The TBA value, an index to the degree of lipid peroxidation, and hydrogen peroxide contents of water convolvulus increased prior to the onset of chilling injury and decreased when severe symptoms appeared. The NAD⁺/NADH ratio was higher at VC than at 20°C during storage. The NADP+/NADPH ratio decreased in both storage conditions. Energy charge at 20°C storage was kept at high level state, but it decreased simultaneously with the appearance of chilling injury at 1°C. Polyphenoloxidase (PPO), ascorbate (AsA) peroxidase and catalase activities also increased before the onset of chilling injury. The results of the present study suggest that under low NAD⁺/NADH ratio, lipid peroxide, hydrogen peroxide relate to the development of chilling injury in water convolvulus.

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An investigation of the concentration of total ferulic acid (TFA) and free ferulic acid (FFA) in 23 mugi miso (barley-koji miso) and 10 kome miso (rice-koji miso) was performed using high performance liquid chromatograph (HPLC).Mugi miso and kome misocontained 34.8-163.1 (mean 66.2), μg/g and 13.9-33.2 (mean 25.6), μg/g of TFA and 1.4-29.2 (mean 10.7), μg/g and 1.5-12.7 (mean 6.0), μg/g of FFA, respectively. With proliferation ofmugi koji (barley-koji), the amounts of TFA were decreased from 350μg/g to 198ug/g, however, FFA were increased and reached a maximum (80μg/g) after 30 h of culture. The radical scavenging activity of themugi kojiextract (100μM ascorbic acid) was significantly higher than that of non-inoculated barley extract (25μM) and the longer barleymugi kojicultivated, the period cultivatingmugi kojiwas, the higher the scavenging activity became. The radical scavenging efficacy of ethanolic extract ofmugi kojiseemed to be correlated with the amounts of ferulic acid and the other phenolic compounds.

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Broccoli (Brassica oleracea L.) with or without leaf stalks was stored to determine the effects of leaf stalks on quality of florets. The broccoli heads were harvested at early summer and autumn and stored at 3°C. Chlorophyll (Chl) a content in early summer-harvested broccoli with or without leaf stalks decreased gradually during storage, while that in autumn-harvested one hardly changed. L-Ascorbic acid content in broccoli with or without leaf stalks also decreased gradually during storage. In contrast to these changes, sucrose content in broccoli without leaf stalks decreased during storage, whereas the attached leaf stalks definitely reduced the decrease in both early summer and autumn harvests. In fructose content, the attached leaf stalks also reduced the decline a little in early summer harvest. Thus, the broccoli with leaf stalks is hardly affected the decrease of Chl and ascorbic acid, but effectively reduced the decrease of sugars. We discussed the effect of attached leaf stalks on the quality maintenance in stored broccoli.

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The influence of storage temperature on freshness, ascorbic acid content, respiration rate, ion leakage from leaf tissue discs and morphological changes of malabar spinach (Basella alba L.) were investigated. At 25°C storage, yellowing of the leaves was mainly responsible for the quality deterioration and lost 50-60% in ascorbic acid content after 4-6 days. Those stored at 0 and 5°C, however, were still green and lost 26-36% after 12-14 days. Lower temperatures were effective in decreasing the yellowing, ascorbic acid loss and the respiration rate. However, upon transfer to 25°C, the CO₂production increased rapidly and significantly higher increases were observed from those stored at 0 and 5°C than those stored at 10 or 15°C. This respiratory stimulation was positively correlated with the increase in the rate of ion leakage at 0 and 5°C. Chilling injury was observed in storage at 0 or 5°C and was manifested as pitting and softening (loss of turgidity) of leaves. Stomata were the only openings on the epidermis of the leaves and frequencies were greater on the abaxial surface than on the adaxial surface. Cracking of the tissue near the stomata and exudates outside the stomata were observed after 12-14 days of storage at 0 and 5°C.

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The removal of water-insoluble protein existing in Okara by chemical and enzymatic treatment had done in order to obtain dietary fiber (DF) of high purity, and DF were observed through scanning electron microscope (SEM). The combining chemical and enzymatic treatments were highly effective in extracting DF of high purity from Okara. The following treatments were performed : Okara was treated chemically at pH10.0, and then by enzymes, protease (method-1), and Okara was treated chemically at pH10.0, followed by enzymes, pectinase first and protease (method-2). Both Okaras were DF of high purity. Okara obtained by method-1 contained 96.3% TDF, 3.9% protein, and that by method-2 contained 98.6% TDF, 1.4% protein. It was observed by SEM that particles of Okara obtained by method-2 was much the same in form as cellulose powder on the market. On the other hand, Okara by method-1 had a large surface area and was porous. Consequently, chemical and enzymatic treatment Okara (CETO) obtained in this study was considered to be used in a similar way to cellulose on the market, and also to be used for adsorbent substances by taking advantage of its porosity.

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