Power and temperature distribution during microwave thawing, simulated by using Maxwell's equations and Lambert's law

An Integrated Approach of Mechanistic-Modeling and Machine-Learning for Thickness Optimization of Frozen Microwaveable Foods

Mechanistic-modeling has been a useful tool to help food scientists in understanding complicated microwave-food interactions, but it cannot be directly used by the food developers for food design due to its resource-intensive characteristic. This study developed and validated an integrated approach that coupled mechanistic-modeling and machine-learning to achieve efficient food product design (thickness optimization) with better heating uniformity. The mechanistic-modeling that incorporated electromagnetics and heat transfer was previously developed and validated extensively and was used directly in this study. A Bayesian optimization machine-learning algorithm was developed and integrated with the mechanistic-modeling. The integrated approach was validated by comparing the optimization performance with a parametric sweep approach, which is solely based on mechanistic-modeling. The results showed that the integrated approach had the capability and robustness to optimize the thickness of different-shape products using different initial training datasets with higher efficiency (45.9% to 62.1% improvement) than the parametric sweep approach. Three rectangular-shape trays with one optimized thickness (1.56 cm) and two non-optimized thicknesses (1.20 and 2.00 cm) were 3-D printed and used in microwave heating experiments, which confirmed the feasibility of the integrated approach in thickness optimization. The integrated approach can be further developed and extended as a platform to efficiently design complicated microwavable foods with multiple-parameter optimization.

Microwave Food Processing

Consumers prefer food products with enlarged shelf life, which are quick to prepare, healthy and fresh like. Traditional food processing methods are based on intensive heating and as a result cause quality loss. Minimal processing techniques such as microwaves approach consumer's demands to create fresh like products with enlarged shelf life. Microwave technology can be very useful for food processing, because products are heated directly instead of conventional heating by convection and conduction. This means a reduction of the total processing time, no overheating on the outside of the product, and preservation of the fresh product quality. This chapter presents a complete picture of current knowledge on application of microwave in food processing which has been used for different processes like blanching, sterilisation, thawing, drying and extraction of various products. In many cases combinations with microwaves gave the best results.