Bacteriological examination was conducted on cooked beans packed in film under vacuum, and the effect of sorbic acid (SOA) and furylfuramide (FF) was investigated for the preservation of the product. Three-layered plate method was very useful for bacteria counting, preventing the rapid spreading of colonies of Bacillus strains. More than thirty strains belonging to B. pumilus, B. megaterium, B. cereus, B. subtilis, B. licheniformis, B. circulans, B. coagulans, Clostridium acetobutyricum, and C. bifermentans were isolated from the products prepared with or without SOA and stored at 37°C for a few days, one and six months. For preventing the growth of non-spore forming bacteria found in the products pasteurized at 85°C for 45min., 1500μg/ml SOA or 10μg/ml FF was necessary at pH 5. 8. The effectiveness of these preservatives decreased significantly with the increase in the number of inoculated bacteria. Some strains isolated from the product, especially of Clostridium, exhibited an ability to decompose SOA. By addition of 1000μg/g SOA or 2.5μg/g FF, the product was preserved for 21 days at 37°C without any spoilage in appearance and without increase in number of bacteria more than 1010²-10³/g. About half of added FF was lost by heat-treatment and the rest disappeared rapidly during the storage, while SOA decreased to only a limited extent.

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Effect of prolonged cold storage of 3 or 4 months on the after-ripening of Bartlett pears was compared with that of normal period storage. Fruits stored for 3 months after-ripened at 7-10°C without any disorder except a slight tendency of shortening shelf-life, however, changes such as core-breakdown and tissue-browning developed during after-ripening of the fruits at 20°C. Fruits stored for 4 months did not show normal after-ripening at both temperature conditions. In the fruits submitted to prolonged cold storage, the rate of increase in water-soluble pectinate and pectate during after-ripening was lower than control. Protein-N in alcohol-insolubles, which usually increases during after-ripening, did not increase in the 3 months-stored fruits, and rather decreased in the 4 months-stored ones during their after-ripening treatment.

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Esterase produced by microorganisms which catalyze butyl p-hydroxybenzoate into p-hydroxy-benzoic acid. The enzyme was widely found in molds, and the activity was in following order; Aspergillus>Penicillium>Fungi imperfecti>Mucor>Rhizopus.
The esterase activity could not be observed in strains of yeasts and bacteria tested, except in Bacillus subtilis.
The optimun pH of the enzyme produced by Aspergillus sojae was about 6.0 and the enzyme was stable at pH between 3.2 and 9.0 at room temperature. The activity remained for 15 minutes at 50°C at pH 6.0, while it was inactivated rapidly at 70°C. The property coincided well with that of Aspergillus flavus. These enzymatic properties agreed closely with those of the esterase in shoyu (soy sauce). Therefore, it will be possible to conclude that butyl p-hydroxybenzoate in shoyu is mainly hydrolyzed by the esterase produced by Aspergilli.

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Conditions for separating xylan from straws were examined to obtain an industrial raw material for enzymatic production of xylose. Following procedure was found to be most effective with 90% recovery of xylan. Thus, straw was soaked in 2% NH4OH for 24hrs. at room temperature, in 10% NaOH at 50-60°C for 48hrs., and then filtered. Xylan was precipitated by adding two parts of methanol to one part of the filtrate, and dried under reduced pressure. Crude preparations obtained by this procedure from rice straw (A), bagasse (B), wheat straw (C), and barley straw (D) contained 54.3, 73.5, 73.6, and 76.8%, respectively, of pure xylan determined by Tollens-Krober's method. According to gas chromatography of their acetylated hydrolyzates of those preparations, molar ratio of pentoses of xylans were as follows; xylose 81.7: arabinose 17.6: rhamnose 0.7 for (A), 84.0:15.1:0.9 for (B), 87.5:12.4:0.1 for (C), and 84.1:15.4:0.5 for (D).

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Effect of sodium caseinate or egg-albumin was examined to improve the retention of artificial color to agar jelly. By increasing the concentration of sodium caseinate to 0.4% or eggalbumin to 0.2%, and by lowering pH of jelly to 4.0, the color retention was improved remarkably, although such treatments resulted in, weakening of jelly strength. The color retention of dyes examined was in the following order; rose bengal>erythrosine>phloxine>eosine>sulfonate dyes such as amaranth, acid red, and new coccine.

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Effect of storage conditions was investigated on the viscosity of 20g/l solutions of sodium carboxymethylcellulose and methylcellulose which showed non-Newtonian flow properties. The decrease of their viscosity during storage was accelerated by raising temperature and citric acid concentration, respectively, and by exposure to light.

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In milk containing 50-100ppm. quarternary ammonium compounds (QAC) held at 37°C, multiplication of coliform bacteria were recognized, while that of lactic acid bacteria was inhibited. On application for sanitizing udders and teats of cow, QAC was found to fail to eliminate contamination of milk with coliform bacteria.

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A spot test method with diphenylbenzidine for rapid and approximate estimation of nitrate was examined. On tomato juice, 1ppm. of nitrate-N was found to be detectable by this method, and the obtained values were in good agreement to those by the m-xylenol method of A.O.A.C. and the cadmium-column method proposed by KAMM.

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