A fruit flavour solution was packaged into several kinds of pouches (Polyethyleneterephthalate (PET)/Aluminum foil (Al)/Polyethylene (High-density: HDPE, Middledensity: MDPE, Low-density: LDPE, Linear low-density: LLDPE, Ehylene vinylacetate copolymer: EVA)) and the sorption behavior of volatile compounds in the solution by plastic materials was investigated. (1) The distribution ratios (content in film/solution) of volatile compounds increased approximately linearly until 20th day, but after that, were almost constant. (2) The distribution ratios were influenced by functional groups of the volatile compounds. In homologous series, the distribution ratio increased with increasing carbon numbers. (3) Higher level of sorption was observed in CPP pouch than in HDPE one. (4) Among HDPE, MDPE and LDPE pouches, the distribution ratio was closely correlated to the density of film; r=-0.90--1.00. (5) The distribution ratios in LLDPE and EVA did not correlate to the density of film because quaternary carbons and vinylacetate units affected the sorption.

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Changes in distribution of low molecular weight carbohydrates, polysaccharides and organic acids were followed in the mycelia and fruit-bodies of Shiitake mushroom (Lentinus edodes) grown on a glucose-peptone medium. (1) The total free sugar content in mycelia during development was found in the range of 3.4-7.8%, in stipes 3.7-5.2%, and in pilei 4.3-6.6% in dry materials, respectively, while the total sugar alcohol content in developing mycelia was 1.6-4.7%, stipes 7.7-9.9%, and in pilei 6.6-7.1%, respectively. In the mycelia and fruit-bodies, trehalose, mannitol, arabitol, glucose, fructose and glycerol were identified, and trehalose, mannitol and arabitol were found to be major among them. Trehalose, mannitol and arabitol were supposed to function as the main translocating carbohydrate. (2) The content of polysaccharides in mycelia during development was found in the range of 53.5-59.3%, in stipes 48.7-51.6%, and in pilei 38.3-39.5% in dry materials, respectively. The contents of four polysaccharide fractions, that is, hot alkaki-soluble fraction, alkali-soluble, acid-insoluble fraction (S-glucan), formic acid-soluble fraction (R-glucan) and alkali-soluble, acid-soluble fraction, did not change during the development. Acetic acid-soluble fraction predominated in the polysaccharide fractions of the mycelia, but was the minor constituent in fruit-bodies. Acetic acid-soluble fraction accumulated in mycelia was supposed to function as the reserve carbohydrate. Utilization of chitin in mycelia also occurred during development. (3) The organic acid content in mycelia during development was found in the range of 0.8-3.1%, in stipes 1.4-1.5%, and in pilei 2.7-2.9% in dry materials, respectively. In this mushroom, eleven kinds of organic acids were identified. Pyroglutamic, malic, citric and fumaric acids were found to be predominant in mycelia, stipes and pilei. There were remarkable differences in the distribution patterns of their rganic acid compositions among mycelia, stipes and pilei.

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Antioxidatve activity of ascorbyl stearate and/or its synergistic effect on tocopherol and nitrogen containing compounds were investigated on linoleic acid in aqueous system at pH 7.0 and on lard by AOM. The following results were obtained. (1) The antioxidative activity of ascorbyl stearate on linoleic acid was hardly recognized, but its synergistic efffct on amino acids and natural tocopherol were observed. (2) A comparison of the antioxidative activities of glycine and three kinds of peptide containing glycine indicates the stronger activity of dipeptide than other peptides and the stronger synergistic effect on ascorbyl stearate. (3) Ascorbyl stearate showed hardly the antioxidative activity on lard by AOM. However, the synergistic effect was observed in the combination of ascorbyl stearate, dl-a-tocopherol and lecithin on lard by AOM.

