Microorganisms used in an industrial scale process of pot vinegar were separated and grouped into lactic acid bacteria, yeasts and acetic acid bacteria. Specific microorganisms belonging to each group were further classified and identified. Changes in the microbial flora of pot vinegar were examined during the manufacturing process. The results were as follows. Two hundred and thirty strains of lactic acid bacteria were separated and identified at 1, 5, 10, 20 and 30days after mash was prepared. Lactobacillus plantarum was found to grow mainly for 5 days after mash preparation. L. casei subsp. casei population increased starting on the 10th day to the 20th day. At 30days after mash preparation, L. coryniformis subsp. coryniformis accounted for 68%, L. sake for 20% and L. brevis for 12% of the lactic acid bacteria. Yeast strains were identified at 5, 10, 20 and 30 days after mash preparation. From the 110 strains identified, all strains were found to be Saccharomyces cerevisiae, regardless of sampling day. Strains of acetic acid bacteria were identified at 45, 60, 75, 90 and 120 days after mash preparation. In the 150 strains identified, Acetobacter pasteurianus and A. aceti occupied 65-81% and 18-35% of the population, respectively. From these results, with regard to the microorganisms on the manufacture of pot vinegar, changes in the microbial phases were revealed as follows. L. plantarum and L. casei lactic acid bacteria grow just after mash preparation, producing about 1% lactic acid. S. cerevisiae yeast increased because of the lactic acid present. After alcohol production, floating rice koji touching the pot began to fall gradually. A. pasteurianus was then the main acetic acid bacteria with some A. aceti present, promoting acetic acid fermentation.

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The stabilization of 6-methylthiohexyl isothiocyanate in Wasabi (Wasabia japonica Matsum.) by addition of antioxidants and some other compounds was studied. Addition of 1% each of sodium thiosulphate, methionine, acetic acid, and ethanol did not show any effects on stabilization of 6-methylthiohexyl isothiocyanate in wasabi, whereas addition of 1% of α-tocopherol or a rosemary extract resulted in significant stabilization of it. Addition of α-tocopherol together with ascorbic acid induced a synergistic effect on stabilizing not only 6-methylthiohexyl isothiocyanate but also the allyl isothiocyanate.

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In order to remove dissolved oxygen from liquid food, ascorbate oxidase (AO) was covalently immobilized onto ethylene-vinyl alcohol copolymer (EVOH) film. Maximal activity was observed at pH 6.0, 30°C (1.14mU/cm²). The immobilized AO still retained a higher residual activity than free AO under practical conditions; at pH 4.0 corresponding to citrus juice, 10°C and 60°C, the residual activities were 47.8%, 91.3%, and 49.4% whereas those of free AO were 3.1%, 63.3% and 0%, respectively. When the AO immobilized EVOH film was directly in contact with 2.5mM L-ascorbic acid in 10mM citrate buffer solution (pH 4.0), more than 85% of dissolved oxygen was removed within 4h. In addition, flavors (d-limonene, linalool, and citral) in the solution were successfully preserved from the oxidative deteriorations; for d-limonene, the residual ratio (71.6%) with AO immobilized EVOH film was 2.5-fold that with non-immobilized one (29.0%) after 28 days' storage.

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Meat consists mainly of water, protein and fat. The thermal conductivity of meats varies depending on the composition. For measurement of the thermal conductivity, there are two methods, i.e., steady-state method and non-steady-state method. Minced lean meat (beef, pork or chicken) was mixed with different amounts of fat, and the thermal conductivities of these test samples were measured in the temperature range of 5 to 60°C, using a plane heat source method and a heat wire method. In the plane heat source method the thermal conductivity slightly increased with temperature in proportion to the increase of meat sample, while the heat wire method was little or not affected by the temperature. From a practical standpoint, the heat wire method seems to be more convenient than the plane heat source method for the determination of the thermal conductivity of meats. The relations between the moisture content, fat content and thermal conductivity were shown exponetial proportion with positive or negative, respe ctively. The empirical equations for the thermal conductivity of beef were as follows: where, λ_p and λ_n are the thermal conductivities (W/m·K) by the plane heat source method and the heat wire method, respectively, and x₁ represents the moisture content (%) and x₂ is the crude fat content (%).

