異なった温・湿度の子措処理が数種カンキツ果実の品質に及ぼす影響

Abstract

Effect of conditioning at different temperatures (1°, 5°, 10°, 15°, 20°, or 25°C) and hu-midities (high or low) for seven days after harvest on the quality of several cultivars of citrus fruits including Hassaku (C. hassaku Hort. ex Tanaka), Iyo (C. iyo Hort. ex Tanaka cv. Miyauchi), Natsudaidai (C. natsudaidai Hayata cv. Kawano), navel orange (C. sinensis Osbeck var. brasiliensis cv. Morita), Ponkan (C. reticulata Blanco cv. Ota) was investigated at the end of storage at 5° ±0.5°C 88±5%, RH.1. A high rate of weight loss was found in the fruits conditioned at higher temperature and lower humidity during the period of conditioning. However, the rate of weight loss of the fruits conditioned at high temperature and low humidity was less during storage at 5°C compared with those fruits conditioned at low temperature and high humidity. There was no significant effect of the conditioning on the rate of pulp weight to fruit weight or rate of juice volume to fruit weight.2. The conditioning affected changes in surface color of the fruits. The fruits conditioned at 15°C and low humidity showed the biggest change in color showing a bright orange color among the fruits conditioned differently. The biggest change in color next to the fruits con-ditioned at 15°C was fruits treated at 10°C. The fruits conditioned at 1° and 25°C showed almost no change in surface color.3. The fruit conditioned at 15°, 20° or 25°C had a high content of titratable acid (as citric acid) and a high Brix value at the end of storage. In contrast with those fruits, conditioned fruit at 1° or 5°C tended to contain a low level of acidity and Brix.From above mentioned results, it may be suggested that conditioning at a temperature rang-ing from 10° to 15°C is effective to improve quality of some varieties and cultivars of citrus fruits during long term storage.