Alleviation of chilling injury (CI) of Ponkan fruits (Citrus reticulata BLANCO) during and after low temperature disinfestation (at 1±0.2 °C, for 15-16 days) was investigated by treatment with a 0.35% solution of sucrose fatty acid esters (CT-1695, L-1695, M-1695, P-1695, S-1695 andO-1695). The occurrence of CI of the fruits was suppressed by treatment with all types of sucrose fatty acid esters. Among the used esters, M-1695, P-1695 and S-1695 esters were more effective to alleviate CI. The treatment with M-1695, P-1695, S-1695 and O-1695 tended to restore the lowering of the respiratory rate of the fruits during holding at 1°C and subsequent storage at 20 °C. Changes in fruit weight, ratio of juice volume to fruit weight and titratable acidity were inhibited by the treatment with the esters. Results judged from an organoleptic test (20 panels) indicated that the fruits treated with M-1695 and P-1695 showed significantly better appearance and the fruits treated with M-1695 showed better taste than the others. Judging from the above results, the treatment with 0.35% sucrose myristate (M-1695), palmitate (P-1695) and stearate (S-1695) esters seems to be useful to alleviate CI of Ponkan fruits during and after low temperature disinfestation.

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Quality of sous vide processed potatoes was studied in relation to the differences of processing temperatures (70, 80, 90 or 100°C) and degrees of vacuum (30 or 100Torr) in packaging. In addition, quality changes in sous vide processed potatoes during storage was also investigated. When processed at 80°C or higher temperatures, potatoes showed no changes in surface color in all treatments. Browning, however, occurred in processing at 70°C. There were no appreciable differences between the hardness of potatoes and the degree of vacuum during processing at 80 or 90°C. In the processing at 100°C, potatoes remained harder with a lowering of the degree of vacuum while those packaged under atmospheric pressure remained hardest. The content of total ascorbic acid in potatoes was kept higher during processing at 90 and 100°C. The content in packaged potatoes was higher than that in the conventional processing potatoes. Dehydroascorbic acid content showed almost the same value in all the treatments. There was no considerable difference between the sugar content and the degree of vacuum in packaged potatoes. The sugar content in the conventional processing, however, was lower when compared with that of the processing at 80 or 90°C of packaged potatoes. Anaerobic bacteria were detected after 3 days of storage at 20°C. Potatoes were putrefied after 3 days of storage at 20°C. No bacteria were detected for 7 days of the storage when stored at 5 or 10°C. Dehydroascorbic acid content increased during storage at all temperatures. Changes of reducing sugar content showed a similar tendency at all of the storage temperatures and increased slightly during storage. It is suggested that sous vide processing at 90°C or higher temperatures is good for the storage of potatoes and that storage at 5°C or a lower temperature is good for quality.

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Quality of sous vide processed green peas were studied in relation to the differences of processing temperatures (80, 90 or 100°C) and degrees of vacuum (30 or 100 Torr) in packaging.Additionally, changes in quality during storage were also investigated. The surface color of sous vide processed green peas at 100°C was better than that with other processings. There were no considerable differences among processing temperatures on the total chlorophyll content. The content of total ascorbic acid, total sugar and soluble nitrogen compounds in sous vide processed green peas was higher than those in the green peas by conventional processing. Anaerobic bacteria increased after 4 days of storage at 20°C. The green peas were putrefied after 7 days of storage at 20°C. No bacteria were detected after 11 days of storage when the green peas were stored at 5°C. The surface color was discolored during storage, especially at 20°C, with a degradation of chlorophyll a. The ascorbic acid content showed no change during storage at 5 or 20°C. The total sugar content showed almost the same value at 5 or 20°C, and slightly decreased during storage. These results indicated that cooking under reduced pressures at 90°C or higher temperatures is good for the quality of green peas. Furthermore, it is also suggested that storage at 5°C or lower temperatures is good for maintaining quality.

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To study the relationships between various components and the hardness of 'Koumezuke' [a small type mume (Japanese Apricot, Prunus mume SIEB, et Zucc)], we analyzed the Ca, Mg and pectin content, and also measured the hardness of 'Kaoumezuke' that has been brined at various factories. The binding properties of Ca or Mg to certain components of AIS (alcohol insoluble substances) in two different types of pickled mume fruit, 'Koumezuke' (a salted product) and 'Koumeboshi' (a dried salted product), were characterized as Ca >> Mg. In 'Koumezuke', the ratio of HSP (0.05N-hydrochloric acid-soluble pectin) against total pectin decreased and PSP (0.4%-hexametaphosphate-soluble pectin) increased during brining and both ratios showed a slight change after the eighth day of brining. The HSP/WSP (H/W) ratio of 'Koumezuke' and 'Koumeboshi' was 10.1 and 0.48, respectively. The HSP of Koumeboshi was hydrolyzed by acids concentrated during a sun-dried process, and HSP changed mainly to WSP, and the mume fruit softened in texture. There was a significant correlation between the hardness and H/W ratio of 'Koumezuke' at 1% level significance. In the cases where H/W ratio was under 16, coefficient correlation (r) was found to be 0.972, and a simple regression equation was H = 51.4R +186. No significant correlation was found between the content of Ca, Mg and the hardness of 'Koumezuke.' 'Koumezuke' softened in texture when the fruit was stored in solution containing a salt concentration of less than 10.7%, an acid concentration of more than 2%, and at temperatures above 30°C 'Koumezuke' softened in texture by the addition of organic acids in the order of citric acid> malic acid>lactic acid.

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Rates of carbon dioxide and ethylene production in broccoli were measured during storage at 20, 10, and 5°C. A climacteric-like temporary increase in carbon dioxide and ethylene production were observed in the storage at 20°C. These increases were more remarkable in flower buds rather than the stalk of broccoli. Contents of 1-aminocyclopropane-l-carboxylic acid (ACC) and 1- (malonylamino) cyclopropane-1-carboxylic acid (MACC) in the flower buds increased slightly during storage at 20 and 10°C, but this increase in ACC content did not coincide with the dramatic increase in ethylene production. Changes in activity of ACC oxidase (Ethylene forming enzyme) and the ACC malonyltransferase associated with conversion of ACC to MACC in flower buds during storage at 20t were more remarkable than those during storage at 10°C. The change in the activity of ACC oxidase in flower buds during storage at 20°C coincided with the change in ethylene production.

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