Chapter 7 - Light-based processing technologies for food

Abstract

Light-based technology is a nonthermal technology used for inactivation of microorganisms in food processing. This technology utilizes the germicidal effect of light based on variable wavelength against bacteria, viruses, and fungi. The generation of UV and pulsed light is obtained from different sources such as mercury lamp, excimer lamp, xenon lamps, microwave UV lamp, and light-emitting diodes. Short duration and high power light pulses have been proved to be powerful enough for inactivating several pathogenic and spoilage microorganisms by a combination effect of photochemical, photothermal, and photophysical mechanisms. Pulsed light treatment is more commonly used and can also be combined with other technologies to provide a hurdle effect. Light-based technology is an alternative to thermal and chemical decontamination methods because of numerous benefits to improve and preserve the quality of various foods by resulting in minimal influence on the food quality attributes. In the last decade, light technology using UV found more applications in the food production chain due to it being an economic, effective, and versatile dry processing technology that has potential to improve safety and preservation quality of both solid and liquid foods. The electron beam ionizing radiation technology which is used for treating foods for phytosanitary purposes has also been discussed in this chapter along with the working principle, sources of UV and pulsed light, mechanism of microbial inactivation, applications of light technology for food safety, and preservation and related regulations.