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Changes in the contents of low molecular weight carbohydrates, polysaccharides and organic acids in pilei, stipes and bases of stipes of fruit-bodies of Hiratake mushroom (Pleurotus ostreatus) during development and post-harvest storage at 20°C were investigated. (1) The total free sugar content in the mushroom during development was found in the range of 6.8-15.6% in pilei, 10.1-27.2% in stipes, and 9.3-24.9% in bases of stipes on the dry weight basis, respectively, while the total sugar alcohol content was 3.0-3.8% in pilei, 3.2-3.6% in stipes, and 1.0-2.9% in bases stipes, respectively. In this mushroom, trehalose, mannitol, glucose, fructose and arabitol were identified, and trehalose and mannitol were found to be major among them. The content, of each element varied individually during the development, and there was remarkable difference among pilei, stipes and bases of stipes. During post-harvest storage, the contents of each element, except mannitol, decreased. Especially the decrease of trehalose was marked. The content of mannitol during post-harvest storage increased for the first three days, but it decreased from then on. (2) The polysaccharide content in the mushroom during development was found in the range of 40.3-44.3% in pilei, 47.3-50.2% in stipes, and 54.2-55.8% in bases of stipes respectively. The contents of five polysacchride fractions-formic acid-soluble fraction (R-glucan), alkali-soluble, acid-soluble fraction, hot alkli-soluble fraction, alkali-soluble, acid-insoluble fraction (S-glucan) and chitin-showed no change during development and post-harvest storage, but the content of acetic acid-soluble fraction decreased during storage. (3) The organic acid content in the mushroom during development was found in the range of 3.6-4.4% in pilei, 4.5-5.1% in stipes, and 6.0-7.4% in bases of stipes. In this mushroom, eleven kinds of organic acids were identified. Malic, pyroglutamic, fumaric, succinic and citric acids were found to be major among them. There were remarkable differences in the distribution patterns of their organic acid among pilei, stipes and bases of stipes. During post-harvest storage, the contents of each element increased without exception.

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Soybean glycosides have been shown to have undesirable taste such as bitterness and astringency. In the undesirable taste of isolated glycoside components, the order of their intensities was as follows; soybean saponin A group, B group, daizin, and genistin. As A group was found only in the hypocotyl of soybean seed and daizin was also rich in the hypocotyl, it is effective to remove seed coat and hypocotyl before soaking, to decrease undesirable tasting glycosides of these foods. Moreover, these glycosides were hardly extracted from soybean meal at lower temperature, therefore, squeezing rare soymilk without heating is also important for reduction of the glycosides in soymilk and tofu processing. In this paper, effects of removing seed coat and hypocotyl and squeezing without heating on quality of tofu were studied by texture profile analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and sensory evaluation. Cotyledon tofu which was made from cotyledon only was firmer than whole soybean tofu. From the structure of each tofu observed by electron microscopy, we found that oil droplets are evenly dispersed in cotyledon tofu, while oil droplets cohered in whole soybean tofu. The phenomenon of the latter tofu seemed to be responsible for the oily taste. The saponin fractions prepared from tofu were analyzed by TLC and HPLC. The most undesirable component group (A group) was less in cotyledon tofu than in whole soybean tofu. Sensory evaluation of tofu was designated as color, taste and texture, and those of cotyledon tofu were highly evaluated than those of whole soybean tofu.

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Employing the modified method reported previously, free and esterified fatty and organic acids in various samples of Natto (9 varieties of Itohihi-natto and 6 varieties of Tera-natto) were determined to compare with those of common Miso. The results were as follows. (1) Ethylesters of fatty acids rich in the common Miso were not detected in Itohiki-natto, but slightly found in Tera-natto. (2) Lactic acid was the dominant organic acid whose contents was 470.1mg/100g in Hama-natto, and 26.2mg/100g in Tera-natto and was not detected in both Itohihi- and Hoshi-natto. (3) The average contents of the major volatile organic acids in Itohihi-natto were: acetic acid (124.7mg), propionic acid (28.4mg), isobutyric acid (44.1mg) and iso-valeric acid (46.7mg) per 100g. On the other hand, the last two acids which gave unfavorable odor at higher concentration were found in a small amount in Hama-natto and Teranatto. Iso-Valeric acid content in the Teranatto was less than one twentieth of that in Itohihi-natto.

