Enterohemorrhagic Escherichia coliO157 : H7 (Ex-1064) were inoculated into various foods such as minced meat, milk, fruit juice, and other commercial foods. During the storage at-20°C for 15 days, the survival number of inoculum was periodically assessed. Furthermore, the influence of foods thawing process on the residual number of inoculated E. coli O157 : H7 was tested. (1) The foods tested were roughly classified into three groups as follows by the behaviors of residues. (1) Group A-1 foods : The survival number remained constant during 15 days : minced meats (beef, pork, chicken, hamburger meat and fish). (2) Group A-2 foods : The survival number gradually decreased in 15 days : milk, bouillon, corn potage, white sauce, mashed potato, boiled fish paste (kamaboko), bean curd, fried bean curd (atuage), omelet and boiled rice. (3) Group B foods : The number of inoculum decreased rapidly and disappeared within one day : fruit juice and acidic sauce (apple juice, orange juice, soy sauce, Worcestershire sauce, demiglace sauce, French dressing, Italian dressing, and Thousand Island dressing). (2) For the studies of the influence of food thawing process on the residual number of E. coli O157 : H7, inoculations were carried out into both Group A-1 foods, minced beef, and also Group A-2 foods such as milk and bouillon. However, there was no difference in the number of residues among the thawing process in the tap water, in the refrigerator, and at room temperature.

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Distribution of the chain lengths of amylopectin contained in the starch of Akamai, Haenuki and Sasanishiki, and the taste characteristics of the three varieties of rice were examined. The distribution of amylopectin chain lengths indicated the following characteristics : The values of Fr. III/Fr. II for Akamai was 3.6, for Haenuki, 2.9 and for Sasanishiki, 3.4. Among longer amylopectin chains, 19.0mol% of chains in Haenuki had an average length of 60 or more, while the greatest proportions of chains in Akamai and Sasanishiki averaged 30-40. Among shorter amylopectin chains, on the other hand, more chains had lengths of 10-20 for Akamai, Haenuki and Sasanishiki. The average chain lengths of the sum of Fr. II and Fr. III was 24.5 in Akamai, 39.5 in Haenuki and 19.9 in Sasanishiki. In a sensory evaluation, Akamai tended to have lower scores compared to Haenuki or Sasanishiki.

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Previously, we reported that KS-F2 (non-dialyzable fraction of hot water extracts from skin of Aloe arborescensMiller) and AS-F2 (non-dialyzable fraction of hot water extracts from skin of Aloe africanaMiller) with de-protein showed a high mitogenic activity towards cells of mice (_??_) (C3HeN/C3HeJ). The water-soluble polysaccharides obtained were fractionated and purified by ion-exchange chromatography on a DEAE-Toyopearl 650M column. The chemical structres of K-1, the mitogenic activity component of KS-F2 and A-1, those of AS-F2, were analyzed. Arabinose and galactose were contained in both K-1 and A-1. The molar ratio of arabinose to galactose was 1 : 1 in K-1, and 1 : 2 in A-1 before reduction and 1 : 3 in K-1, and 1 : 3 in A-1 after reduction. The ratio of galactose increased both K-1 and A-1. Consequently, uronic acid seemed to be galacturonic acid. The ratio of neutral sugar to uronic acid contents in K-1 and A-1 was about 1 : 1 and 5.6 : 1, respectively. K-1 and A-1 were found as gel-filtration fractions with a high molecular weight of approximately 1, 700, 000 and 1, 750, 000, respectively. The main components in K-1 were found to be arabinose and galactose based on their [α] _D value of +127 (H₂O) and a peak of 890 in IR ν max cm^-1. A-1 also showed arabinose and galactose based on their [α] _D value of-33 (H₂O) and a peak of 830 in IR ν max cm^-1. Therefore, K-1 seemed to be a β-glucosidic bond, and A-i was close to a β-glucosidic bond. After the controlled hydrolysis of K-1 and A-1, an investigation of the bond form was performed using thin layered chromatography. It was suggested that arabinose and uronic acid were located on the outside and that arabinose and galactose constituted the core of the K-1 and A-1 structures. Using GC/MS, the methylation analysis gave 1, 4-di-O-acetyl-2, 3, 5-tri-O-methyl arabitol, 1, 5-di-O-acetyl-2, 3, 4, 6-tetra-O-methyl galactitol, 1, 3, 5-tri-O-acetyl-2, 4-di-O-methyl arabitol, 1, 3, 5-tri-O-acetyl-2, 4, 6-tri-O-methyl galactitol, 1, 5, 6-tri-O-acetyl-2, 3, 4-tri-O-methyl galactitol and 1, 2, 5, 6-tetra-O-acetyl-3, 4-di-O-methyl galactitol in the molar ratios of 4.3 : 3.4:1.0:3.1:1.9:6.0 from the K-1 core, and 2.4:2.5:1.0:3.8:1.1:2.8 from the A-1 core, respectively.

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The effect of storage at 0°C and 10°C on physical and biochemical parameters of 'Danshaku' tubers was monitored to provide baseline information on this cultivar's storage behavior. Sugar and starch level, weight loss, firmness, specific gravity, tissue color, fatty acid composition of phospholipicls, sprouting and respiration rate, starch content, particle size, and pasting properties were monitored. Sugar accumulation occurred in tubers stored at 0°C, while minimal sugar accumulation and severe sprouting and weight loss was observed for tubers at 10°C. Tubers stored at 10°C were consistently softer due to weight loss. No significant changes were observed in tissue color between storage treatments. Double bond index of tissue increased after 30 days at 0°C, indicating an adjustment to cold stress to increase tolerance. Sprouting occurred earlier in tubers stored at 10°C ; final respiration was also higher compared to tubers stored at 0°C. Starch content and particle size decreased during storage ; however, a greater reduction was observed at 0°C storage.

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The pink discoloration occurring in canned sand pears is considered a sign of poor quality in this product. Factors contributing to pink discoloration were investigated. The major precursor of pink discoloration in canned sand pears existed in the insoluble solids of the sand pear. This precursor belonged to the flavonoids which became a pink color after being heated in acidic conditions. The pink compound was a cyanidin which was the only aglycone component in the canned sand pear. The addition of citric acid at 0.15 % was sufficient to lower the pH below 4.6. The use of syrup at the same degree Brix and the same sugar profile of the fruit flesh resulted in less pink discoloration than those with heavy syrup.

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Banana (Musa spp.) is an important economic fruit crop in the tropics. Like other tropical fruits, banana fruits often develop physiological disorders upon ripening. Senescent spotting is widely distributed in banana fruits among other physiological disorders. Senescent spotting develops during the latter phase of ripening when the banana fruits are most desired. Bananas in AA Group have the most serious senescent spotting. Preharvest sprays of carbendazim and prochloraz solutions to banana bunches with and without bagging and postharvest dipping in benomyl and prochloraz solutions did not reduce the severity of senescent spotting. Modified atmospheres, surface coating, low temperature and heat treatment of banana fruits attaining yellow colour in the peel with green tip reduced the severity of senescent spotting considerably, while ripening processes and eating quality of the banana fruits were not altered.

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