An investigation was made of the ground water samples for the distribution of drug resistant fecal coliforms and the carrying rate of R plasmids, because the potential contamination of the aquatic environment including drug resistant pathogenic bacteria has been pointed out. Fecal coliforms were found in 59.1% of untreated ground water samples collected from 22 wells for the food industry in Yamaguchi prefecture. Atotal of 1, 066 fecal coliforms were isolated, and their susceptibility to 8 drugs was examined. Drug concentrations employed to distinguish resistant isolates from sensitive isolates were 25μg/ml for tetracycline, kanamycin and streptomycin, 50μg/ml for chloramphenicol, ampicillin, nalidixic acid and rifampicin, and 400ug/ml for sulfisoxazole, respectively. Itwas determined that 39.8% of the total isolates were drug resistant and 9.7% of them carried R plasmids. Escherichia coli type isolates classified by the IMViC systemaccounted for 75.9% of the total drug resistant isolates. Varied drug resistance patterns and manym ultiresistant isolates also carrying transferable R plasmids were observed inthem. The observed resistance patterns of R plasmids were mainly multiple. These plasmids were often found to encode resistance gene to tetracycline, chloramphenicol, streptomycin and sulfis oxazole. The continuous observation hereafter and the establishment of control methods of drug resistance are desirable because these bacteria in the ground water appear to be increasing with time.

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The flavor of rice cooked with and with out mirin (a sweet sort of sake) was ana lyzed. A Tenax adsorption system was used to trap the flavor components of rice after coo king. Two kinds of recovery systems, open and circulating, were tried; the circulating sys tem gave more reliable results. The flavor components of cooked rice were analyzed by gas chromatography and gas chromatography-mass spectrometry. For rice cooked without mirin, about 130 peaks were detected and about 40 major peaks were identified. A lkanals, alcohols, alkenals, and ketones were the main components; n-hexanal was particul arly abundant. When mirin was added, the peak area on the gas chromatogram was less t han that of cooked rice without mirin. Decrease of alkanals was most significant, wi th the greatest decrease of n-hexanal. These findings were consistent with the results of earlier sensory tests. The addition of mirin did not result in new peaks on the chromato gram. These findings suggested that the decrease in the amounts of the volatile compou nds in rice cooked with mirin was caused by the amino-carbonyl reaction of some constituents in mirin and rice.

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The continuous production of L(+)-lactic acid with immobilized bacterial cells in sweet sorghum (Sorghum bicolor) medium was investigated. High lactic acid producing bacteria were screened and the best producer was identified as Lactobacillus casei subsp. casei. The amount of lactic acid produced and its purity were attained at 49.Og/l and 98%, respectively. Optimum pH was 7.0, and 40% of the maximum activity remained even at pH 4.0. Optimum temperature was 35°C. The addition of neutalizers, NaOH or NH₄0H doubled the productivity. Lactic acid in the medium with CaCO₃ causedno inhibition up to 2%, but 40% inhibition was observed at 5%. The lactic acid yield against sugar decreased as the sugar concentration increased.

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Effects of antemortem injection of proteolytic enzymes (papain, proteasesfrom A. sojae and A. oryzae, and collagenase from Clost . histolyticum) on culled chicken muscles were investigated. Promotion of degradation of Z-line constituent and increase of fragmentation of myofibrils prepared from the chicken muscles treated with papain and protease from Aspergillus were observed during the storage. Digestion of β-subunit, and splitting and swelling of in tramuscular collagen fibrils prepared from the chicken muscles treated with proteases from Aspergillus and collagenase were also detected during the storage. From the point of safety and economy, it seems that proteases from Aspergillus are promissing as a meat tenderizer.

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The amounts of hydrogen peroxide (H₂O₂) contained in 260 kinds (1621 samples) of agricultural, stockbreeding and aquatic products andtheir processed foods were determined by using oxygen electronic method. The results were as follows: (1) H₂O₂ in a almost all raw foods were not detected. (2) H₂O₂ contents in processed foods were generally much more than raw foods. (3) H₂O₂ in scallion picles, dried shiitake, sandeel-tsukudni, toasted purple laver, hitoegusa-tsukudani, dried hijiki, green tea, black tea, barley tea, roasted coffee beans, instant coffee powder, cocoa powder and common soy-sauce were detected more than 5 mg/kg. (4) Not more than 5 mg/kg, H₂O₂ contents in infusion of greent ea, black tea and coffee were found. (5) The change of contents of H₂O₂ in various foods was found during cooking process. The content in vegetables, fishes and meats increased during heating Process. h2o2 contents in algae decreased except dried shiitake in the soaking process.

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Some chemical and physical properties of starches from four varieties of yam(Deoscorea), Ichoimo, Tsukuneimo, Sagami-wase and Nagaimo were investigated. Thegranular size of starches in average were 21.77, 18.93, 18.24 and 15.91μm for Nagaimo, Ichoimo, Tsukuneimo and Sagami-wase, respectively. The starches of Nagaimo were thebiggest among them. (2) The starches of Tsukuneimo, Ichoimo and Sagami-wase showedC-type X-ray patterns, but Nagaimo starch was the C_A type. (3) Degradation degrees of allthe starches by hog pancreatin were very low, especially Nagaimo starch was digested only13% by the reaction for 24 hours. (4) The blue value of Nagaimo starch was the highest.Amylose contents was calculated as 21.5, 22.1, 23.1 and 23.6% for Nagaimo, Ichoimo, Tsukuneimo and Sagami-wase, respectively. (5) Nagaimo starch showed the highest valuein the swelling power, but the lowest in solubility. (6) Gel filtration patterns of isoamylasedebranched starches were divided into 3 fractions, but the ratio of the fractions 2 and 3 inNagaimo starch differed from that in others.

