Quality assurance of functional food products using physical field-assisted freezing

The quality of functional food products depends on the content of biologically active compounds throughout their shelf life. Freezing provides a significant increase in the shelf life of food products. At the same time, conventional food preservation by freezing appears to diminish the content of functional ingredients due to food structure damage and oxidation. This leads to significant losses of biologically active substances and a reduction in the product's biological activity. Depending on the type of biologically active substance these losses can reach 80%. Enhancing functional ingredients stability is suggested to be achieved using field-assisted freezing techniques. Electromagnetic field-assisted freezing improves retention of L-ascorbic acid in comparison with conventional methods, while ultrasound-assisted freezing improves total phenol retention by 15%, minimizes drip loss, and reduces lipid oxidation. Reported effects vary substantially with processing settings, and evidence for functional food products is still sparse, calling for ingredient- and matrix-specific studies.