Full ripe tomatoes were stored with or without an ethylene absorbent in polyethylene bags of 0.03mm, 0.05mm and 0.07mm thickness. This ethylene absorbent was prepared by treatment of activated charcoal with potassium bromate and sulfuric acid.
1. In the bags with ethylene absorbent, not only ethylene concentration but also the acetaldehyde concentration were lower the, i that the bags without absorbent (control).
2. When tomatoes were stored at 15°C, the unpackaged tomatoes lost its firmness in 4 days. Tomatoes, which were stored in 0.03mm or 0.05mm polyethylene bags without ethylene absorbent at 15°C, maintained its firmness for 11 days. The firmness of tomatoes with absorbent in the same condition surpassed the control.
3. Ethylene absorbent showed no effect in surface color and glutamic acid, glucose and fructose contents. Citric acid content of tomatoes decreased during storage while the decreasing rate was retarded by using absorbent.
4. While this ethylene absorbent can absorb water vapor to some extent, the weight loss was about 1% after 14 days at 15°C, showing no problem in trade.
5. Tomatoes in polyethylene bag tended to suffer from mold infection and physiological injury during the storage at 15°C. The usage of absorbent retarded these losses. Packaging in 0.03mm polyethylene bag with ethylene absorbent was most suitable for keeping the quality of tomato fruits.

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Hassku fruit are usually harvested at somewhat immature stage to avoid freezing injury on the tree, and stored for several months to attain ripened quality. The present paper deals with the influences of harvest maturity, degree of perforation of polyethylene package and storage temperature on the quality of stored Hassaku fruit.
The occurrence of rind-oilspot and decay in the fruit harvested at maturity of greenish yellow peel were fewer than that in the fruit harvested at yellow peel. In the former, bitterness of pulp was strong, and sweetness and aroma were poor as compared with the latter even at the end of storage for 150 days.
Organoleptic evaluation after 150 days showed that the fruit stored at 20°C were superior to ones stored at it or sr, but weight loss, incidences of decay and rind-oilspot were severe. The fruit stored at 8°C were poor in taste, and showed severe occurrence of rind-oilspot when transferred to 20°C. The fruit stored constantly at 1°C also showed poor taste, but when transferred to 20°C after 2-3 months their taste was improved and almost no rind-oilspot was found, indicating this temperature sequence may be preferable for prolonged storage. The fruit packaged with polyethylene bag with 16 holes (0.16% perforation) showed less weight loss, decay and rind-oilspot as compared to 100 holes (1% perforation) bag.

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Modified Air System CA (MASCA) is devised as an economical CA storage method. MASCA storage of Shiitake mushroom was carried out at 10°C for 9 days, and its efficiency for extension of shelf life was evaluated from the aspects of visual acceptability and several maturity indicators. 1) The concentration of oxygen and carbon dioxide in the chamber was well controlled between 0-1. 5% and 9-11%, respectively. 2) MASCA reduced the rate of respiration by approximately 1/2. 3) Shiitake stored in air was no longer acceptable after 4 days because of browning, while no quality deterioration was observed during MASCA storage for 9 days. 4) Storage in air increased mannitol and arabitol and decreased trehalose. MASCA showed the similar tendencies to sugar alcohols but did not influence trehalose content. 5) Total free amino acid content was progressively increased during storage in air and MASCA. The rate was more rapid in air than in MASCA. The increase of total amino acid was mainly depending on that of glutamine. 6) The concentration of malic acid was also progressively increased in air and in MASCA.
As a result, MASCA greatly extended the shelf life of Shiitake mushroom.

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The following three kinds of browning tannic acid solution were prepared : Tannic acid dissolved in water (unadjusted=pH 3.8), adjusted to pH 7.0 or 9.0 and turned into brown Tannic acid dissolved into water (unadjusted=pH 3.8), turned into brown by heating at 100°C for 30 or 60 min. Tannic acid dissolved in water (pH 3.8 and pH 7.0), added with amino acids (7 kinds), sugar substances (5 kinds) or organic acids (4 kinds) and then turned into brown by heating at 100°C for 30 minutes.
The chemical properties (reducing power, degrees of browning and pH) and antioxide-tivities of these above solutions were determined.
The results obtained are as follows :
1) The compartment of tannic acid alone showed low pH value as a result of heating.
2) The solution of the compartment of tannic acid alone was alkaline and showed strong coloring and fairly strong reducing power.
3) Strong antioxidativity was showed in the compartment with low pH and 30 minute-heating.
4) In terms of the antioxidativity of amino acid, sugar substance and organic acid compartments, the latter compartment showed a remarkable action.

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