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Sausage was manufactured for trial from sardine dress. The dress was minced, cut with sodiun chloride under vacuum (15mmHg) to sol, then heated at 80°C for 30min in a polyvinylidene chloride tube to gel. (1) The resulting gel resembled sausage rather than Japanese style kamaboko. (2) The gel was strengthened by setting the sol at 30°C before heat treatment at 80°C, by rising its pH, or by the addition of sodium pyrophosphate. (3) The gel was strengthened also by the additives, such as wheat flour, corn starch, dried egg white, wheat protein and soybean protein, among which the last three were especially effective. (4) The decoloration of the gel during cold storage was suppressed by cutting the mince under vacuum. In this case, the evolution of fishy odour from the gel and the increment of POV of the oil within it were also suppressed

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Sixteen soy sauce samples and 6 fish sauce samples produced in Asian countries were characterized for melanoidin by electrofocusing on polyacrylamide gel and high performence gel permeation chromatography (HPGPC). Melanoidin of soy sauce was electrofocused into 7 bands at pH range of 2.5-3.5. Melanoidin of fish sauce did not give a clear electrofocusing profile. The model melanoidin of glucose and glycine system was different from the melanoidin of soy sauce which contained components electrophoresed to the direction of the cathode. The pattern of the major bands was almost similar in all the soy sauce samples tested, but the intensity of the pigment which was retained at the charged position greatly varied. The mean molecular weight of the retained brown pigment in most samples was larger than those of electrofocused pigments by HPGPC. Broad HPGPC peakS were noted in the soy sauce samples added with caramel except one Korean soy sauce. Mean molecular weight and color intensity of fish sauce are mostly smaller than those of soy sause. The pH value is higher in fish sauce than in soy sauce.

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Effects of dietary soybean oil, coconut oil, lard and beef tallow on the changes in triacylglycerol (TG) composition and structure in egg yolk lipids of laying hens were studied. Generally, the fatty acid composition of egg yolk TG reflected partially that of the dietary fats fed to hens, though, the short chain saturated fatty acids (C8:0, C10:0) were not availably utilized for the egg yolk lipid formation. Egg yolk TG from hens fed soybean oil, lard and beef tallow was commonly composed of C50, C52 and C54 species as main TG components. More TG species of C44-C50 were contained in egg yolk of coconut oil group than in that of the other diet groups, while, C52 and C54 components were less in coconut oil group. Egg yolk lipid of soybean oil group contained less amounts of TG comprising monoenoic acids and more of TG comprising dienoic acid than the other groups. Lipid of coconut oil group contained the most amount of S2M and the least of U3 among the experimented diet groups. Lipids from lard and tallow group comparatively resembled each other in distribution pattern of TG species. In egg yolk TG from every dietary group, saturated fatty acids were preferentially esterified at position 1 of TG, on the contrary, position 2 comprised predominantly unsaturated fatty acids. Position 3 was largely occupied by C18:1 accompanied with C16:1. This species specificity of positional distribution of fatty acids in hen's egg TG was not changed regardless of variation of dietary fats fed to hens.

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Acetoin and 2, 3-butanediol were found to accumulate and reach a maximum in "natto" after 12h of fermentation (acetoin: 495mg/100g and 2, 3-butanediol: 748mg/100g on dryweight basis, respectively), after which these amounts decreased as a result of the action of microorganisms. Prior to this period, the level of citric acid, the major organic acid of soybeans, and glucose released from sucrose, decreased remarkably. Acetic acid increased gradually during the latter half of fermentation and showed irregular variations during storage (100-573mg/100g). Propionic acid was detected from the middle of fermentation and its increase was affected by storage temperature (8-57mg/100g). Three branched-chain fatty acids (iso-butyric, 2-methylbutyric, and 3-methylbutyric acids) were detected after 12h of fermentation and increased thereafter. During storage at 25°C, the contents of these acids were increased remarkably (iso-butyric: 313mg/100g, 2-methylbutyric: 373mg/100g and 3-methylbutyric: 131mg/100g, over 15 days, respectively). However no such change was observed during storage at 5°C or 15°C.

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