Superoxide anion-scavenging activity (SOSA) of crude pigments obtained from 18 anthocyanin-containing plants was measured. Electron spin resonance (ESR) and colorimetric method using highly water-soluble tetrazolium salt WST-1 (WST-1 method) were used for measuring SOSA. Consequently, crude pigments from purple pods of pea (Pisum sativum L.) and tuber of red potato (Solanum spp.) were potent scavengers with >60% inhibition at a level of 0.1mg/ml. Crude samples extracted from red potato and purple sweet potato (Ipomoea batatas cv. Ayamurasaki) also showed high activity (>70% inhibition). In order to find active components, major anthocyanins were prepared from those plants, and then their SOSA were measured. PS1 derived from P. sativum L. possessed the most potent activity as shown by SOD equivalent activity of 137units/mg. In addition, delphinidin- or cyanidin-based anthocyanins showed relatively high SOSA. SOSA of anthocyanins changed by acylation with caffeic acid. It was also observed that the activity of acylated anthocyanins varied depending on the activity of each corresponding deacylated one.

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About 1% of cattle aponeuroses was extracted after 60min of heating in hot water at 85°C. The collagen subunit chains containing β- and α-chains were not detected in the insoluble fractions of cattle aponeuroses after 60min heating at 80°C by SDS-PAGE analysis. The insoluble fractions were treated with plant thiol proteases such as crude-actinidin, papain, bromelain and ficin at 70°C for 60min under acid conditions, and then the effects of extraction from the treated-cattle aponeuroses were analyzed by measuring the yield of total and extracted-collagen. The percentage of extraction from the cattle aponeuroses treated with crude-actinidin, papain, bromelain or ficin was at a level of 34.7, 11.7, 6.6, and 2.8% yield, respectively (p<0.01). Furthermore, collagen subunit chains were detected in the heated-aponeuroses (85°C, 60min) treated with crude-actinidin at 37°C for 3h in 0.5M acetic acid, but not detected in the un-heated aponeuroses extracted with 0.5M acetic acid at 37°C for 3h.

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Relationship between chewing perception, texture of food and masticatory muscle activities was investigated in children (60 panelists; 4 to 6 years old, average of 5.3 years old) and female young adults (54 panelists; 19 to 23 years old, average of 20.5 years old). The texture of food samples tested was measured by Tensipresser, and the chewing frequency and the sum of the proportion of amplitudes for temporal and masseter muscles were calculated from the electromyograms recorded. The chewing perception was evaluated with questionnaire. The results obtained were as follows. (1) The difference between food samples with respect to chewing perception by young adults was recognized, compared with that by the children. (2) For food samples with higher chewing perception, both children and adults showed higher the sum of the proportion of amplitudes. (3) There were high correlation coefficient between chewing perception and the sum of the proportion of amplitudes in masseter muscle. The tendency was more remarkable in the young adults. (4) The chewing perception in children were correlated with the hardness of food, while that in adults with both the hardness and chewiness of foods. (5) The masticatory muscle activities were considered to depend on the chewiness in the texture of foods.

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Effect of 0-1.0% calcium carbonate, calcium hydroxide, magnesium chloride and magnesium sulfate on gelatinization of 10% nonglutinous rice starch were discussed by measuring of heating DSC curves, X ray diffraction and mechanical properties. A endothermic peak in a higher temperature on heating DSC curve became broad by the addition of calcium carbonate and a single endothermic peak was observed on the DSC curve of nonglutinous rice starch with calcium hydroxide. A endothermic peak in a lower temperature was shifted to higher side by adding magnesium chloride or magnesium sulfate, and a starting temperature of peak in higher temperature of nonglutinous rice starch containing magnesium sulfate was shifted to higher side. X ray diffraction pattern of heated nonglutinous rice starch became a gentle corn-shaped curve by the addition of calcium carbonate, calcium hydroxide, magnesium chloride and magnesium sulfate. Storage modulus of heated nonglutinous rice starch containing calcium hydroxide decreased up to concentration of 0.5% calcium hydroxide and increased at 1.0% calcium hydroxide. Storage modulus did not observe the remarkable change by adding other salts.

