470 Ethylene Inhibits the Development of Chilling Injury in Fresh-cut Tomato Slices during Storage at Low Temperature

Abstract

Experiments were conducted to determine if ethylene influences chilling injury, as measured by percent of slices showing some water-soaked areas and associated fungal growth in fresh-cut tomato slices (Lycopersicon esculentum Mill.; cvs. Mountain Pride and Sunbeam). Ethylene concentration in containers without a perforation (perforations were made by piercing the lid of the container forming a 0.7-mm hole) significantly increased during storage at 5 °C, while little or no accumulation of ethylene occurred in containers with from one to six perforations. Chilling injury was greatest in slices in containers with six perforations, compared to slices in containers with one perforation an,d was over 12-fold greater than that of slices in control containers with no perforations. The percent ofage visible fungal growth of slices was roughly correlated with the degree of chilling injury. An experiment was also performed to investigate the effectiveness of including an ethylene absorbent pad in containers on subsequent ethylene accumulation and chilling injury. While ethylene in the no-pad control increased continually during storage at 5 °C under modified-atmosphere conditions, no increase in accumulation of ethylene was observed in containers containing ethylene absorbent pads throughout storage with `Sunbeam' and `Mountain Pride' tomatoes. The ethylene absorbent pad treatment resulted in a significantly higher percent of chilling injury and visible fungal growth compared with the no-pad control. In studies aimed at inhibiting ethylene production using 1-aminoethoxyvinylglycine (AVG) during storage of slices, the concentration of ethylene in control containers (no AVG) remained at elevated levels throughout storage compared to containers with slices treated with AVG. Chilling injury in controls was 5-fold greater than that in slices treated with AVG. All slices treated with AVG had visible fungal growth, while the percent of slices showing visible fungal growth in no-AVG controls was 54%. Furthermore, we tested the effect of ethylene pretreatment of slices on subsequent slice shelf-life and quality. In slices treated with ethylene (0, 0.1, 1, and 10 μL·L-1) immediately after slicing, ethylene production in untreated controls was greater than that of all other ethylene pretreatments. However, pretreatment of slices at 3 days after slicing resulted in a different pattern of subsequent ethylene production during storage. The rate of ethylene production by slices treated with 1 μL·L-1 ethylene at 3 days after slicing was greater during storage than any of the other ethylene treatments. With slices pretreated with ethylene both immediately and 3 days after slicing, the rate of ethylene production tended to show an negative correlation with chilling injury.