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A large amount of ethanal and a small amount of acetone were generated from mackerel muscle homogenates by heating in the presence of potassium bromate. Ethanal generation was observed when pH of the homogenates was below 7 and distillation temperature was more than 70°C. Addition of hydrogen peroxide generated more ethanal than that of potassium bromate. Addition of sodium hypochlorite to mackerel muscle generated ethanal, isobutanal and 2-methylbutanal. By addition of potassium bromate, a large amount of ethanal was generated from fish with red-colored flesh such as mackerel, sardine, yellowtail, tuna and so on, though no ethanal from fish with white-colored flesh such as plaice and sea bream, tuna (dark muscle), egg, milk and so on. Causative substances of ethanal generation were considered to be water soluble, but no ethanal generation was observed from amino acids, carbohydrates, organic acids, nucleotides, alcohols and fatty acids by addition of potassium bromate and heating. These findings suggest the existence of other unknown substances as the causatives of ethanal generation. All 11 spices tested suppressed ethanal generation from mackerel muscle. Reductive agents such as sodium sulfite, sodium bisulfite and maltol also suppressed ethanal generation. However, antioxidants such as butylated hydroxytoluene and butylated hydroxyanisole, cyclodextrins, and amino-carbonyl reaction inhibitors such as cysteine and calcium chloride had no suppressive effect on ethanal generation. Ascorbic acid enhanced ethanal generation.

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Time series analysis was performed on ripening process of picked plum 'OoishiWase' fruit by near infrared (NIR) spectroscopy. Accompanying ripening after picking, base lines of NIR spectra of intact fruits were shifted up remarkably. It was suggested that these shift up of spectra was caused by an increase of transmittance of NIR ray into the intact fruit which was attributable to loosening of middle lamella in tissue structure. On the other hand, an absorption peak at vicinity of 1410nm became larger regardless of shift up of NIR spectrum. Therefore, 1410nm was considered to be a key wavelength to evaluate ripening after picking of plum fruit. Ripening of plum fruit affected the measurement of soluble solid (^°Brix), acidity (%) and hardness (kg) values of the fruit by NIR spectroscopy and increased the standard error of prediction (SEP) of measurement by NIR spectroscopy to analyze fruits with different ripeness after picking. By using a calibration curve based on samples with different ripeness, accurate measurement by NIR spectroscopy was successfully performed. It was considered that the principle of measurement of hardness in plum fruit by NIR spectroscopy was based both on shift up of base line of NIR spectrum and on changes of chemical components in AIS.

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The effect of ultrasonic wave on promotion of food drying was examined. A transducer used for this experiment was of the bolt-clamped Lagivin type (19.5kHz) with an exponential horn. A vibration plate (3mm thick, 154mm wide, 434mm long) was fixed to the front end of the horn. This was set in a drying chamber (180mm high, 200mm wide, 750mm long). Walleye pollack surimi was used as a test sample. The surimi sample, spread in a thin layer (3mm thick), was dried at 20-50°C by ultrasonic irradiation. The following results were obtained. (1) The surimi sample was dried at 40°C at the sound pressure level of 153.5dB at an air flow rate of 1.6-2.8m/s. The drying rate without ultrasonic irradiation increased linearly with an increase in the air flow rate, while under ultrasonic irradiation it also increased linearly depending on the air flow rate and at an air flow rate of 2.8m/s it increased more rapidly. (2) At sound pressure levels greater than 150dB (particle velocity 150cm/s), the increase in drying rate became significant. (3) The surimi sample was dried at 20-50°C at the sound pressure level of 155.5dB (particle velocity 300cm/s) with the air flow rate of 2.8m/s. The drying rate increased from six times (30°C) to 2.5 times greater (50°C) compared to that without ultrasonic irradiation.

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A new technique of supercritical carbon dioxide (SC-CO₂) treatment, micro bubble SC-CO₂ method, was applied to extraction of limonoids. This method could increase the concentration of SC-CO₂ in sample solutions rapidly, so that limonoids were extracted effectively compared with conventional technique. Juice (sample A) and seed extract (sample B) of Natsudaidai were treated at 25MPa, 35°C. The flow rate of CO₂ was 4g/min. The yield of limonoids was significantly higher than those extracted by conventional SC-CO₂ method. When the extraction was carried out for 30min, the extraction yield of limonoids in sample A and sample B were 92.5% and 42.4%, respectively. When methanol was added as an entrainer, the yield of sample B was increased up to 73.2%.

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Yakifu shrinks when baking time is not enough to expand the structure. Therefore, expanded structure of yakifu during baking was observed with a scanning electron microscope. Expansion of yakifu started from a part touching to the floor of an oven owing to the heat transferred from the floor, and the expanded structure was fixed through the drying of the surface by the heat from ceiling of the oven.

