The effects of several atmosphere compositions on respiration rates, chemical components and keeping quality of Welsh onion (Allium fistulosum L.) were investigated during storage at 15t. Carbon dioxide production from Welsh onion under continuous stream of air (the flow rate was 7 litter/hr) was 111mgCO₂/kg/hr, it being reduced under continuous streams of low oxygen and high carbon dioxide levels. Ascorbic acid, sugar and chlorophyll retention under low oxygen level were better than those in air. Sensory score of Welsh onion withering leaf tip was reduced under low oxygen and high carbon dioxide levels. From these results, atmosphere compositions such as 7.6% O₂ + 12.6% CO₂ and 4.1% O₂ + 17.1% CO₂ respectively, gave better keeping quality of Welsh onion while avoiding physiological injury.

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The time-course changes in the contents of free fatty acids in brown rice and milled rice one during storage were investigated by HPLC using 9-anthryldiazomethane (ADAM), a fluorescent reagent for the analysis of fatty acids. The major fatty acids in brown rice and milled rice were linoleic acid, oleic acid and palmitic acid and their contents increased with time of storage. Their increases were larger in milled rice than brown rice and this tendency was more marked for storage at a high temperature. When the values determined by HPLC using ADAM for the final samples collected from brown rice after 8-month storage and milled rice after 90-day one were compared with the acid values obtained by the conventional method, the correlation coefficients for brown rice and milled rice one were 0.876 and 0.991, respectively, indicating that there is a significant correlation between the two methods (P<0.01). The HPLC method using ADAM was found to be able to rapidly and quantitatively reveal the changes in the free fatty acids of rice associated with storage. These results indicated that low-temperature storage is essential for quality maintenance of brown rice and milled rice

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To hold a system of cooling transportation of fruits and vegetables at near 15°C in summer season, we made the simple spotted cooling unit (S.C.U.) with bellows structure. S.C.U. is suitable for a large subdivision platform in the collection and delivery center of fruits and vegetables, and in a wholesale market, in which cooling instruments have not been established because of hindering transfer or subdivision working of fruits and vegetables, and the temperature of them sometimes have risen. When some vegetables (spinach, carrot, sweet corn and shiitake mushroom) were stored within S.C.U. in summer season, no significant changes in the appearance observed for 30 hours which was the longest period of the stay in collection and delivery centers or in wholesale markets. No change in the appearance also was observed until for 10 hours leaving at the open. However L-ascoric acid (ASA) contents in spinach decreased 30-40% during leaving at the open for 6 to 10 hours which was ordinary stay time before redistribution. It is reported that ASA content decreases in vegetables after harvest before the appearance changes. Therefore, this decrease of ASA in the spinach indicates that the deterioration progressed rapidly during leaving at the open. On the other hand, only 10% of ASA decreased during storage within S.C.U. This result demonstrated the effectiveness of S.C.U. to preserve the quality of vegetables.

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The effect of alcohols and sugars on an increase in the activity at the low temperature of the trypsin and chymotrypsin was examined. The activity at the low temperature of both enzymes has increased by 2-propanol and ethanol addition.However, an activity increase was not observed in trehalose, glucose, and sucrose addition. The activity increased at the low temperature of about 10°C to which the activity decreased at about 40°C when 2-propanol addition from which an increase in the activity was especially seen was examined.
Moreover, the decrease in the temperature dependency was seen by the 2-propanol addition. It was guessed that the change took place in the structure of the enzyme because the hydrophobicity on the surface of the enzyme increased by 2-propanol addition, and the increase of the activity at the low temperature had been caused.

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Chinese cabbage (Brassica pekinenses (Lour.) Rupr.) is one of the most popular and largest quantity vegetables produced in Taiwan. Owing to the concentrated harvest in winter of this vegetable, the surplus always brings a big economical loss to farmers. On the contrary, the shortage of vegetables often occurs in rainy season such as spring and summer. How to process and preserve the vegetables harvested in winter and store them for consumption in the rainy season is a major problem in agriculture and food industry to be solved.
The purpose of this study is to develop a technique to minimally process Chinese cabbage so that it could be stored for a longer time. For this purpose the half cut Chinese cabbage was treated with a solution of 6.0% salt and 0.2% acetic acid under a vacuum of 70 cm-Hg for 16.5 min, then vacuum packed and stored at 5°C or-18°C. The organoleptic quality of the minimally processed Chinese cabbage stored at either 5°C or-18°C for 6 weeks were organoleptically acceptable. The quality (total plate count, lactic acid bacteria, pH, total acidity, vitamin C content, lightness, redness, green index) of the processed Chinese cabbage stored at-18°C for 4 months were found to be similar to that of the initial one.

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In a daily life the most common method for preservation of fresh food are by keeping them at a normal temperature, or by refrigeration or freezing of them.
This experiment was intended to show how the contents of the vitamins and water in frozen vegetables were changed during 12month preservation after freezing the fresh vegetables. The changes in contents of vitamins also were examined in the vegetables refrigerated after freeze-drying. In order to produce frozen, or dried or canned vegetables, the pretreatment which is essential at its initial step, called blanching, must be performed.
It is confirmed by the experiment that there is little loss of vitamins in case of frozen foods, and is understood that the same amount of vitamins in the frozen foods can be expected for one year as at the time of their production if preserved at-24°C.

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