"Sobatsuyu" (Japanese noodle soup) is prepared by blending of" Kaeshi" (mixture of soy sauce, sugar and Mirin) and a hot water extract of dried bonito. The quality of "Sobatsuyu" made from "Kaeshi" aged under different conditions in our laboratory was investigated. Flavor of the "Kaeshi" sample (sample A) which was prepared by aging in a opened vessel was superior to the sample prepared in a closed vessel (sample B) by sensory analysis. Evaporation of water and alcohol was observed in the opened system (sample A) during storage, while not in the closed system (sample B). Coloring occurred in sample A during storage but not in sample B. This coloring was considered not to influence sensory improvement, since sensory analysis revealed that "Kaeshi" stored in nitrogenous atmosphere was also as good as that in air. A distinct increase of microorganisms was not observed in both samples A and B. Some volatile components decreased in sample A in contrast to sample B during storage. These experiments suggest that a decrease of certain compounds in physical phenomena such as evaporation plays an important role for improving "Kaeshi" quality during storage.

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Papaya was wrapped with a polyethylene film and artificially damaged by vapor heat treatment before use. As a result, the vole of polygalacturonase (E.C. 3.2.1.15) (PG), softening enzyme, in the damage of papaya during vapor-heating was observed. Three electrophoretically different PG isozymes, namely PG-1, PG-2 and PG-3 were found. PG-2 and PG-3 were notably involved in the softening of papaya. The molecular weights of polyuronide changed by decomposition or dissolving by enzymes such as PG, etc. In consequence, the molecular weight of polyuronide decreased from 990000 to 100000 in both the normal fruits and the non-defective parts of damaged fruits. It proved a normal progress of ripening was occured in proportion to growth of fruits. However, no decrease of molecular weights was observed in the defective part of the damaged fruits. This fact led to an assumption that non-ripening of fruits may attribute to incomplete degradation of polymeric galacturonic acids.

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The soluble proteins and the protease activity in kiwifruit during development were examined by electorphoresis and gel filtration. (1) The protease activity, soluble protein contents and the yield of acetone powder from kiwifruit increased up to the 16th week after anthesis. A high positive correlation was found between the protease activity and the yield of acetone powder with three cultivars of kiwifruit. (2) The electrophoretic patterns of soluble proteins of 3 cultivars showed that proteins around 60kDa, which were slightly observed in the 4-12th weeks after anthesis, increased after 16th week. It was also showed that some bands around 30kDa and below were apparently observed during the development of Bruno fruit, but in other samples tended to decrease. (3) Gel filtration chromatography of the crude enzyme fractions at the 12th and the 24th week after anthesis did not show significant differences. The highest activity of protease was eluted with cytochrome c. (4) The highest protease activity in a gradient polyacrylamide gel was found in a section of around 13kDa protein. (5) The ripening of kiwifruit was accelerated by ethylene treatment, and the protease activity in the fruit was slightly declined.

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Acceleration of chemical reactions in the frozen state has become of interest in recent years because of its unique characteristics. To give a theoretical intepretation for the acceleration mechanism of such reactions, a new equation was derived. The equation was essentially based on the Arrhenius formula and the Heiss formula, and derived by taking into account of the concentration effect caused on freezing a solution. For calculation, the kinetic data obtained from the acid-catalyzed deformilation of N-acetyl-N'-formyl-Lkynurenineamide (YAMASAKI et al., J. Biochem., 80, 1287 (1976)) were used. The results clearly indicated that the calculated first-order rate constants at various temperatures were in good agreement with the experimental data. The acceleration of the deformylation of N'-formylkynurenine in the frozen acidic solutions can be interpreted as being due to the concentration of the reactants in the liquid region in ice crystals.

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(1) Shredded Licorice roots (Glycyrrhizaglabra L. var. glandulifera in Afghanistan) were extracted with hot water (88-90°C). (2) The yield of Licorice Extract from Licorice Roots was 33.1% (W/W). (3) Volatile components obtaited from the Licorice Extract by simultaneous distillation-extraction were investigated and indentified by capillary GC, GC-MS and Kovats retention indices. Identified new components in Licorice Extract were 1 aldehyde, 3 ketones, 3 acids, 1 phenol and phenolic ether, 2 pyrroles, 3 pyridines and their derivatives, 3 furans and 3 hydrocarbons. (4) The aroma quality was improved when the Licorice Extract was heated at 110°C for 30min.

