# Applications of Pulsed Light Decontamination Technology in Food Processing: An Overview
## 1 Introduction  
Currently, there is a growing concern for nutrition and food safety. Modern technology and access to the internet has made the 21 st-century consumer more aware and demanding than ever before. They want safe, sound, and healthy foods of good quality, having an adequate supply of required nutrients, but devoid of any preservatives [1]. Conventionally, the food industry has used preservatives or thermal processing for the extension of shelf-life. The deleterious effect of heat on the nutritional attributes and sensory qualities of food is now common knowledge [2, 3], and the food industry is experiencing a paradigm shift towards minimal and non-thermal technologies. This has prompted food processing researchers to develop various technologies like ohmic heating, radiofrequency (RF), microwave (MW), and infrared (IR) heating, high pressure processing (HPP), ultrasound (US), pulsed electric field (PEF), pulsed light (PL), cold plasma (CP), oscillating magnetic field (OMF) etc. as alternates to the conventional thermal process. These technologies have the potential to gradually replace the thermal methods practiced by the foodindustry, especially because they are carried out at ambient and sub-lethal temperatures; and in this way are disposing of the antagonistic impacts of thermal technologies. Each of these novel technologies constitutes an altogether separate field of studies themselves. However, the purpose of this literature review is to study and intimate the readers regarding the critical fundamentals and applications of pulsed light (PL) technology in food processing. PL treatment generally consists of applying a series of high intensity, short bursts of light pulses to kill microorganisms. PL is synonymous with the terms pulsed ultraviolet light (PUV), intense light pulse (ILP), high-intensity broad-spectrum pulsed light (BSPL), high-intensity pulsed UV light (HIPL), or pulsed white light (PWL) [4; 5]. PL has a great potential to enhance the keeping quality of food products [6; 7] by destroying microorganisms such as _Listeria monocytogenes_ within a few seconds [1]. PL was successful in reducing the total microbial load in vitro when inoculated on the surface of agar plates [1]. So, it can be claimed to have the potential to preserve food materials. Also, PL technology can be effectively used to sterilize packaging materials [8], and equipment surfaces [9; 10]. However, PL technology has its limitations to be used for food applications due to the opacity of food products and their non-uniform surfaces, and possible temperature rise (due to the effects of the infrared region) leading to deterioration in organoleptic qualities. In 1996, the U.S. Food and Drug Administration (FDA) approved the PL technology applications 'for the production, processing and handling of foods' and decontaminating food contact surfaces [11]. They recommended the use of PL treatment using xenon lamp having surface emission of wavelengths (\(\lambda\)) between 200 and 1100 nm, with the cumulative treatment not more than 12 J/cm\({}^{2}\) and pulse width not greater than 2 ms [4]. Since then, a considerable increase in research and development in the field of PL technology in food industry has taken place. As a result, more than 250 articles, including reviews, patents, and chapters have been published. Figure 1 shows a steady rise in publications after the year 2000. Numerous PL systems and configurations have been manufactured. Successful intervention for decontaminating fresh-cut fruits and vegetables, meat surfaces, equipment-contact surfaces, and clear liquid foods. Efforts are being made to extend it to turbid and opaque liquid foods, seeds, powders, ready-to-eat meals, and other thermally labile food commodities. With the growing demand for safe and nutrient-rich foods, thorough research should make the process ready to be adopted by the food industry sooner or later. Figure 1: Increase in the number of publications in the field of pulsed light.