New processing technologies: an overview

Abstract

Most food-preservation techniques act by slowing down or completely inhibiting the growth of micro-organisms. Few techniques act by inactivating them. While heat remains the technique most extensively used for inactivation, there has been increasing interest recently in the development of alternative approaches in response to the desires of consumers for products which are less organoleptically and nutritionally damaged during processing and less reliant on additives than previously. The new approaches, therefore, mostly involve technologies that offer full or partial alternatives to heat for the inactivation of bacteria, yeasts and moulds. They include the application to foods of high hydrostatic pressure, high-voltage electric discharges, high-intensity laser and non-coherent light pulses, ‘manothermosonication’ (the combination of mild heating with ultrasonication and slightly-raised pressure), and high-magnetic-field pulses. In addition, a number of naturally-occurring antimicrobials, including lysozyme and low-molecular-weight products of micro-organisms are finding increasing use. High pressure is being used commercially to non-thermally pasteurize a number of foods, while the other physical procedures are in various stages of development and commercial evaluation. Possible nutritional consequences have so far been given little attention compared with microbiological ones.

Nonthermal Plasma Inactivation of Food-Borne Pathogens

“…New risks are being encountered because of changing characteristics of the relevant micro-organisms, changing production methodologies, changes in the environment and the ecology, and an increase of the global trade of food stuffs (Havelaar et al 2010). As consumer demands and food safety issues have changed, so have the food processing technologies (Gould 2001) to ensure food safety. Moreover, there are multiple issues relating to quality of thermally processed foods such as nutritional losses and adverse effects on organoleptic quality.…”

Food Safety Engineering: An Emergent Perspective

“…Such foods are being developed to a large extent in reaction to consumers. Requirements for foods more natural and therefore less heavily preserved (e.g., less acid, salt, sugar) and processed (e.g., mildly heated), less reliant on additive preservatives (e.g., sulfite, nitrite, benzoate, sorbate), fresher (e.g., chill-stored), and more convenient to use (e.g., easier to store and prepare) than previously [79] have led to the development of mild preservation technologies, which are gaining more and more importance with time. Examples include the aforementioned high-pressure processing, pulsed electric fields, light technologies, cold plasma, and use of biopreservatives.…”

Inactivation of Baroduric Bacteria Isolated by High Hydrostatic Pressure from Pickled Cowpea

“…As a result, the inactivation curves display two increasing stages. The vegetative cell of bacteria, mycete and saccharomycetes were inactivated at 200-600 MPa pressure at ambient temperature (Smelt, 1998), while some spores can survive under 1200 MPa pressure (Gould, 2001). Pressure resistance of spore wall could be diminished by auxiliary method, such as mild heat and bacteriostat, to impel germination of spores (Vercammen, Vivijs, Lurquin, & Michiels, 2012;Hang, 2012).…”