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Soluble dietary fiber (SDF), insoluble dietary fiber (IDF) and inorganic elements in wheat short were determined, and relations among them were discussed. Furthermore, relation between SDF and inorganic elements was studied by gel-chromatography. Dietary fiber was determined by the enzymatic and gravimetric method by Prosky, and inorganic elements were analyzed by atomic absorption spectrometry and inductivity coupled plasma (ICP) emission spectrometry. The filtrate in IDF filtration was separated by gel-chromato- graphy, and carbohydrate, protein and inorganic elements in each fraction were determined. Results were as follows: (1) Contents of IDF in wheat short were 15-16%, and those of SDF were 4.8-6.5%. (2) Contents of Fe, Zn and Cu in IDF were 54-73%, 27-28% and 21-25% of those in wheat short, respectively. It suggested that those elements in IDF would not be absorbed into human body. (3) Gel-chromatography of the filtrate in IDF filtration suggested that most carbohydrate was monosaccharide, produced by enzymatic procedure. Retention time of inorganic elements in the fraction of fitrate in IDF filtration was obviously different from that of SDF (polysaccharide). These results suggested that inorganic elements could be hardly adsorbed by SDF.

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The activity of an enzyme degrading rutin in tartary buckwheat (Fagopyrum tataricum) seeds and common buckwheat (Fagopyrum esculentum) seeds was compared. HPLC analysis showed that rutin was contained 100 times higher in tartary than in common buckwheat flour. On addition of water to tartary buckwheat flour, most of rutin decomposed to quercetin rapidly. The crude rutin degrading enzyme extracted with 0.02M acetate buffer (pH5) from tartary buckwheat showed 680 times higher activity than that from common buckwheat. The crude enzyme did not act on quercitrin and naringin. The crude enzyme from tartary buckwheat was also accompanied by little β-glucosidase and a-rhamnosidase activities. From these results, it was suggested that this enzyme is specific for rutin. This enzyme was unstable above 70°C, below pH3 and above pH7, and inactivated by protein denaturants.

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The successive treatments with acid and alkali were successfully applied to disintegrate the cotyledon tissues of soybeans as follows. One gram of dry soybeans was immersed at frst in 10ml of 0.2M hydrochioric acid at 35°Cfor 24hours. The soybeans were then washed with water, dehulled, separated into two cotyledons, and washed again with water. The cotyledons were finally stirred in 10ml of 0.1M sodium hydroxide solution by a magnetic stirrer at room temperature for 2hours. The treatment with alkali resulted in the complete disintegration of cotyledon tissues and the separation of cotyledon cel1s. When the acid-treated cotyledons were treated in dilute sodium hydroxide solutions or buffer solutions of various pH values until the tissues were disintegrated completely, increasing pH caused the decrease in the yieid of cotyledon cells, as well as the decrease in the stirring time required for the complete disintegration of the tissues. It was assumed that the low yield of cotyledon cells at higher pH may be caused by the solubilization of components to alkaline solutions or by the partial damage or rupture of cells.

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Suppression of degradation of ATP-related compounds in fish flesh during cold storage by several salts was demonstrated by using HPLC. Contents of the nucleotides such as ATP, ADP, AMP and IMP were 0.28, 0.27, 0.41 and 0.28μmol/g, respectively in the ground flesh of non-salted Alaska pollack frozen surimi, and those of inosine (HxR) and hypoxanthine (Hx) were 0.57 and 0.38μmol/g. The total nucleotides decreased during storage at 4°C, while HxR or Hx increased in return. An addition of 0.5M salts suppressed the degradation from IMP to HxR during storage, in the order of CaCl₂>MgCl₂>NaCl=KCl. On the other hand, the total nucleotide content in the ground flesh of sardine was 11.2μmol/g, in which IMP comprised 86%. The degradation of IMP during storage was also suppressed by 0.5M salts, in the order of NaCl =KCl>CaCl₂. It was presumed that these salts suppressed the degradation from HxR to Hx in addition to that from IMP to HxR, since HxR was considerably accumulated during storage in the presence of the salts.

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"Sobatsuyu"(Japanese noodle soup) is prepared by mixing "Kaeshi"(mixture of soy sauce, sugar and Mirin) and a extract of dried bonito. The influences of growth of microorganisms on the quality of "Kaeshi" were investigated."Kaeshi" inoculated with various microorganisms were incubated for several days at 30°C. Viable cell counts of Pediococus halophilus and Aspergillus oryzae decreased and those of Lactobacilus spp. remained approximately constant during incubation. On the other hand, the counts of Zygosaccharomyces rouxii and Z. rouxii (film-forming) increased with incubation time. With the growth of Z. rouxii, the sugar contents of "Kaeshi" decreased, but the alcohol contents increased. By sensory analysis, the growth of Z. rouxii had no effect on the quality of "Kaeshi", but Z. rouxii (film-forming) gave a bad effect.