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Using a bench-scale Continuously Stirred Tank Reactor, enzymatic saccharification of Okara (a byproduct of tofu) was conducted in order to investigate the product inhibition and to evaluate the process kinetically. With the increase in reducing sugar, a rapid decrease in the rate of saccharification or solid degradation was observed, and the relationship between the solid degradation ratio and the apparent saccharification rate was presented experimentally by a quadratic equation. By applying a Michaelis-Menten equation for competitive inhibition, apparent kinetic parameters which describe the effect of inhibition quantitative were determined.

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Some kiwifruit growers notice that kiwifruit markedly differs in the sensitivity to ethylene treatment for artificial ripening, depending on the origin. However, it remains to be scientifically demonstrated whether it is true. Therefore, in order to study the variation in the sensitivity to ethylene, 26 samples of kiwifruit were collected from the main kiwifruit-producing districts in all of Japan and were held for ripening in an ordinary commercial tray with an ethylene generator at 15°C. Eighteen out of the samples, which seemed to be sensitive to ethylene treatment, softened and ripened in the presence of 10-20 μl·l^-1 of ethylene produced from the ethylene generator, but the rest (8 samples), less sensitive, didn't ripen and produce the ripening-related ethylene. The reduced sensitivity of the samples to ethylene was quite reproducible even under the different conditions with doubled quantity of the ethylene generator at 20°C. These results suggest that such less sensitive kiwifruit requires more drastic ethylene treatment conditions for ripening.

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An investigation was made on the factors affecting the state of rice grain of canned cooked rice utilized in a sense of drinks. Among 10 kinds of rice varieties, Hirakou No. 102 was in the most satisfying with respect to non-stickiness, fluidity and morphological stability. Using seasonings and soaking treatments under various conditions, it was investigated how to keep the favorable properties of rice grain when cooked with milled rice at a concentration of about 10%. In the case of soaking treatment in 1% solution of citric acid for 3min., the most satisfactory results were obtained within the range of pH 4.0-4.5. Furthermore, a time course examination for 60 days revealed that the good conditions of cooked rice could be kept even in a hot vendor at 55°C and similar results were also obtained by the treatments with other organic acids. Since these conditions protected rice grains from swelling and resulted in a decrease in loss of viscous materials in the grain, which appeared to these properties with respect to fluidity, non-stickiness and morphological stability. In addition, the formation of damaged grains due to acid degradation seemed to have been suppressed at a minimum level. Correlation was recognized between the state of rice grain and the degree of alkaline degradation.

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Influence of nitrogen gas added to hydrogen on hydrogenation of corn oil has been evaluated. Hydrogenation of corn oil was conducted in a 12l loop reactor with reduced nickel catalyst. Nitrogen gas influenced its reaction rate as previously reported on soybean oil hydrogenation with inert gases added to hydrogen gas. When hydrogenation pressure was greater than 2.94×10⁵Pa, the reaction was accelerated with increasing nitrogen pressure. The reaction rate decreased with increasing nitrogen pressure at hydrogen pressure below 1.96×10⁵Pa. Hydrogen pressure at which the added nitrogen did not affect the reaction was determined 2.45×10⁵Pa Which was higher than the hydrogen pressure of soybean oil hydrogenation. No marked influence of nitrogen gas was observed on trans-isomer formation. The results indicated that effect of added nitrogen on the reaction depended on fatty acid composition of oil to be hydrogenated. The experimental reaction rate equation derived in the previous paper was also adopted in this study. The equation was confirmed to express well the influence of nitrogen gas added to hydrogen on hydrogenation of corn oil.

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This investigation is planned to make clear the mechanism of Yakifu expansion. First of all, relationships between baking conditions and expanded specific volume of yakifu were studied. Yakifu expanded when baked at the temperatures of oven-floor higher than 150°C. Higher the temperature was, larger the volume was. If the temperature of ceiling is the same as or lower than that of floor, expanded yakifu shrinks at once when stopped baking. Therefore, the temperature of ceiling was always set at 30°C higher than that of floor. Heat from the floor was transferred to cuts of gluten-dough and moisture involved in them started to vapor, forming air cells surrounded by gluten walls. Air cells formed honeycomb structure in the cuts of gluten-dough, and finally a top layers of the cuts were built up. Heat from the ceiling is important to promote drying to fix the structure of yakifu. Watering the cuts just before starting baking largely increased expanded specific volume of yakifu with increasing the amount of water.

