Maintaining Quality of Fresh-Cut Kiwifruit with Volatile Compounds
Kiwifruit (Actinidia deliciosa) were cut into 5 mm slices and placed in polystyrene trays. Various volatile compounds were introduced inside the trays before the lids were covered. The development of decay and the shelf life of the slices were evaluated during storage at 10 °C. Kiwifruit slices treated with 2.24, 11.2, or 22.4 µl l-1 methyl jasmonate maintained good quality after 3 weeks at 10 °C compared to the control slices. Comparable results were obtained with absolute ethyl alcohol (300 µl l-1) or isopropyl alcohol (300 µl l-1). However, 1-propanol was less effective and methyl alcohol was not effective in maintaining the quality of kiwifruit slices. Methods of application affected the efficacy of the volatile compounds. In general, suspension of the source of volatile compounds within the trays yielded better results compared to volatilization of the volatile compounds from beakers placed inside the trays. In addition to having less decay, kiwifruit slices treated with methyl jasmonate also maintained higher levels of sugars and organic acids compared to the untreated slices. Measurement of oxygen and carbon dioxide concentrations in the trays indicated that oxygen never dropped below 19.5% and carbon dioxide remained at approximately 0.8% in all treatments during the 3 weeks at 10 °C. No differences in respiration rates between methyl jasmonate treatment and control were detected. Ethylene production increased during the first 7 days and then decreased gradually. However, no differences in ethylene production between methyl jasmonate treatment and control were found.