The Use of Mild Heat Treatment for Fruit and Vegetable Processing

Currently available washing and sanitizing methods for fruit and vegetables, including some of the newest sanitizing agents, are not totally effective. Certain washing and disinfection treatments may also negatively affect the nutritional and sensory quality of produce and there are environmental and health risks posed by the use of some chemical disinfectants. Mild heat treatments, however, do not use harsh chemicals, are environmentally friendly, and have been successfully utilized to improve postharvest storage of a range of fresh-cut fruit or vegetables. Heat treatment has been shown to successfully reduce microbial loads; it improves the quality and shelf life of fresh-cut products, reduces chilling injury, and retains texture. There is a growing interest in the use of heat treatment to also control insect pests, prevent fungal rots, and retard or minimize commodity response to temperature extremes. Successful dipping will depend on the commodity, origin, cultivar, size, and processing history, and dipping can be optimized by careful selection of dipping time and temperature. The addition of calcium can enhance the beneficial action of mild heat treatments on sensory properties of processed fruit and vegetables.