In a world driven by innovation, novel non-thermal food safety intervention technologies are gaining ground.
While it's a fact that such technologies are gaining popularity, it may be mentioned that consumer interest in health and wellness prompted the food industry to develop technological solutions for preserving heat-sensitive functional foods with extended shelf life. In this regard, the food industry has been investigating several alternative food preservation techniques, according to a section of food technologists.
Extensive research is being undertaken at the Defence Bio-Engineering and Electrometrical Laboratory at the Defence Research Development Organisation, Bengaluru, University of Nebraska and Stansted Fluid Power UK.
Spectrum of tech
These cover the entire spectrum of advanced thermal processing known as Ohmic heating, Microwave heating and Radio Frequency heating and non-thermal food preservation methods such as High Pressure processing (HPP), Pulsed Electric Field processing (PEF), Irradiation, Ultrasound treatment, Ultraviolet processing, Ozone treatment and Cold Plasma treatment. Technologies like nanochitosan emulsion for antimicrobial coating in the application for preservation of food material and ultra high pressure homogenisation equipment are also devised.
There are several recent applications in advanced thermal and non-thermal intervention technologies that can be used for extending the shelf life of foods, quality and nutritional value of foods. It also covers the technology principles, equipment, microbial efficacy and food quality, according to Harshavaradhan Thippareddi, associate professor, and food safety extension specialist, department of food science technology, University of Nebraska.
While several technologies have been investigated, some of the technologies have gained wide acceptance in the food processing industry. The notable ones are HPP, PEF and UV light processing.
Evaluating potential
Investigations are underway to evaluate the potential for application of cold plasma technology for application to specific products such as fruits and fruit surfaces. While these technologies have applications in the food industry, they should be selected for specific applications as they may cause undesirable changes in some products. "HPP is widely accepted and used currently in the ready-to-eat meat and poultry processing industry to control Listeria monocytogenes. It can also improve the safety of fresh oysters and enhance the shelf life of avocado pulp," he said in a presentation on food technologies organised by the Defence Food Research Laboratory (DFRL), Mysore.
Similarly, UV light is being used in fruit juices, especially apple juice for destruction of food-borne pathogens such as Salmonella and E. Coli.
"Pulsed electric fields have been developed for application to liquid foods such as milk and fruit juices. Now we need to look at each of these technologies in terms of mechanism of action, efficacy and specific application to foods to improve their safety," he added.
Defence Bio-Engineering and Electrometrical Laboratory at the Defence Research Development Organisation has developed the nanochitosan emulsion for antimicrobial coating in the application for preservation of food material. The nano emulsion can be used to coat the fruits and vegetables to extend the shelf life and appearance, according to the scientists.
Stansted's range
Stansted Fluid Power has developed a range of systems customised to the requirements of HHP (high hydrostatic pressure) processing for both pasteurisation and sterilisation. The application of ultra high pressure homogenisation for food applications have included a wide variety of liquid products covering milk, fruit juices, vegetable extracts and flavourings where effects of micro organisms, creation of finer and more stable emulsions, active ingredients encapsulation and product sterilisations are developed. These advances are from technical abstracts on Innovative Techniques in Food Processing and Preservation published by the DFRL.