Anthocyanins isolated from "Sordum" plum were purified by paper chromatography. They were characterized by spectroscopy, hydrolysis and paper chromatograpy. Main anthocyanins were identified as cyanidin-3-monoglucoside and cyanidin-3-rhamnoglucoside. They amounted to 91percent of the total anthocyanins is "Sordum" plum.

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As shown is stored Tenobe-somen, lipids in raw products of wheat flour may be hydrolyzed during long storage, and the change of lipids may have some effects on the gelatinization of wheat flour on cooking. Among the lipids tested, fatty acids and monoglycerides inhibited the swelling of wheat starch on heating, while egg yolk lecithin promoted it. Cottonseed oil had no significant effect. The inhibitory effect of fatty acids disappeared at a high temperature of 95°C. But when wheat flour was used instead of wheat starch, or when wheat starch was heated in the saline water extract of wheat flour, the inhibitory effect of fatty acids was observed even at 95°C. The same effect of fatty acids was observed when bovine serum albumin, bovine serum α-globulin or wheat gluten was added to wheat starch. On the basis of above observations, it was concluded that proteins in wheat flour played an important role in controlling the swelling of starch in flour products. The contribution of proteins could be accounted for only partly by their effect of pH control.

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An improved enzymatic method using 4-aminoantipyrine and p-hydroxybenzoic acid for the determination of D-glucose in soy sauce is described. The reagent 4-aminoantipyrine is not carcinogenic unlike the reagent o-dianisidine formerly used. In the procedure, D-glucose is oxidized by glucose oxidase to D-gluconic acid with the simultaneous production of hydrogen peroxide, which oxidatively couples with 4-aminoantipyrine and p-hydroxybenzoic acid in the presence of peroxidase to yield a quinoneimine dye with maximum absorption at 500nm. The method requires no specific pretreatment of samples other than simple dilution. The calibration curve is linear to 100mg/dl. Many substances that may be encountered in soy sauce do not interfere the quantitative reaction. An efficient automatic assay method was established by the use of this procedure with a new discretetype auto-analyzer. In addition, the behavior of various neutral sugars in the soy sauce brewing process was traced using by ion-exchange liquid chromatography. Adistinct decrease of glucose appeared at the same time when brewing microorganisms (Pediococcus halophilus, Saccharomyces rouxii, Torulopsis) grew actively, though the changes of the other sugars were not so prominent. These results suggest that the determination of glucose, not of reducing sugars, has a more practical meaning in the control of fermentation during the process of soy sauce brewing.

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(1) Accelerating effect for acetic acid fermentation employing No.2 strain accepted from National Institute of Fermentation Technology, Ibaraki-ken, was found in yeast extract, koji extract, sake cake, malt extract and molasses added into media. In paticular, yeast extract was most effective to reduce the lag time of the growth and increase the amount of acetic acid produced. (2) Effective substances in the yeast extract were separated into three fractions, an acidic, a basic and a neutral fraction with a chromatography employing Amberlite IR-120 (H⁺) and IR-4B (OH^-). Among the three fractions, an acidic fraction showed the most stimulative effect. It was confirmed that the stimulative effect was caused by the organic acids including lactic, pyroglutamic, and succinic acid, as the result of chemical analysis and microbial test. (3) Effective substances in neutral fraction were considered as glycerol, sucrose and ribose as the result of bioautography, gas chromatography and column chromatography on LC-R-3 ion exchange resin. From the amino acid composition in the basic fraction, it was estimated that the stimulative effect of this fraction was due to the amino acids including alanine, glutamic acid, and aspartic acid.

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Chicken muscles lose their freshness faster than beef or pork, which largely affects its quality. Therefore, by measuring changes of pH, volatile basic nitrogen, amino type nitrogen, live bacteria count and K value of chicken muscles in storage, adequate indices of chicken freshness were examined. As a result, it was concluded that K value obtained by qualitative changes of ATP related substances constituted an effective marker indicating chicken freshness, by considering that K value changes to a greater extent than the other measurement items and that it begins to increase from its slaughten on. At higher temperatures in storage, K value was increased more quickly. However, when chicken muscles were stored at -30°C, K value did not show a great change for a year. The phosphatase activity of thigh muscles was higher than that of breast muscle. In thigh muscle which is consisted of musculus complexes, K value varied according to muscular sites in storage, showing a faster increase in more reddish muscle. Change in K value was compared among chicken species (broiler, hen, japanese game) as well as between sexes in storage, but there was not difference between them.

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The effect of pH and NaCl concentration on the extraction of the protein from walnut, "Shinano-Gurumi" (Juglans regia L.) was examined; 98.7% of the total nitrogen in walnut was extracted with a 10% NaCl containing NaHCO₃-Na₂CO₃ buffer solution system (pH 11.0), and on a dry basis, about 87.6% of the isolated fraction was protein. It was least soluble at pH 7.0, but its solubility increased to 96 and 90% respectively, at pH 3.0 and 11.0. Glu, Arg, Asp were rich and Cys, Met, His were poor in its amino acid composition. The isolated protein was characterized using an acetic acid-urea polyacrylamide gel electrophoretic system and sodium dodecyl sulfate (SDS) polyacryiamide gel electrophoresis: three main bands A1, A2, and A3 were estimated to have molecular weights of 42, 000, 39, 000 and 25, 000 respectively, on SDS polyacrylamide gel electrophoretical pattern. The content of sulfhydryl and disulfide bond in the protein was higher than soybean and yeast proteins.

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This work was carried out to elucidate changes of water holding capacity, residual NO^-₂ level, color forming ratio, and amount of nitrite and nitrate of cured pork loins during curing period (day) at 4°C. The experimental condition was based on the findings revealed by a previous study; the injection of 15% of pickle solution and 2.2% NaCl in weight ratio to fresh pork loins produced satisfactory results. (1) Water holdng capacity and pH value of cured pork loins gradually increased as the curing progresses. (2) Residual NO^-₂ of cooked cured loins produced respectively by addition of 100ppm of NaNO2, 100ppm NaNO2 with 300ppm of sodium ascorbate (NaAS)and 200ppm of NaNO₂ with 600ppm of NaAs, became relevant level, less than 70 ppm as NO^-₂, which is a quantity provided by Japanese Food Hygiene Law, within 2 days after curing. However, the loin products produced by addition of 200ppm of NaNO₂ without NaAs were under the necessity of curing for around 7 days to reach the accepted maximum level of NO^-₂. Color forming ratio of cooked cured loins underwent almost no change during the curing period. (3) Flavor, like aroma, revealed after curing and processing was distinctively perceived in part of final products of loins after 4 days curing, while 7 days curing was need to give satisfactory such palatability characteristic for all employed samples. (4) Although completely uniform distribution of NaCl was not achieved in loins under this experimental condition, the curing period of 3 days or more resulted in relatively equal distributions, which gave a feeling of satisfactory quality. (5) Decomposition of nitrate into nitrite, which is analytically detectable in cured loins, was caused in some of those at 10 days curing, but 14 days curing was necessary to do so for all of them.

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[in Japanese]

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