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The effects of calcium carbonate (CaCO₃), calcium hydroxide (Ca(OH)₂), magnesium chloride (MgCl₂) and magnesium sulfate (MgSO₄) on structure of 41.2% nonglutinous rice flour dough were investigated by measuring the heating DSC curves and values of rupture properties and by observing the SEM images. In unheated dough containing Ca(OH)₂, the conjunction of starch particles was promoted as compared with those containing CaCO₃, MgCl₂ and MgSO₄ based on the observation by SEM. The water absorption of heated dough decreased by additions of Ca(OH)₂ and MgCl₂ as compared with rice flour dough alone (p<0.05). Rupture stress and rupture strain of unheated nonglutinous rice flour dough increased by adding 1.0% and 1.5%Ca(OH)₂. Rupture stress of heated dough containing MgCl₂ and MgSO₄ increased and that containing Ca(OH)₂ decreased, but that containing CaCO₃ did not change. The effects of soak in ionized water on physical properties of heated dough containing Ca(OH)₂ was smallest and those containing MgCl₂ and MgSO₄ were larger.

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The purpose of this research is to utilize wood vinegar manufactured from drift wood as a food additive as one of the effective utilization methods, removal of formaldehyde and methanol from wood vinegar recovered from drift wood, and smoke flavors and their antioxidant properties have been examined. Extracted wood vinegar from drift wood with benzene fractionated to acidic, phenolic and neutral Fraction using 5%NaHCO₃ and 5%NaOH. Twenty-three main smoke flavors were identified by GC and GC-MS. Each content of formaldehyde and methanol was 5ppm or less in any fraction and the content of organic acids were 0.01% or less in any fraction. Phenolic fraction showed most strong antioxidative activity and DPPH radical scavenging activity. Guaiacol derivatives, 2, 6-dimethoxyphenol derivatives showed strong antioxidative activity and radical scavenging activity. Wood vinegar using drift wood as a row material can be manufactured without consuming forest resources compared with conventional wood vinegar. In additional, the smoke flavors extraction from wood vinegar has possibility for application to food as a safer product than conventional wood vinegar.

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Antimicrobial activity of fatty acid esters was examined on two Bacillus species with different germination rate in a chicken extract. The fatty acid esters with high hydrophobicity had strong antimicrobial activity toward B. cereus that showed high germination rate in the extract. Monoglycerol myristate was the most active toward B. cereus among fatty acid esters tested. On the other hand, monoesters of laurate had strong antimicrobial activity toward B. coagulans that showed low germination rate in the chicken extract. Monoglycerol monolaurate was the most active against B. coagulans among the fatty acid esters tested. The difference in the antimicrobial activity of fatty acid esters on these two Bacillus species seems to be attributed to the difference in the target and mechanism of the antimicrobial action. The antimicrobial activity of sugar esters toward B. coagulans was low as reported by other researchers. It was thought that the interaction between components in the extract and sugar esters decreased the concentration of the active esters in the extract. These results suggest that, to prolong the shelf life of meat extracts, it is important to identify Bacillus strains that cause putrefaction of the extract, and then select the most effective fatty acid ester to inhibit germination and growth of the target strain.

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Proteins of quinoa and roasted-quinoa flours were fractionated and analyzed. The protein content of the flours was 11.7-12.5% (w/w). In quinoa flour, water-soluble protein (albumin) and NaCl-soluble protein (globulin) constituted 28.5% (w/w) and 34.1% (w/w) of total protein, respectively. Amino acid profile of each protein fraction showed a balanced content of essential amino acid for quinoa flour when compared with reference patterns from the World Health Organization. The lysine level of each protein fraction of quinoa flour (4.5-7.0%, w/w) was high, compared with major cereals such as rice and wheat. On the other hand, insoluble protein comprised 54.4% (w/w) of total protein in roasted-quinoa flour. The level of water-soluble and NaCl-soluble proteins decreased in the roasted flour. SDS-polyacrylamide gel electrophoresis revealed that polypeptides of high molecular mass found in each protein fraction of quinoa four were degraded by roast. The lysine level of each protein fraction was decreased by the roast. The amino acid score for each protein from roasted-quinoa flour was lower than that of quinoa flour. Lysine was the first limiting amino acid in all fractions of proteins from the roasted flour. These results showed that quinoa could be used as a nutrient substitute for the cereals, but the balance of essential amino acid in roasted quinoa was lowered resulting from the decrease of lysine level.

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Potent antioxidant activity was observed in methanol extracts of avocado (Persea americana Mill.) seeds. The extracts were fractionated by successive silica gel chromatography using chloroform-methanol (1:1) and chloroform-methanol-acetic acid (7:3:1) as eluents, and was followed by reversed phase preparative HPLC (15% acetonitrile containing 0.1% trifluoroacetic acid), which gave (+)-catechin and (-)-epicatechin as major active components. Results of AMVN-induced methyl linolate peroxidation assays showed that lipid peroxidation of the isolates at concentration of 0.1mM (21% and 17%, respectively) were lower than that of caffeic acid at the same concentration.

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