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Paper electrophoresis was examined for analysis of five 5'-ribonucleotides and the corresponding ribonucleosides as model compounds of food components. Paper electrophoreses were carried out at 700V/35cm for 1h on four types of Toyo Roshi filter paper with 0.1M boric acid-0.05M triethylamine buffer (pH 9.5) or 0.1M triethylammonium bicarbonate buffer (pH 7.5). The UV-absorbing spots on the electrophorogram were extracted with water and the UV absorption spectra were measured at pH 7.0. Correction of UV absorption on contaminants in filter paper itself was performed as follows: The real absorbance of the extract at the desired wavelength was obtained by subtracting the product of the correction factor and the absorbance measured at 320nm without nucleotidic absorption band from the measured absorbance. This factor was obtained as the ratio of absorbance of the extract of filter paper itself at the desired wavelength to that at 320nm. Recovery of a sample was estimated as the percentage of real maximum absorbance of the extract to that of original solution. This method gave reproducible recovery values of more than 92% for each sample from all the filter paper after electrophoresis. The percentages of respective components in total absorbance after separation by paper electrophoresis from the mixture solution of a 5'-nucleotide and the corresponding nucleoside were almost the same (errors were less than 1%) as those in the original mixture solution.

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Alternaria alternate β-galactosidase was purified and its characteristics were examined. Water extract of crude enzyme obtained from wheat bran culture was purified by salting-out of ammonium sulfate, and by column chromatographies of Sephacryl S-200, DEAETOYOPEARL 650M and Hydroxyapatite. At the final stage, the enzyme was purified to 174-fold activity in comparison with its crude extract and shown unique activity band. Its character were followings; molecular weight was 125000, optimum reaction pH was 4.0-4.5 for ONPG and 5.0-5.5 for lactose, and its stability was kept in the pH range 4.0-8.5. Optimum reaction temperature was about 60°C and heat stability was below 55°C in 1 hour. Km values were indicated respectively 1.56mM for ONPG and 13.9mM for lactose. Inhibitory actions were not observed in the tested reagents.

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Steam stripping of roasted coffee is applied to the production of soluble coffee in an attempt to itcrease the aromatic quality of the product. This practice, however, has two drawbacks which partially negate the benefits. Firstly, the addition of the aroma condensate to the coffee extract results in dilution which adversely affects aroma retention during drying. Secondly, the aromatics derived from Robusta coffee sometimes reduce consumer acceptance of the soluble coffee product. Two methods were investigated in this research as a route to overcoming these difficulties. Distillation of the steam aroma was examined as a means of concentrating and rebalancing the aromas. "Partial Steaming", wherein only the Arabica portion of the blend is stripped to recover aromas, was also explored. Products made by these techniques were evaluated by our expert panelists and ordinary consumers. Products containing fractionated steam aroma showed an overall improvement in quality and a reduction in sourness and harshness. The "Partial Steaming" process enabled us to enhance desirable Arabica coffee characteristics in the soluble coffee while reducing Robusta flavor noths. Consumer testing of samples prepared using these methods confirmed that both techniques resulted in an improvement in overall product preference.

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Linamarase produced by Aspergillus oryzae SAl was purified 193-fold by ammonium sulfate fractionation, Sephadex G-25, DEAE-cellulose and Ultrogel AcA 44 chromatographies. The enzyme has K_m values of 2.l2mM and 0.53mM with respect to linamarin and ρ-nitrophenyl-β-glucoside, respectively. The molecular size of the enzyme was found to be 100000 daltons by Ultrogel AcA 44. The enzyme had optimum activity at pH5.5, and it was found to be very stable at 40-50°C for 50 minutes. It was competitively inhibited by gluconoδ-lactone with a K_i of 0.1mM. Isoelectric focusing showed the presence of three active forms of isomers at pI values of 8.85, 7.30 and 6.55.

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The fatty acid compositions of lipids in the mycelia of nine species of Aspergillus fungi were examined by capillary column gas chromatographic analysis. The predominant fatty acids of the lipids in Aspergillus fungi were 15:0, 16:0, 17:0, 18:0, 18:1 (n-9), 18:2 (n-6), 18:3 (n-3) and 24:0. All the samples contained high levels of 18:1 (n-9) and 18:2 (n-6), and the total amounts of these two fatty acids comprised 64-80% of the total fatty acids. The fatty acid compositions of the lipids in Aspergillus fungi were similar to those of vegetable oils such as soybean, peanut and cottonseed oils.

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