The effects of nitrite on destruction of bacteria related to the fermented pickles were investigated. Gram negative bacteria, Streptococcus, Leuconostoc were destructed earlier by adding 50μg/ml nitrite to fermented pickles. Destruction of nitrite producing bacteria was accelerated by nitrite under acidic conditions, and this effect on the strains belonging to Pseudomonas, Klebsiella, Micrococcus, Enterobacter increased in this order. Accelerating effect of nitrite on destruction of lactic acid bacteria belonging to Streptococcus, Leuconostoc, Pediococcus and Lactobacillus increased in this order. It was found that the growth of lactic acid bacteria and the lowering of pH were inhibited under the condition that the number of nitrite producing bacteria was much more than that of lactic acid bacteria and the concentration of nitrite was high.

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This paper describes the effect of surrounding factors on the accumulation of nitrite produced by bacteria related the fermentation of pickles and their nitrate reductase activities. The strains belonging to Pseudomonas grew at 20-30°C and accumulated nitrite at 10-30°C favourably. The strains belonging to Enterobacter and Klebsiella grew at 30-40°C favourably and accumulated a large amount of nitrite in the same temperature range. The strains belonging to Pseudomonas grew and accumulated nitrite successfully without NaCl, but failed the growth and nitrite production under the conditions with above 4 % of NaCl. On the other hand, the strains belonging to Enterobacter and Klebsiella grew and accumulated nitrite even in the presence of 6% NaCl. Though the nitrate reductase activity of the strains belonging to Pseudomonas lowered dramatically with increasing NaCl concentration, the effect of NaCl concentration on those of the strains belonging to Enterobacter and Klebsiella was relativily small. Nitrate reductase was activated by malic and lactic acids. Therefore, it was supposed that malic acid contained in vegetables used for pickling contributed to the production of nitrite in the fermented pickles. The nitrate reductase of the strains belonging to Pseudomonas was also activated by fructose, and that of the strains belonging to Enterobacter and Klebsiella was remarkably activated by glucose and fructose.

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The nondialyzable melanoidin prepared from D-xylose and glycine was decolorized by C. versicolor IFO 30340. The antioxidative activity of decolorized products on linoleic acid in aqueous system at pH 7.0 was investigated. By cultivation of C. versicolor in the basal medium containing melanoidin at 30°C for 12 days, its brown color was decolorized about 80 %. However, the decolorized melanoidin showed the same antioxidative activity as that of the melanoidin. By fractionating both media before and after cultivation with Sephadex G-25 column, the former gave only one peak by monitoring an optical density at 420nm, but the latter showed two peaks; high molecular melanoidin and low molecular one. On the other hand, both media gave two peaks on the same column by determination of total organic carbon, respectively. In the former, the low molecular substance was glucose added into the medium, but in the latter, unknown and considered to be the decolorized products by C. versicolor. When antioxidative activities of both substances in the decolorized melanoidin were compared at same weight level, strong antioxidative activity was distributed in the low molecular one. IR-spectrum of the melanoidin showed shoulder absorption at 1720cm^-1, but that of the decolorized one revealed sharp absorption of carbonyl group at same wave-number.

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The corrosion of aluminum by commercial beer was detected through electrode potential shifts and polarization curves under constant potential electrolysis. The amount in ppb of dissolved aluminum was measured by a frameless atomic absorption spectrophotometer. The main results obtained are as follows. (1)Aluminum is corroded by beer along the way of the general corrosion. (2)A distinguishable amount of aluminum was detected in beer surrounded by coated aluminum. (3)The amount of dissolved aluminum in beer kept at 5°C for 5 months was less than that in beer kept at room temperature for the same period. From these results, it is clear that aluminum cans can be corroded by commercial beer.

