Influence of heat treatment in water on changes of tomato properties during postharvest storage at low temperature

Abstract

Storage of tomato after harvest at low temperature in order to prevent decay and prolong its postharvest shelf life induces chilling injuries and makes fruit susceptible to the colonization of microorganisms that can cause fruit deterioration. One of postharvest treatments used for reducing of chilling injuries is the heat treatment in water or in the air flow. In order to investigate influence of heat treatment in water on properties of tomato stored at low temperature (4°C) during three weeks, commercia l tomato was harvested at mature green and red-ripe stages. Tomato harvested in mature green stage was treated in water at 42°C for 1 h. Samples of treated and non treated to mato harvested in mature green stage, as well as sample of non treated tomato harvested in red-ripe stage were stored at 4°C. Tomato ripening was monitored once a week by instrumental measurement of fruit color using Minolta Chroma Meter CR-400. After three weeks of cold storage, all tomato samples were evaluated by sensory panel consisting of 10 trained assessors. Differences between treated and non treated tomato samples were observed and compared with properties of red-ripe harvested tomato. It was concluded that heat treatment in water of 42°C for 1 h results in less chilling injuries, delayed but more uniform development of red color, less presence of vessels, and lower intensity of non-characteristic odor and taste.