Various plastic films coated and baked on aluminum foil were individually immersed in lemon-flavored aqueous solution in sealed glass jars.Every solution was pasteurized and stored at 25°C for one week. The volatiles in the lemon flavor solution were concentrated with chromosorb 106 and the subsequent ether elution.Then the volatiles were quantitatively analyzed by GC-MS.Cluster analysis and principal component analysis were applied for the obtained 17 GC peak area data.As the result of cluster analysis, the films were roughly classified into two groups corresponding to their resin types (Waterborne or Solventborne). As the result of principal component analysis, the films were roughly classified corresponding to their resin types and resin compositions.Total amount of flavor compounds contributed to the first principal component and amount of terpinen-4-ol or α-terpineol known as off-flavor compounds of Satsuma Mandarin Juice contributed to the second principal component.

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The effect of ozone exposure (concentration: 0, 0.03, 0.1 and 0.3ppm) during cultivation of Nameko mushroom (Pholiota nameko) was investigated on the weight and chemical composition (water, protein, lipid, carbohydrate and ash as major constituents; Ca, Fe, Na, K and Zn as minerals; and thiamin, riboflavin and ascorbic acid as vitamins) on the dry matter basis of fruit bodies i.e., pileus, stipe and whole. As to the ozone treatment, a significant increase was observed in the water, lipid, carbohydrate, thiamin and ascorbic acid contents in pileus, in the water, ascorbic acid contents in stipe and in the water, lipid and ascorbic acid contents in whole. On the other hand, a significant decrease was observed in weight and protein, ash, Fe, Na, K and Zn contents in pileus, in weight and ash, K and Zn contents in stipe and in weight and ash, Na, K and Zn contents in whole. The pileus, as compared with the stipe, had higher amounts of major constituents except carbohydrate and also higher Fe, Na, Zn, thiamin and riboflavin contents on 0ppm ozone culture (control).

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The relation between the content of 6-methoxymellein (6-MM) and the tastes of winter carrot roots harvested in the middle of February was investigated. Sensory evaluation indicated the threshold values of 6-MM for off-flavor and bitter taste were 60 and l00μg/ml, respectively. A high-performance liquid chromatography (HPLC) method with an ODS column was newly developed for the rapid determination of 6-MM, where the component was separated clearly from other components in the carrot extract with a mixture of 60% MeOH/H₂O. Although 6-MM was detected in almost all of the carrots tested, the 6-MM content was lower than the threshold for bitterness. The observation indicated that 6-MM gave little effect on a taste of winter carrot roots freshly harvested.

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Headspace gases of 36 compounds having various functional groups were individually injected into a test box where eight semiconductor gas sensors were installed. Relative sensor responses to each compound were correlated to the organicity (the quality or state of being organic) and inorganicity (the quality or state of being inorganic) values of the compound. The sensor responses were classified into six groups by cluster analysis. Compounds belonging to each cluster showed similarity in their organicity and inorganicity.

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Specific volume of air accompanying rice flours with different particle sizes was measured, and its effects on porous structure of fermented bread made from rice flours of various particle sizes were investigated. Rice flour was divided in order of the particle size into 5 classes; 208-295μm, 147-208μm, 104-147μm, 61-104μm and below 61μm. The amounts of accompanying air of these 5 classes were determined by measuring apparent density; 0.8, 1.8, 1.9, 2.4 and 1.0cm³/kg-D, respectively. The amounts of accompanying air of 4 classes except the class of below 61μm were a few times larger than the volume of micropores (smaller than 30nm in diameter) inside the rice flour particles. Each fraction of sieved rice flours, mixed with water, sugar and yeast was fermented and steamed to rice breads. The loaf volume of 5 rice breads were about 1.2cm³/g. The pore size of porous structure inside rice breads of 4 classes except the class of 208-295μm, measured by microscopic observation, showed approximately logarithmic normal distribution. The amounts of accompanying air of the rice flour had a positive correlation (r=0.999) with pore number, and a negative correlation (r=-0.985) with median diameter of pores inside rice breads of 4 classes except the class of 208-295μm. Any correlation was not detected with the standard deviation of pore size distribution. It became clear that the air accompanying flour particles had an effect on the porous structure, especially on the pore number, of steamed goods prepared through the process of fermentation.

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A new method for selective determination of heme and nonheme iron has been developped. Heme iron in animal foods was extracted with 80% acetone (acidified with hydrochloric acid below pH1.0). Nonheme iron in animal foods was extracted with 1% hydrochloric acid at 80°C. After adjusting acetone concentration of extracts to 40%, solutions were passed through Sep-Pak C18 cartridge column. Heme was adsorbed on the column, while nonheme iron was passed through the column. Heme was eluated out from the column with acidified 80% acetone. Eluates containing heme iron or filtrates containing nonheme iron were evaporated, then wet digested with nitric acid and perchloric acid. Residues after wet digestion were solubilized in 1% hydrochloric acid and iron in solutions was determined by AAS. This method showed that the sum of heme and nonheme iron content of various animal foods was the same to as total iron content determined by the wet digestion-AAS method. The ratio of heme iron to total in processed animal foods were almost same rate in the raw material meat.

