Changes in the contents of low molecular weight carbohydrates and organic acids in fruit-bodies of maitake-mushroom (Grifola frondosa) during non-packaging storage and hermetical storage (polyethylene film bags 100μm thickness) at five storage temperatures (0, 5, 10, 20 and 30°C) were investigated. (1) The shelf lives of non-packaging storage of maitake-mushrooms were 7 days at 0°C, 5-6 days at 5°C, 4-5 days at 10°C, 3-4 days at 20°C and 2-3 days at 30°C. The shelf lives of hermetical packaging storage of maitake-mushrooms were 7 days at 0°C, 6-7 days at 5°C, 5 days at 10°C, 3-4 days at 20°C and 2 days at 30°C, and hermetical packaging storage was not effective to extend the shelf lives. (2) In this mushroom, mannitol, arabitol, glycerol, trehalose and glucose were identified, and mannitol and trehalose were found to be major among them. During storage, the contents of each element except mannitol decreased. Especially the decrease in trehalose was marked, and trehalose may be functioning as the major respiratory substrate. (3) In this mushroom, formic, acetic, lactic, oxalic, succinic, fumaric, malic, pyroglutamic and citric acids were identified, and among them malic, pyroglutamic, fumaric, citric and acetic acids were found to be major. The contents of malic, oxalic and citric acids in fruit-bodies increased during storage at five storage temperatures with the elapse of storage days and the rise of storage temperatures.

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To know the best method for the long-term storage of ginkgo nuts, the storage trials of the nuts were carried out under 3 different CA conditions ((1) Oxygen 5%, Carbon dioxide 5%, (2) Oxygen 3%, Carbon dioxide 6%, (3) Oxygen 3%, Carbon dioxide 10%) at 0.5°C and 90% relative humidity for 240 days.
1) Ginkgo nuts lost marketability because of endosperm Shrivelling when the weight of the nuts decreased more than around 10% of the initial weight. The weight loss of the nuts exceeded 10% before less than 150 days of storage when stored without humidity control but did not exceed 10% at 90% relative humidity even after 240 days.
2) Both blemishing by mold spores of nuts shell and degreening of endsperm could be effectively prevented by CA storage combined with 90% of relative humidity and low temperature (0.5°C).
3) These storage condition was also effective for preservation of ascorbic acid, chlorophyll and sugars.
4) Cotyledons of the nuts grew a little after 240 days of CA storage. However, marketability was not affected by this growth of the cotyledon.
Based on these results, we concluded that ginkgo nuts can be stored for a long time under the CA conditions with low temperature (0.5°C) and 90% of relative humidity.

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The changes in water loss, membrance permeability and ultrastructure of Hassaku fruits (Citrus hassaku Hort. ex. Tanaka) were conducted in various storage temperatures. The results showed that storage temperature was an important factor affecting on the water loss, membrane permeability and the occurrence of rind-oil spot symptom. With a scanning electron microscope (SEM), the temperature also induced the ultrastructural changes of surface wax. The marked increases in membrane permeability and changes in ultrastructure of peel were observed in fruits stored at 10°C for 90 days and throughout this investigation period. Broken oil glands were observed on the peel of fruits stored at 10°C for 30 days and more notices when kept for a longer period of time. Moreover, the increases in wax were observed on the peel of fruits stored at 10°C and 20°C for a longer period of time, which were parallel to the occurrences of rind-oil spot symptom, except for the fruits stored at 0°C. The relationships among the ultrastructural changes of peel, membrane permeability and the occurrences of rind-oil spot symptom are discussed.

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The qualities of tomato fruits cultivated by hydroponics (HT) were compared with those cultivated on soil (ST) purchasing from a wholesale market in Osaka.
There was little difference between HT and ST concerning with maturity and size, but ST were sold at higher market price than HT. The difference of price, however, was not due to cultivation method, but was owing mainly to long-standing custom of trades and stable supply from growers in soil culture districts, according to the hearing from wholesale dealers.
HT contained higher free amino acids than ST, but it did not show any significant differences in pH, Brix, and contents of total sugar, reducing sugar, ascorbic acid, and titratable acid from ST.
Panelists could not recognize apparent differences of color, aroma, sweetness, acidity, texture, and preference between both tomatoes in organoleptic evaluation.

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