Fresh-cut green bananas (non-C₂H₄ treated) were prepared in the following four styles : 7cm-long and 1cm-thick sections cut longitudinally (LCS), 1cm-thick crosswise sections cut transversely (0 CCS), and cut obtusely to the transverse at 30° (30 CCS) or 60° (60 CCS). Each section packed in polyethylene bags was stored at 20°C. I. The cut surface area and weight of LCS were the largest, followed by 60 CCS, 30 CCS, and 0 CCS, but no major differences were found in the ratio of the surface area/weight among sections. 2. The color in the peel of all sections changed during 6 days storage. The LCS began to yellow most rapidly, followed by 30 CCS, 60 CCS, and 0 CCS. The concentrations of C₂H₄ and CO₂ in polyethylene (PE) bags were the highest with LSC and those of the CCSs increased with increasing the obtuse angles until day 3. 3. The respiration rate (CO₂ production) of the intact green bananas increased slowly during 7 days storage. The respiration rate of LCS increased rapidly, and that of CCSs increased until day 4, the increase being greater in 60 CCS. Ethylene production was not detectable from intact green bananas during 6 days storage. The LCS showed the increase of C₂H₄ production and the peak of production was on day 2. The 60 CCS showed the peak on day 3 and the C₂H₄ production rate of the 30 and 0 CCS reached the peak on day 5. The peak of 30 CCS was higher than that of 0 CCS. 4. There were significant linear increase in sugar content and decrease in starch content of pulp in all sections during 6 days storage. The LCS showed these changes most rapidly followed by 60 CCS, 30 CCS, and 0 CCS. 5. It appears that the cutting of green banana fruits induces the activation of physiological and chemical changes, and these changes are associated with cutting direction.

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The appearance of turbidity in liquid part decides the shelf life of “Asazuke”. Then, the relationship of their speed to materials factors was studied. They were different from other kinds of vegetables. Especially, cucumber's liquid remained clear, compared to other vegetable's liquids. Grafting technique had no effect on it. Addition of cucumber to Chinese cabbage' had no effect on the turbidity's speed in their liquid. Potassium ion concentration in the liquid increased during storage after processing. The contents of total sugar and malic acid also increased, but thereafter decreased. Their degree of change differed depending on the type of vegetable. The content of total amino acid indicated the same change in cabbage, cucumber and eggplant, but the biggest change was in cabbage “Asazuke”. Counts of total, gram negative bacteria, eumycetes and lactic acid bacteria, which were attached on the surface of cucumber, eggplant and radish at harvest time and after washing, was not very high, compared to the others.

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We investigated the structure and mechanism of antioxidative substance (Ala) that is extracted and purified from freeze-dried meat treated with steaming for 60 minutes. The infrared absorption spectrum of the antioxidative substance (Ala) was studied to recognize absorption at 3475^-1cm due to hydroxide group, at 1628cm^-1 due to carboxyl group, at 3350 and 1288cm^-1 due to peptide bonding, as well as at 1395cm^-1 due to imidazole group in hystidine residue. The compositions of sugar and amino acid were studied by thin layer chromatography. As a result, glucose was detected in sugar, and hystidine and β-alanine were detected in amino acid. To elucidate the antioxidative mechanism, the antioxidative substance did not change Vmax and only increased the Km value by Lineweaver-Burk's plot. Antioxidative substance which was the radical scavenging property to supply hydrogen was not recognized and antioxidative substance showed a high absorption of oxygen. The elimination action of superoxide was recognized in the antioxidative substance.
The antioxidative substance markedly inhibited the promotion of lipid oxidation by Fe²⁺ and Cu²⁺.

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Effects of coating with three different kinds of sucrose fatty acid esters-namely, sucrose lauric acid esters (SLE), sucrose palmitic esters (SPE), and sucrose stearic acid esters (SSE), were studied on the ripening of Cavendish bananas. The bananas were coated with 0.5% sucrose fatty acid esters solution and stored at 20°C. The use of sucrose fatty acid ester coating delayed banana ripening. The onset of ripening was first observed in non-coated bananas, then subsequent in SE, SLE and SPE-coated bananas. Initiation of respiratory climacteric and ethylene production was delayed by sucrose fatty acid esters coating. The longest storage period of bananas was 52 days which was coated with SPE and found to be statistically significant. The total and the reducing sugar of SLE-coated bananas were observed to be higher. A scanning electron microscopy study showed that the stomatal apertures of bananas were partially blocked by fragments of the coating treatment, which might form a physical barrier of gaseous diffusion with the external atmosphere.

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Respiration rate and ethylene (C₂H₄) production in harvested broccoli (Brassica oleracea L.) were examined. Effect of packaging with films of different O₂ permeability on quality maintenance was studied. (1) The higher the storage-temperature, the higher the respiration rate was observed. Seven days after harvest, the respiration rate decreased under 50% of that at the time of harvest. The production of C₂H₄ was slightly under 10°C and increased remarkably over 10°C. (2) At the stage that the flower buds of broccoli became soft, the respiration rate increased. However, the effect of the stage of broccoli on respiration rate was less than on C₂H₄ production, C₂H₄ production increased remarkably at the stage that the flower buds became slightly soft. (3) The respiration rate of early cultivars were higher than that of medium and late cultivars. (4) The difference of effect among films on maintaining freshness was slightly at 0°C and 5°C storages, a high fresh score was maintained for 2 weeks at 0°C and 1 week at 5t in almost all films. (5) At 10°C storage, a high fresh score was maintained for 4 days in almost all films. And a high fresh score was maintained for 7 days in films with low gas permeability. At 20°C storage, a high fresh score was maintained for 4 days in films with low gas permeability. However, in films with low gas permeability an unfavorable off-flavor occurred. (6) These results indicate that at 10°C storage, quality is high in films with O₂ permeability of about 4000ml/m² · day · atm (15°C). However, it is suggested that the use of films with O₂ permeability of over 10000ml/m² · day · atm (15°C) is practical, when the temperature of broccoli is over 20°C.

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For the preservation of “Hakusai-Asazuke” (a salted Chinese cabbage) during 10 days under 10°C, application of potassium sorbate and sodium acetate was investigated. Debaryomyces hansenii was identified in the deteriorated pickle. The minimum inhibitory concentrations of potassium sorbate to this yeast were 0.06% at pH5.0 and 0.14% at pH5.5, respectively. These concentrations were lowered 0.04% at pH5.0 and 0.12% at pH5.5 in the case of existence of 2% sodium acetate, which did not affect the yeast growth individually. The growth of Gram-negative bacteria isolated from the pickle was inhibited by 0.2% of sodium acetate at pH5.0. Also, the growth of lactic acid bacteria was inhibited by 2% sodium acetate. By adding at the same time with 0.1% of potassium sorbate and 0.4% of sodium acetate at ph5.0, “Hakusai-Asazuke” were preserved from deterioration of microorganisms during 15 days under 10°C.

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