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Bread heated with microwave is well known to be rapidly stale. This rapid staling was never observed on bread heated by ordinary thermal treatment. Staling mechanism of bread heated with microwave has not been fully understood due to its complexity, although some studies have been reported on changes in the starch-gel and the bound water in bread. In this study, the role of starch and gluten on staling was investigated for white bread treated with microwave-heating. In order to elucidate staling mechanism more precisely, we have used breads, starch-gel and gluten-gel with/without monoglyceride. The results are summarized as follows: (1) The rapid hardening of microwave-heated bread was mainly caused by hardening of starch, of which a main factor was the changes from sol to gel on starch in bread. (2) Crystallization (retrogradation) of starch in bread contributed greatly to the gradual hardening after rapid hardening in the primary process. (3) Starch and gluten were both concerned as well with a decrease in crispy property of bread after microwave heating. Gelatinization and elution of starch, and reinforcement of gluten network caused the decrease of its crispy property.

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Allylisothiocyanate (AITC) inhibits ethylene production and browning of shredded cabbage. To investigate its inhibitory mechanism, we compared effects of AITC with those of several inhibitors on ethylene evolution and browning. Only AITC and cycloheximide, a protein synthesis inhibitor, suppressed both ethylene production and browning in shredded cabbage. Phenylalanine ammonia-lyase (PAL) is a limiting enzyme of polyphenol biosynthesis and is known to be induced by tissue wounding. In this experiment, we found that AITC treatment on shredded cabbage suppressed both PAL activity and PAL protein amount. From these results, AITC was considered to act as an inhibitor for PAL induction in shredded cabbage.

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Antioxidative activities of ethanol extracts of 150 mushrooms species were studied. About one-third of the species showed a significant antioxidative activity on methyl linoleate. Among them, 27 species had especially strong antioxidant activities. From the taxonomycal point of view of fungus, it was found that many species belonged to Boletaceae had strong antioxidant activities and most of species belonged to Suillus especially showed very strong activities. Since tocopherol contents of mushrooms were more or less 150 μg/100g dry matter, it seemed to be that tocopherol was not main antioxidant components. The antioxidant components of many species were extracted with polar solvents. However some species such as Amitake, Oogitake, and etc. showed strong antioxidant activities on the extracts with nonpolar solvents. Marked differences were not found in antioxidative activities between oil system and emulsion system.

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Monostoroma nitidum ("Hitoegusa"in Japanese), a kind of greenish seaweeds, is used as a raw material for "Nori-Tsukudani." Strong antioxidative activity was found in ethylacetate-soluble fraction of its methanol extract. Several unidentified component in this fraction showed the activities. "Nori-Tsukudani" is made of Hitoegusa, soy sauce and sugar by heating at ca. 80°C for 30min. The antioxidative activity was stable at such a high temperature, under an acidic and alkaline conditions and also under the presence of high concentration of salt and sugar. The ethylacetate-soluble fraction of soy sauce, which also showed an antioxidative activity, synergistically enhanced the activity of Hitoegusa.

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To study physiological functions of miso at cellular level, the effects of extracts of some miso dregs on the cultured biophylactic cell lines such as monocytic (U-937), macrophage-like (U-M), hybridoma (HB4C5) and T Cell-derived (MOLT-3) cell lines were examined. The dialyzates of 0.1 N NaOH extract of barley and rice miso dregs enhanced the nitroblue tetrazolium (NBT) reducing activity of U-937 monocyte and U-M macrophage-like cell lines. The dialyzates of 0.1 N NaOH extract of barley miso dregs enhanced the IgM production of human-human hybridoma cell line, HB4C5. It was also found that the dialyzates of 0.1 N NaOH extract of rice miso dregs activated the T-cell-derived Molt-3 cell line.

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Natto's appearance, temperature, number/g of B. natto, hardness and color tone during fermentation were investigated at different temperatures (30, 35, 40, 45°C) with different inoculum sizes (10², 10⁴, 10⁶, cells/g). At a low temperature down with an decrease in inoculum size the fermentation rate was slowed. When the incubation temperature was high, Natto's temperature was also high. At higher temperatures and larger inoculum sizes, the growth rate of B. natto was faster. The hardness continued increasing through the 30 hours of fermentation, and showed higher values at higher temperatures and larger inoculum sizes. The change in Y% was opposite to those in x, y values. The z value increased during“gray green stage”. Natto's fermentation was kept in good conditions at 35°C with an inoculation of 10⁴-10⁶ cells/g or at 40°C·10²-10⁴ cells/g of the starter, judging from the appearance, color tone and hardness at 18-20 fermentation hours.

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Natto's protease, γ-glutamyltranspeptidase (γ-GTP) and levansucrase (L.S) activities, solubilization and hydrolysis ratios of proteins, and the stringiness of a viscous substance were investigated during fermentation at different incubation temperatures (30, 35, 40, 45°C) with different inoculum sizes (10², 10⁴, 10⁶ cells/g). The protease activity increased contintously during the 30 hours of fermentation, and the activity increased in the order of pH 5.7 <10.0≤7.0. With lowering the temperature the protease activity appeared later but the protease production rate was faster. Solubilization and hydrolysis of proteins also increased through out the 30 hours of fermentation with a rice in temperature, but these increasing rates were slowed down at 45°C. The γ-GTP activity increased during the 30 hours of fermentation, and the rate of Natto's γ-GTP production at 45°C was slowest. L.S activity increased at log phase, and decreased after than. The stringiness of Natto in creased with time in fermentation at 30°C during 30 hours. At 35-45°C the stringiness showed maximum values, and decreased a little after than, in samples with karge inoculum size. The protease activity was kept high in Natto produced at 30-40°C, and γ-GTP activity, solubilization and hydrolysis of proteins and stringiness were kept high in Natto produced at 35, 40°C at 18-20 fermentation hours.

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