Summary
High pressure processing (HPP) is gaining in popularity with the North American food industry because of its capacity to inactivate pathogenic microorganisms with minimal heat treatment, resulting in the almost complete retention of nutritional and sensory characteristics of fresh food without sacrificing shelf-life. Other advantages of HPP over traditional thermal processing include reduced process times; minimal heat damage problems; retention of freshness, flavor, texture, and color; no vitamin C loss; no undesirable changes in food during pressure-shift freezing due to reduced crystal size and multiple ice-phase forms; and minimal undesirable functionality alterations. Changes that may be made improve functional properties of food constituents resulting in value-added products. Minimization of damage during pressure-shift freezing and thawing using HPP; non-thermally-induced enzyme inactivation; and desirable changes in starch-gelatinisation properties are some other examples of potential benefits of HPP. However, spore-inactivation is a major challenge for HPP. Methods used to achieve full inactivation of spores using HPP are :-) to be developed. In thermal processing, D (time required in min to reduce the microbial population 10-fold), Z (temperature in °C yielding a 10-fold change in D), and Fo (the integrated lethal value from all heat received by a treated food with a reference temperature of 121.1°C and assuming a Z-value of 10°C) values are standard processing parameters, however there is a need to develop and standardize HPP process parameters with respect to microbial inactivation, because none exist. This is essential before commercialization of this technology can take place. In this paper, basic principles of HPP are explained and the major research done on various HPP applications around the world is critically evaluated. Recommendations are made for major research areas in HPP for commercialization of this technology.