficiency, time, quality loss, and resource consumption.
Purpose of the Study:
- To investigate the ultrasonic intensification of heat and mass transfer in food processes.
- To focus on solvent extraction, purification (adsorption/desorption), and drying.
- To utilize computer-aided modeling and mathematical models to understand the underlying mechanisms.
Main Methods:
- Application of power ultrasound to food extraction, purification, and drying.
- Computer-aided modeling and mathematical modeling (based on Newton's, Fick's, and Fourier's laws) to visualize and study heat/mass transfer and cavitation.
- Experimental methods combined with physical and physicochemical models.
Main Results:
- Power ultrasound significantly improved the efficiency of food extraction, adsorption/desorption, and drying.
- Enhanced heat and mass transfer, driven by mechanical and cavitation effects, were identified as the primary mechanisms.
- Numerical simulations provided insights into cavitation characteristics (bubble lifespan, size, number) and process behavior.
Conclusions:
- Power ultrasound effectively enhances heat and mass transfer, leading to improved efficiency and reduced processing times in various food applications.
- Numerical simulations are valuable tools for understanding ultrasound-enhanced food processes, optimizing parameters, and facilitating scale-up.
- The application of power ultrasound presents a promising, greener alternative for food processing.
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