Gelatinization thermal properties of various starches were examined using rapid visco-analysis (RVA) and dynamic viscoelasticity measurement in the gel matrix (GDVM). These properties were compared with thermal properties of gelatinization endotherm (GE) obtained using differential scanning calorimetry. Onset temperature of RVA viscosity (R_o) for root, glutinous grain and bean starches was higher than and correlated with peak temperature of GE (T_p). R_o for nonglutinous grain starches (NS), swelling power of which was relatively low, was considerably higher than and slightly correlated with T_p. Temperature, for which the maximum increase of RVA viscosity was obtained, was rather higher than and closely correlated with Tp in starches except for NS. Onset temperature of G' in GDVM (G_o) under 10% starch concentration was level with and correlated with T_p, and G_o at 33% approached and correlated with initiation temperature of GE (T_i). Go lowered when starch concentration increased, and was under T_i for highly concentrated starch samples, due to detecting viscoelasticity change by moisture absorption of raw starches. The temperature, for which the maximum increase of G' was obtained, was just higher than and correlated with T_p in all starches, irrespective of starch concentration. Peak temperatures of G' and RVA viscosity were higher than conclusion temperature of GE and weakly correlated with thermal properties of GE.

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Viscoelasticity behavior of starches originated from various botanical sources during gelatinization was examined using the gel-dispersed dynamic viscoelasticity measurement (GDVM), which measures the viscoelasticity behavior of starches in a gel matrix during gelatinization. These results were compared with viscosity characteristics obtained from rapid visco-analysis (RVA). Viscoelasticity characteristics of starches were classified into root, glutinous grain, nonglutinous grain, and bean starches, using viscoelasticity modules (G', G", tanδ) obtained by GDVM at 6.6%, 10% and 33% starch concentration. It was explained using the revised Kerner's equation that GDVM viscoelasticity characteristics were reflected by the viscoelasticity of starch granules but that of xanthan-gum solutions. Viscoelasticity characteristics of starches except nonglutinous grain starches indicated mechanical properties of starch granules even if obtained at considerably low starch concentration. However, those characteristics of nonglutinous grain starches, swelling powers of which are relatively low, did not indicate the same properties when obtained at below 20% starch concentration. The starches were classified with viscosity characteristics of RVA as same as by GDVM. G' and G" at 6.6% starch concentration and G' at 10% were significantly correlated with all viscosity characteristics of RVA, and had the maximum correlation with final viscosity.

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A placebo-control double-blind study of long-term intake of glucosamine hydrochloride (1500mg/day for 6 weeks) was conducted in 32 women who usually tend to have dry and rough skin. The following findings were obtained: (1) Examination by dermatologists indicated that glucosamine hydrochloride significantly improved dryness of the skin, easiness to apply make-up, and exfoliation. (2) Determination of the moisture content in the skin revealed that glucosamine hydrochloride increased the moisture content in the skin. (3) Microscopic skin surface analysis showed that glucosamine hydrochloride improved smoothness and scaliness of the skin. These findings suggested that long-term intake of glucosamine hydrochloride is effective in improving moisture content and smoothness of the skin.

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Gly m Bd 28K, one of the major soybean allergens, was analyzed in six leading varieties in Japan by immunoblot analysis using monoclonal antibody specific to Gly m Bd 28K. Among these, five varieties, which account for nearly half of the total soybean acreage in Japan lacked. Gly m Bd 28K. Since each of the five soybeans belongs to much different maturity groups, a gene or genes of lacking Gly m Bd 28K may exist commonly in Japanese domestic varieties. Fukuyutaka-QT2 line, which has been bred to lack α-, α' and β-subunits of β-conglycinin, lacks Gly m Bd 28K, same as its recurrent parent Fukuyutaka. Both Gly m Bd 28K and α-subunit of β-conglycinin have secondarily highest reactivity with the sera of soybean-allergic patients, and β-subunit of β-conglycinin is also one of the major soybean allergens which reacts with 10% of the sera. Therefore, Fukuyutaka-QT2 line would be a promising source for developing a less allergic soybean variety.

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Irwin mango fruits cultured in a plastic house were harvested on the 18th of August 1997 (the time of full bloom of the trees was late in May), and were used in the experiment. Fruit storage trials were undertaken at 7-25°C. Hunter's _L values of the fruit skin were almost constant with storage at any temperature, and for any time. However, Hunter's L values of the flesh decreased with time of storage. Hunter's a and b values of the skin and flesh increased with storage at 15°C for 18 days or 25°C for 4 days and then at 7°Cfor 1-3 weeks. On the other hand, the flesh firmness on the equatorial portion decreased strikingly with increased storage, and the definite difference between the seed and skin sides in fresh fruits nearly disappeared. The respiratory rate in fruits at the early stage of storage was higher than that of the initial fruit, but the rate declined as the storage time progressed. There was a distinct increase in total soluble solids content in all fruits. The sucrose and fructose levels increased relatively in all fruits with storage, as compared with the initial one. On the other hand, the polysaccharides content, particularly starch decreased dramatically. Furthermore, a decreasing trend of citric acid content was observed, while in malic acid is increasing. The results suggested that the quality of fruits stored under the various storage conditions is almost the same except the fruits stored at 15°C·18d+7°C·21d, and that the preservation of fruits under the conditions mentioned above may be possible within approximately one month. Also, it may be consider that there are similarities in the changes in physical and chemical properties during the fruit storage without considering distinctions of cultivar, condition or environment of cultivation.