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Bacterial spoilage of film-packaged kamaboko in cold storage was investigated microbiologically. The softening of tissue and the production of fluorescent pigments were observed in a spoiled portion of kamaboko. The causative bacteria was isolated from the spoiled kamaboko, and an isolated strain was identified as Pseudomonas fluorescens biovar V based on Bergey's manual of systematic bacteriology volume 1. The characteristics of P. fluorescens IFO 3081 and the isolated strain showed the following results.The G+C molar percentage of DNA in the isolated strain was 60.76%, which nearly coincides with 61.06% in P. fluorescens IFO 3081. The proteolytic activity of the isolated strain was positive, but that of P. fluorescens IFO 3081 was negative. The isolated strain could grow at -2°C but not at 38.5°C, and the optimum temperature for growth was from 30 to 31°C. Therefore, the isolated strain may be psychrotrophic bacteria, which coincides with the characteristics of facultative psychrophile. When the isolated strain was inoculated onto kamaboko, the softening and production of fluorescent were observed on its surface, but P. fluorescens IFO 3081 did not cause spoilage. From the results that the isolated strain and P. fluorescens IFO 3081 were different in proteolytic activity, it is supposed that bacterial proteases may play an important role for growth of the genus Pseudomonas on the surface of kamaboko.

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Effects of carbon and nitrogen sources on the vegetative growth of kuritake mushroom [Naematoloma sublateritium (Kr.) Karst.] were investigated using a liquid culture medium. A wide range of carbohydrates was utilized as carbon sources in the medium which supported growth of kuritake mushroom. Trehalose, glycogen, soluble starch, dextrin, mannose, glucose, maltose and fructose were especially good carbon sources for mycelial growth. However, ribose, fucose, rhamnose, galactose, sorbose, lactose, melibiose, sucrose, raffinose, erythritol, arabitol, mannitol, galactitol and inositol were not effective as carbon source. The optimal concentration of carbon source was less than 3%in case of glucose. The optimal carbon/nitrogen ratio in the medium was about 20/1. Yeast extract, soyton, peptone, meat extract, Casamino acid and the amino acid mixture of the basal medium were acceptable nitrogen sources for the growth. On the other hand, ammonium and nitrate salt were poor as nitrogen source for mycelial growth. The Casamino acid in the culture medium could be substituted by the nine amino acids as follows; glycine, L-alanine, L-leucine, L-isoleucine, L-valine, L-aspartic acid, L-glutamic acid, L-arginine, and L-serine.

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The carotenoids in fresh and salted sea urchin gonads were analyzed by high-performance liquid chromatography. The content of carotenoids as a whole was 13.79mg per 100g of fresh gonads. The amounts of echinenone containing its cis-isomer, lutein, isozeaxanthin, α-carotene, β-carotene and isocryptoxanthin accounted for 55.9, 11.5, 9.4, 3.0, 3.0 and 0.7% of the total carotenoids infresh gonads, respectively. The amount of total carotenoids in the gonads salted with 7% NaCl together with 10% ethanol decreased slightly during 180 days ripening, while that of the gonads salted with 20% NaCl was stable throughout ripening. The slight decrease in total carotenoids observed in salted gonads (7% NaCl and 10% ethanol) may be attributed to some enzymatic reactions, because total carotenoids in heated and salted gonads did not decrease through 180 days ripening. α-and γ-Tocopherols remained constant in salted gonads even after 180 days ripening. It seems that tocopherols suppress oxidative decomposition of carotenoids.

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The effect of lipids from sea urchin gonads on the autoxidation of methyl linolenate (MLn) was investigated. The residual MLn was determined by gas liquid chromatography during incubation of an oxidation system at 37°C in the dark. The additions of total lipids (TL) and neutral lipid fraction (NL) prolonged the induction periods of MLn autoxidation from 1 day of control system to about 10 days and 4 days, respectively. When glycolipid fraction (GL), phospholipid fraction (PL) or NL without tocopherol was added to the oxidation system, the induction period was not prolonged. The addition of combination of NL+GL+PL, NL+GL or NL+PL retarded the autoxidation of MLn, while the combination of GL+PL accelerated it. α-Tocopherol showed the same antioxidant activity as NL. PL decomposed MLn hydroperoxides at the initial stage of autoxidation. These results suggested that tocopherol retarded the autoxidation of lipids synergistically together with GL and PL during the storage of salted sea urchin gonads.

