| This research was done over two seasons. The first season was intended to determine the effect of different storage temperature on the storability of 'Friar' plum fruit and to discern which temperature stores well without pre-storage treatment. Wholesalers in Hangzhou use 8℃ and the fruit stores for over 2 months. The second season's research was based on the findings in the first season.For both seasons, fruits were obtained from an orchard in Zhuji County, Zhejiang province and transported to the laboratory' in Hangzhou within one day.During the first season, fruits were stored at 0, 6 and 12℃ following pre-storage treatments. Parameters analyzed included respiration rate, ethylene evolution, firmness, weight loss, total soluble solids, titratable acidity, the antioxidant enzymes (superoxide dismutase, peroxidase and catalase), hydrolytic enzymes (polygalacturonase and Cx-cellulase), as well as the determination of the extent of chilling injury and decay indices. Chilling injury symptoms were found only in fruits stored at 0"C, while decay was much advanced in fruits at 12℃ than in fruits stored at 6℃. Respiratory increases coincided with decline in fruit firmness and an increase in PG and Cx cellulase activities for fruits held at 6 and 12℃. Fruits at 0℃ maintained low respiratory rate, greater firmness and lower cell wall hydrolase activities. Antioxidant enzyme activities continuously increased for fruits held at 0℃ except for Superoxide dismutase. Superoxide dismutase (SOD) tended on a decline for all treatments by day 45, with fruits at 0℃ maintaining highest enzyme activity, peroxidase (POD) enzyme activity stayed lower than that of SOD and declined after 45 days for fruits stored at 6 and 12T. Catalase (CAT) activity increased but declined after 30 days of storage for fruits at 6℃ and after 45 days for fruits held 12℃. Apart from chilling injury symptoms, fruits at 0℃, unaffected by Cl, were better for all ripening and internal quality characteristics. Fruits at 12 ℃ were dehydrated and wrinkled, while fruits 6℃ were better in physical appearance. By the end of the storage period, fruits at 6 and 12℃ were very much unfit for market, while those at 0℃ that were not affected by CI were still fit for market, suggesting that if Cl can be controlled, then 'Friar' plum can store at 0℃ for over three months as has been earlier reported. If,however, refrigeration is the only means available to prolong storage period and preserve fruit quality, temperatures above 0℃ and below 6℃ would be recommended.In the second season, fruits were HWD-treated at 40, 45, 50 and 55℃ prior to storage at 0℃. Respiration rate, ethylene production, fruit firmness, weight loss, total soluble solids, titratable acidity, hydrolytic enzymes (polygalacturonase (exo-and endo-PG), Cx-cellulase, pectinmethylesterase, p-galactosidase, and endo-glucanase), polyamines (spermine, spermidine, cadaverine and putrescine) and cell wall components (water-soluble pectin fraction, EDTA-soluble pectin fraction, sodium carbonate-soluble pectin fraction, 1 M KOH-soluble pectin fraction, 4 M KOH-soluble pectin fraction and a-cellulose fraction, were the parameters analyzed. Chilling injury and decay symptoms were also evaluated to determine the extent of the effect of hot water dip treatments.Initial respiration rates for all treatments dropped to significantly lower levels after one week of storage until removal from cold storage. The respiration rates took an increasing trend after 35 days resulting in the production of peaks by day 41.Following hot water dips ethylene levels for heat-treated fruits increased above that of control. One week after cold storage, ethylene levels for 45 and 50℃-treated fruits dropped below those of control, 40 and 55℃-treated fruits. All treated fruits as well as control variably peaked out 6 days after removal from cold storage.Initial fruit flesh firmness was lower for all treatments than control fruits. Firmness levels for 40 and 55℃ treated fruits increased together with 4...
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