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In the previous paper, the conditions of the processing of, soybeans for Tempe making were reported. Soaking dehulled soybeans in a 0.2% aqueous solution of acetic acid for 4hours and then steaming the munder 0.8kg/cmcm² gave a good result for Tempe fermentation. In this paper, changes in various components during fermentation of Tempe prepared following the previous processing were investigated. Changes in the appearance of Tempe, the growth thermogram and mycelium weight of Rhizopus oligosporus during Tempe fermentation indicated that the R. oligosporus reached the stational phase within the fermentation period of 20 to 22 hours. The pH value changed little within 18 hours of fermentation and then rapidly increased. The color tone (Y value) during fermentation slowly decreased from the beginning and increased rapidly after 18 hours. The x and y values showed little change for the first 12 hours, a rapid increase from 12 to 24 hours and a sharp decrease thereafter. The total nitrogen decreased slightly after 12 hours whereas little change in the total amino acids was observed. Protein solubility score (water soluble nitrogen/total nitrogen×100) showed as slight increase within the first 18 hours and an obvious increase thereafter. Regarding the amount of free amino acids, aspartic acid, cystine, methionine, phenylalanine and arginine remained each at a constant level throughout the fermentation period, while other amino acids increased after 16 hours. However, the ratio of free amino acids of the most amino acids were low, except proline and alanine. The amount of total sugars decreased after 8 hours. The ratio of direct reducing sugars to total sugars (direct reducing sugars/total sugars×100) increased after 8 hours and showed a slight decrease after the stational phase of R. oligosporus. Regarding the change of the amount of sugars, a decrease in sucrose and an increase in glucose and fructose were observed after 8 hours. These facts indicated that most of the changes to the product was progressed by the fermentation of 20 to 22 hours, although continuous changes were seen thereafter.

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The relationship of flesh firmness to sugar composition of flesh was studied in Japanese persimmon fruits during treatment of removal of astringency and storage at 20°C. A decline in flesh firmness was observed during treatment for removing astringency and storage, accompanied with the decrease of sucrose and the increase of fructose and glucose.
Close correlation was obtained between the decline of flesh firmness and the decrease of the ratio of sucrose to total sugar. The coefficients of correlations were 0.771^***(n=102) (cv."Hiratanenashi") and 0.701^***(n=22) ("Hiratanenashi" and three other cultivars) during deastringency treatment and storage, respectively. Those for cv. "Sakushumishirazu", "Takura"and "Atago" during deastringency treatment were also 0.899^***(n=9), 0.934^***(n=9) and 0.612^*(n=9), respectively.

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Job's-tears (Coix lacryma-iobi L. var. Ma-yuen Stapf) seeds were mixed with brewery yeast cells (10% of Job's-tears seeds) and subjected to a single-screw extrusion cooking.Addition of yeast cells imposed no negative effects on the extrusion cooking. Bulk density of the product was 8.41ml/g and hardness by a Tensipressor was only 3.91kg. By the addition of the yeast cells, the extrudate was fortified with crude protein (143%), lysine (156%), threonine (121%), vitamin B¹ (269%) and vitamin B² (175%). Trypsin inhibitor in the bran of Job's-tears seeds (JBTI) was denatured by the extrusion cooking and the extrudates showed neither trypsin inhibitory activity nor immunochemical reaction with the anti-JBTI serum raised against purified JBTI.

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Effect of dietary miso on the cholesterol metabolism was examined in rats fed the diet containing 0.5% cholesterol and 0.15% sodium cholate. The inclusion of 20% desalted miso to the atherogenic diet significantly decreased the concentration of serum cholesterol throughout the 30 days experimental period. Serum triglyceride and phospholipid as well as hepatic lipid concentrations at the time of sacrifice (30 days) were in no way affected by dietary miso. The ingestion of the miso preparation doubled the fecal excretion of acidic steroids, while it increased only slightly that of neutral steroids. The dietary miso appeared to exert the potent hypocholesterolemic activity primarily through the enhancement of the catabolism of cholesterol to bile acids in rats fed an atherogenic diet.

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Seventeen polyhydroxyalkylpyrazines were isolated and identified from soy sauce by combination of ion exchange- and thin layer chromatography and gas liquid chromatography as trimethylsilyl derivatives. Five compounds were identified by comparison with chromatographic data and mass spectra of authentic polyhydroxyalkylpyrazines, and structures of the other compounds were indicated on the basis of their spectral data.

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A colorimetric procedure for the micro-determination of titanium dioxide (TiO₂) has been developed. The method incorporates wet-ashing and color development using dianti pyrylmethane. The yellow-to-orange color is quite stable. Interference from Fe³⁺ ion could be removed in the presence of ascorbic acid. More than 90% of TiO₂ spiked at the 10 and 100 μg/g levels were recvered from cheese and white chocolate. The proposed method is rapid, simple and accurate. The minimum level for determination of TiO₂ was 5μg/g when 2g of sample was assayed.

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