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The effects of fruiting direction and fruits weight on mineral components of apple fruits were investigated using Fuji cultivated at Morioka Branch, Fruit Tree Research Station in 1979. The 9 mineral components were measured, i.e. sodium, potassium, magnesium, calcium, iron, manganese, copper, zinc and phosphorus in individual apples from the single tree. Mineral content or mineral content in ash were affected by fruiting direction in all minerals except sodium. The fruit weight and brix degree of apple fruits in the west side were significantly lower than those in other sides. The potassium content of apple fruits in the west side was significantly higher than those in other sides. Ash and sodium, potassium, magnesium, iron and phosphorus showed a positive correlation in all using 40 apples. In mineral content, positive correlations were observed in more couples of minerals in north side than in the other sides. On the other hand the mineral content in ash positive orrelations were those in west side than in the other sides. Calcium and manganese showed a positive correlation in all sides. The effect of fruit weight on the composition of mineral was also considered using 40 apples. Mineral content was not affected by fruit weight in all minerals except manganese. Brix degree in the larger grades was significantly higher than that in smaller ones. The size of apples in the south side was largest and that in the west side was smallest. The concentrations of manganese and zinc in the larger grades were significantly lower than those in the smaller ones.

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Natural preservatives, especially those effective in the presence of NaCl, are desired. To develop such a natural preservative, we examined the killer effect against Z. rouxii of the culture filtrate of Kluyveromyces thermotolerans IFO 1778 strain. This strain was shown to have killer activity against Z. rouxii in the presence of more than 4% NaCl. Its killer activity increased with the increase of NaCl concentration. Killer toxin of IFO 1778 was active in the range of pH 2 to 6 (optimum pH was 4). Killer activity was lost by heating at 40°C for 15min. Polyols had effect to stabilize killer activity. One percent conc. of freeze-dried culture filtrate of koji medium inhibited the growth of Z. rouxii and delayed fermentation. While killer activity was not affected by proteases, it was increased by cellulase treatment.

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Experiments were conducted to investigate the effect of supplementation of different sources of vitamin D on the transfer of vitamin D to the egg yolk. Vitamin D₂-fortified shiitake, pure vitamin D₂ and pure vitamin D₃ were used as a source of vitamin D. Experimental diets contained each source of vitamin D at the level of 500μg/kg as the amount of vitamin D in the basal diet. Laying hens (White Leghorn) were divided into three groups of five birds each and fed the experimental diets for 14 days. The initial contents of vitamin D₂ and vitamin D₃ in the egg yolk were undetected and 0.05μg/g, respectively. At the end of the experiment, vitamin D₂ and vitamin D₃ contents (μg/g) in the egg yolks were as follows: 0.326, 0.080 on the shiitake diet; 0.277, 0.055 on the vitamin D₂ diet and undetected, 0.494 on the vitamin D₃ diet. The transfer ratio of vitamin D (total amount of vitamin D₂ and vitamin D₃) to the egg yolk on the shiitake, vitamin D₂ and vitamin D₃ diets were 10.9%, 8.8% and 12.7%, respectively. The transfer ratio of vitamin D₃ tended to be higher than that of vitamin D₂. The content of 25-OH-D3 in the egg yolks on the vitamin D3 diet increased three-fold during the experimental period, and 25-OH-D₂ was detected in the egg yolk on the shiitake diet and vitamin D₂ diet. However, the content of 25-OH-D₂ in the egg yolk was significantly lower than that of 25-OH-D₃. There was no effect of the different sources of vitamin D on the performance, egg shell quality and concentrations of calcium and phosphorus in the plasma of laying hens.

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Anthocyanin pigments (shiso AN) were extracted from the purple leaves of Perilla ocimoides L. var. crispa (Japanese name, "shiso") and were examined regarding the anthocyanin composition and their stability to heating, ultraviolet (UV)-light irradiation, and effects under the coexistence of additives such as polysaccharides and glycyrrhizinate (GR). The results obtained were as follows. 1)By means of high-performance liquid chromatography (HPLC) and HPLC-mass spectrometry (LC/MS) analyses, the structures of three isolated anthocyanins from shiso AN were presumed to be cyanidin 3, 5-diglucoside, cyanidin 3-(6-p-coumarylglucoside)-5-glucoside; shisonin and cyanidin 3-(6-p-coumarylglucoside)-5-(6-malonylglucoside); malonylshisonin, while the remaining components have not been identified yet. 2)A major pigment estimated to be malonylshisonin in shiso AN was shown to be the most labile under heating and UV-light irradiation. 3)Addition of polysaccharides essentially did not increase the absorbance (ABS) of shiso AN solution as compared with that of non-addition; however GR addition increased the ABS. 4)When shiso AN solution containing added polysaccharides was heated to 100°C for 8h (heating), the sample with alginate addition was stabler than that the non-addition sample. While under UV-light irradiation for 8h (UV), the fading ratio of every polysaccharide containing shiso AN was lower than that of non-addition samples. 5) Shiso AN solution containing added GR decreased in fading ratio compared with the non-addition sample under both heating and UV conditions.

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