青ウメの常温貯蔵におけるエチレン除去剤とポリエチレン密封包装の影響

Abstract

The effects of packaging with polyethylene bags and the inclusion of ethylene absorbent and/or CO2 absorbent on the keeping quality of mume (Japanese apricot) fruits were investigated. Concurrently, the concentrations of oxygen, carbon dioxide, ethylene, ethyl alcohol, and acetaldehyde in the bags and their production by the fruits were monitored.1. Yellowing and softening of green mume fruit were noticeably retarded by the combination of packaging with polyethylene bags (0.02 mm) and the inclusion of an ethylene absorbent. This retardation of the ripening process was reversed when a carbon dioxide absorbent was included.2. The inclusion of ethylene absorbent in the bags kept ethylene concentration at very low level, whereas oxygen concentration was higher and carbon dioxide concentration lower compared with bags in which the absorbents were omitted. In sealed bags with carbon dioxide absorbent or without both absorbents, acetaldehyde and ethyl alcohol accumulated, resulting in a physiological disorder known as internal browning. Addition of the ethylene absorbent suppressed the accumulation of both volatiles and prevented the occurrence of the internal browning. Inclusion of carbon dioxide absorbent with ethylene absorbent negated the beneficial effect of the latter and resulted in the accumulation of volatiles which induced the physiological disorder.3. The respiration rate of the fruit was slower in sealed polyethylene bags with ethylene absorbent than in that without the absorbent; this suppression of respiration was overcome by the inclusion of the carbon dioxide absorbent. The ACC (1-aminocyclopropane-1-carboxylic acid) content in the fruit changed, parallelling the trends of ethylene evolution in all treatments. Among the different treatments, the ethylene forming enzyme (EFE) activity was lowest in fruits sealed in polyethylene bags containing the ethylene absorbent.