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After the fermentation of cow milk by using lactic acid bacteria, rennet was added, and then 7S and 11S globulins were added to it. The curd was formed at 30°C for 12 hours, under static conditions. Effects of various reagents (NaCl, NaSCN, 2-mercaptoethanol and propylene glycol), which affect forces involved in protein-protein interactions, on formation and solubility of the curd were studied. Among these reagent, NaSCN was the most effective for the inhibition and the solubilization of cow milk curd containing 7S and 11S globulins. No distinctive feature was observed in the compositions of proteins solubilized from the curd containing 7S and 11S globulins by those reagents. These results suggested that hydrophobic and electrostatic interactions were more important for the formation and the maintenance of the curd containing 7S and 11S globulins, than disulfide and hydrogen bonds, and that all the constituent subunits of both globulins contribute evenly to the curd.

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A mirin-like sweetener for seasoning (potato mirin) was prepared from potato produced in Hokkaido. Peeled and crushed potato (200g) after cooked at 121°C for 30min, rice koji (40g) and syocyu (100g) containing 35% (v/v)-ethanol were mixed and incubated at 30°C for 60 days. Effect of the addition of α-amylase (Amylase AD [AMANO] 1) and neutral protease (Denatyme AP) was examined. There were little differences on a yield, total sugar (as glucose) and ethanol content between potato mirin prepared without and with 0.03%, 0.07% and 0.15% (w/w) of the enzymes. But the nitrogen content of the product increased of the remarkably when 0.15% (w/w) of the enzymes was added, indicating that 0.15% enzyme concentration was most suitable. In potato mirin prepared by the addition of 0.15% enzymes, yield ratio, total sugar (as glucose), ethanol and total nitrogen were 72% (w/w), 22.4 (w/v), 8.5 (w/v) and 0.27% (w/v), respectively. Its major sugar components were glucose 18.3% (w/v) and isomaltose 2.3% (w/v). And the total free amino acid content in this potato and commercial mirin was 0.92% (w/v) and 0.23% (w/v), respectively. Recovery ratios of glucose and total nitrogen weight were about 70% and 65%, respectively. For mass balance of potato mirin preparation, when 100g of fresh potato was used, peeled and crushed potato, total materials for incubation and recovered potato mirin were 87.4g, 149.0g and 107.3g, respectively.

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We examined the effect of acidic electrolyzed water (AcEW), NaOCl solution (150ppm), and tap water on the quality of fresh cut vegetables. The vegetable quality tested in this study was the color tone of the appearance, the total chlorophyll content, the β-carotene content, and the ascorbic acid content. The appearance of the cut or non-cut vegetable was not changed by the 10 min soaking in AcEW. The total chlorophyll content in the cut cabbage and the cut lettuce soaked in AcEW for 10min was decreased by 10-20%. The β-carotene content in the carrot soaked in AcEW for 10min was decreased by about 30%. However, the reaction mechanism of these decreasing of pigment content is not clear. On the other hand, the ascorbic acid content in the cut cabbage, cut lettuce and cut cucumber treated with AcEW for 10min was decreased by 20%, 15% and 35%, respectively. These results were also shown in the treatment with NaOCl solution and tap water. Thus, the loss in quality of the cut vegetable treated with AcEW was equivalent with NaOCl and tap water. Therefore, it was found out that AcEW did not affect the quality of cut vegetables.

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A fungus was grown in the wetted defatted sesame seed at room temperature. In the visual observation, the colony of the fungus was white and wooly, and in the microscopic observation, its sporangiophore was colorless and branched. Based on these observations, we identified the fungus as Absidia corymbifera. The amount of sesaminol triglucoside included in the defatted sesame seed decreased largely by the incubation of this fungus for 84h and then, sesaminol that has antioxidative activity was produced largely. Amounts of sesamin and sesamolin included in the defatted sesame seed did not change by the incubation for 24h. As the results, we could clarify sesaminol triglucoside was converted into sesaminol using the fungal metabolism by Absidia corymbifera.

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The dependence of a flow characteristic of soup made from mash potato on a dynamic characteristic of a straining process of potatoes was examined. A skilled person controlled the damage of potato cell by using a wooden spatula at a big angle not to rub it against a sieve with a necessary, minimum resultant force compared with an unskilled person, and conducted a straining operation by which the outflow of starch from potato cells was prevented. The soup made from the mash potato strained by a skilled person had significantly small apparant viscosity and yield stress. On a sensory evaluation stickiness was weak and overall texture was desirable. It was concluded that potato soup made by a skilled person was finished up desirable to cold potato soup.

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