Changes in Total Ascorbic acid (T-AsA) content and DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activities during storage of persimmon leaf tea of ‘Saijo’ subjected to steam and/or roast treatments ware investigated using persimmon young leaves. The obtained results were as follows : (1) The steaming treatment for 5 minutes without roasting provided the highest T-AsA content. (2) In non-steaming treatment, T-AsA was remained only by roasting treatment before storage. (3) In the steaming treatment for 5 minutes, the same level of T-AsA content was maintained by the roasting treatments before and after storage. (4) T-AsA and other polyphenols may affect the DPPH radical scavenging activities of persimmon leaf tea. (5) It was thus concluded that the suitable steaming and roasting treatments could produce persimmon leaf tea containing higher T-AsA content and DPPH radical scavenging activities.

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Pepsin-solubilized collagen was prepared from scallop mantle. The scallop mantle pepsin solubilized collagen (SMPC) was subjected to analyses of amino acid composition, digestive pattern by protease, electron microscopic view of collagen fibers, and moisture absorption to evaluate its characteristics in comparison with bovine skin type I and bovine placental type V collagens. The amino acid composition of SMPC coincided with that of bovine type V collagen. The SDS-PAGE analysis showed that two α-chains were similar in molecular weight to those of bovine placental type V collagen. However, SMPC was more susceptible than bovine placental type V collagen to Staphylococcus aureus V8 protease digestion. The diameter of the SMPC gel fibril was about half of the bovine type I collagen gel fibril. Gel formation ability of the bovine type I collagen was higher than that of SMPC. SMPC showed a higher moisture absorption isotherm under high humidity than bovine skin type I collagen. Electron microscopic view of SMPC showed in part a sponge-like structure.

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It was investigated whether methylcellulose microcapsules containing l-glutamine were able to be prepared by using coalescence between two kinds of droplets in W/O emulsion or not. Methylcellulose as the shell material was dissolved in the one aqueous droplets and the tannic acid as the gelation agent for methylcellulose was dissolved in the other aqueous droplets. It was found that methylcellulose microcapsules were able to be prepared by coalescence between the two kinds of droplets. The mean microcapsule diameter and the content rate of l-glutamine were found to increase with the concentration of methylcellulose. Moreover, it was found that microcapsules were not destroyed in the water phase and l-glutamine was released through the ungelated part of the microcapsule shell.

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We extracted lipophilic components from four vinegar varieties (7 samples), examined their characteristics by silica gel thin-layer chromatography, and analyzed component fatty acids as ρ-nitrophenacyl derivatives using reversed phase HPLC. The amount of chloroform-methanol extracts (1 to 8mg/100ml vinegar) was highest in rice vinegar (brown rice), followed by rice vinegar (polished rice), cider vinegar (apple juice), and grain vinegar (wheat, sake lees, polished rice, corn, and alcohol). The primary lipid classes from raw materials for vinegar were hardly found in these lipophilic components. Nine fatty acids with carbon numbers from 16 to 22 were recognized ; palmitic acid (32% to 43%), stearic acid (8% to 18%), oleic acid (16% to 36%), and linoleic acid (5% to 16%) being predominant. Rice and grain vinegars were found to have similar fatty acid composition. The total fatty acid concentrations in vinegars ranged from 58 to 194 nmol/100 ml, having individual characteristic fatty acid profiles. Palmitoleic acid, probably derived from yeast, scarcely differed among the vinegar samples in its content. Cider vinegar from U.S.A. was shown to contain much more palmitic and oleic acids than those of all domestic cider vinegars.

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In order to clarify the effect of deep sea water on the texture of Japanese noodles (Udon), two kinds of Udon with or without deep sea water were prepared (DSW : deep sea water was added to flour in the ratio 39 : 100, Control : 2.5% NaCl solution was used instead of deep sea water). Physical properties and microstructure of both noodles were compared after boiling for 12 min. Both tensile strength and elongation of DSW were significantly higher than those of Control. This result suggested that an addition of deep sea water positively contributes to the textural properties of Udon. A natural scanning electron micrographic observation of DSW showed finer network than that of Control. Udon prepared with 2.5% NaCl solution containing 0.04% Ca and 0.04% K showed almost same value in tensile strength and elongation as DSW, suggesting that Ca and K play a major role in the effect of deep sea water.

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Pressurized liquid extraction (PLE) was applied to extract quercetin-3,4'-diglucoside (Q-3,4'-diGlc) and quercetin-4'-glucoside (Q-4'-Glc) in onion for labor saving of extraction process. The experimental extraction parameters such as solvent composition, temperature, static time, and static cycle have been investigated. As a result, the optimum conditions were selected as follows : solvent composition ; 80% ethanol solution, temperature ; 40°C, static time ; 5 min, and static cycle ; 4. Once the optimum conditions were established, the extracts were prepared from 13 onion cultivars harvested in Saga, Nagasaki, Hyogo and Hokkaido prefecture. The content of quercetins in the extract was determined by HPLC. The total contents of Q-3,4'-diGlc and Q-4'-Glc varied according to the cultivar, ranging from 31.7 to 108.3 μmol/100 g-FW. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity increased with the increase of the total contents of Q-3,4'-diGlc and Q-4'-Glc, and the correlation coefficient between then was 0.803. The tendency was observed that the content of Q-3,4'-diGlc was larger than that of Q-4'-Glc in onion harvested in Kyushu region, and vice versa in Hokkaido region.

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On the dependence of frequency for viscoelasticity, soy protein dispersion showed structural viscosity. Soy protein dispersion at pH 6.7 and pH 9.8 showed weaker conformation of protein molecules for shear than that at pH 12.0. It assumed that the weak conformation of soy protein molecules at pH 6.7 and pH 9.8 was due to the grobular stage without attraction among molecules. Based on the relationship between protein concentration and log G' and log η', protein dispersion at pH 6.7 showed the curve with upper salience, on the other hand, that at pH 12.0 showed the curve with lower salience. η'/G' ratio showed the peak at about pH 9.5, and showed that the unholding of protein molecules was in maximum in this pH. η'/G' ratio showed about 1.4 (ω=0.1 Hz) at pH 12.0. In summary, for good spinning of soy protein dispersion, it was suggested that the η'/G' ratio was about 1.4 (ω=0.1 Hz), and the curve need to be lower salience in the relationships between protein concentration and log G' and log η'.

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