Radio frequency pasteurization and disinfestation techniques applied on low-moisture foods

Abstract

The shelf life of foods is usually limited due to the frequent contamination by pests and microorganisms. Although low risk of pathogen contamination and no growth potential compared to those in high water activity animal- or vegetal-derived products, the low-moisture food has still significantly contributed to the total number of foodborne infections and outbreaks. Radio frequency (RF) treatments can be classified as a dielectric heating, which is a promising technology for achieving effective food pasteurization and disinfestations because of the associated rapid and volumetric heating with large penetration depth. The RF technique could be applied at low-moisture food as both the dipole dispersion and ionic conductivity may play effective roles. It can selectively heat and kill the microorganisms/pests without damaging the agricultural product because of the large difference of dielectric loss factors between target microorganisms/pests and host foods. In this article, the low-moisture foods sterilized and disinfested by RF energy are reviewed through basic theories, dielectric properties, heating effect, and uniformity. The potential research directions for further RF heating applications are finally recommended in low-moisture foods.

Keywords:

• Radio frequency
• Pasteurization
• Disinfestation
• Dielectric properties
• Heating uniformity

Additional information

Funding

This research was conducted in the College of Mechanical and Electronic Engineering, Northwest A&F University, and supported by research grants from National Key Research and Development Program of China (2017YFD0400900), National Natural Science Foundation of China (31601485), China Postdoctoral Science Foundation (2016M602866), and Shaanxi Postdoctoral Science Foundation (2016BHSEDZZ101) and the Fundamental Research Funds for the Central Universities (Z109021620).