Non-electro-Technologies: Gamma Rays, UV Light, Ozone, Photodynamic and Membrane Processing

Non-electro technologies (NET) refer to the non-thermal physical preservative techniques that employ low or ambient temperature to enhance the shelf-life of wide-ranging agro-produces. Processing of food products using gamma rays (wavelength, λ <100 pm), ultraviolet (UV) light (λ: 100–400 nm), ozonation and membrane processing fall under the above category. Compared to conventional thermal processing techniques, non-electro technologies result in greater retention of nutrients and other volatile contents in the treated food product. The first part of the chapter would elaborate on the gamma-ray processing of foods and its applications in the disinfection of fruits, treatment of drinking water, disinfestation of cereals and sterilization of meat and poultry products. Further, physicochemical characteristics of treated products and safety aspects of any food irradiation technology concerning gamma-ray processing will be discussed. The next part of the chapter would comprehensively review the principle of food preservation by UV light and its applications in the food processing sectors. Next part of the chapter deals with ozone, in which ozone gas is used to decontaminate the food surfaces. Ozonation has been extensively utilized for enhancing the shelf life of comprehensive range of agro produces. It is also used for the dissipation of pesticide residues from food products. Finally, the chapter discusses about membrane technology, which is widely used for concentration of fruit juices and other liquid foods to increase the shelf life of final liquid product. This entire chapter critically analyzes the technologies, equipment principles, its characterization and applications in food and agriculture sector, emphasizing the main advantages and shortcomings in terms of their impact the safety, nutritional, and health properties of food products. Moreover, the general discussion also covers the analysis of the energy consumption and sustainability aspects associate to the different technologies, and conclude with the recent advancements and future perspectives.