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by ripening at 20°C for 6 months. After 24hr of incubation the pH of the sausage was decreased to 4.7 and kept at the constant level during 6 month-ripening. The degradation of meat proteins in the sausage was detected by SDS-PAGE and peptide analysis. The total amount of free amino acids increased; the increases of Glu, Gly, Ala, Val, Leu, Lys were especially large. Except the increase in Lys, these results were in accord with the changes on porcine meat conditioning. Since the starter culture had a little effects on the proteolytic changes and relatively low proteolytic activity was found in lactic acid bacteria, it seemed that the proteolysis in the fermented sausage prepared by lactic acid bacteria was primarily caused by endogenous proteases in meat. Nevertheless, some changes in the free amino acid content and SDS-PAGE patterns implied that lactic acid bacteria was involved to some extent in proteolysis of the fermented sausage.

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An ethanol fermentor with immobilized Saccharomycodes ludwigii cells entrapped in calcium alginate gel beads and an acetic acid fermentor with immobilized Acetobacter aceti cells entrapped in calcium alginate gel beads were prepared. A bioreactor as-sembled from these two fermentors in series was used for continuous production of vinegar. A saccharified rice medium containing glucose (81g/l) and acetic acid (11g/l) was fed to the bioreactor continuously at a flow rate of 35 to 48ml/h. Rice vinegar containing 4.7 to 5.3% acetic acid was produced at the total residence time of two fermentors of 11.4 to 15.3h. These results suggest that the bioreactor devised here is suitable for a new type of vinegar production.

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The ascorbic acid content was analyzed and compared on acerola fruit harvested at three different production regions, with three degree of maturity, namely, pale greenimmature, pale red-half mature and red-ripe mature. the results were as follows.The ascorbic acid content of pale greenimmature fruit was the highest, 3200mg/100g, and decreased with fruit maturation. The ratio of reduced ascorbic acid to total ascorbic acid reached to almost 90%, therefore, acerola fruit was excellent source of supply for ascorbic acid as regards nutritional value. Among the three different regions, the ascorbic acid content was high in the order: Nago>Naze>Ibusuki. Accordingly, it was recognized that the ascorbic acid content was higher as a growing region goes more south. Regarding to the stability of ascorbic acid in acerola juice by heat treatment, unripe fruit juice (initial 2435 mg/100g) showed high retention ratios such as 88% at 80°C for 40min and 85% at 100°C for 40min. the ascorbic acid content in the leaf was not high, compared with that in fruit.

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Polyphenols in banana buds were found to consist of flavanan tannin (condensed tannin) as the major component; catechin, its oligomers, dopamine and dopa as minor components. Total phenol and vanillin-positive phenol were higher in the buds of cultivars Bungulan, Lacatan and Latundan and lower in the buds of cv. Saba. Polyphenol oxidase (PPO) in cv. Saba was localized in the male flower; 3 times less in the peduncle and bract; and about 30 and 300 times less in the peel and pulp of the fruit respectively. PPO activity in the male flower, peduncle and bract was inhibited by 0.13M NaCl about 20 to 30%, while that in the peel and pulp was inhibited about 40 to 50%. Buds of the other cultivars had similar levels of PPO which were inhibited about 20% by 0.13M NaCl. The Ki value for NaCl of PPO in the peel was estimated to be 0.28M. The astringency, bitterness and color of banana buds were monitored before and after heating, NaCl treatment and squeezing. These are discussed with reference to the polyphenols and PPO focussing on food quality.

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Proteinases and aminopeptidases of B. linens, which are involved in the protein breakdown of surface ripening cheeses, have potential application for accelerated ripening of hard cheese. Both enzyme activities were found to be higher in extracellular than intracellular preparations. Sodium chloride inhibited aminopeptidase production but not proteinase production. Aminopeptidase was produced at the stationary phase of the growth while proteinase was produced in the beginning of logarithmic phase. Optimum medium composition and characterization of crude enzyme are described.

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