Beni-Koji prepared by growing Monascus on steamed rice is an important material for TOFUYO (red soybean cheese)-manufacturing. Optimum conditions for preparation of Beni-Koji were investigated. Two kilograms of steamed rice inoculated with 120 grams of seed-koji(ground in water) was wrapped in a cloth and was incubated at 32°C. After 38hr of inoculation, the temperature of the materials was controlled by mixing them with hand. When the level of moisture was reduced to 30% or less, the koji materials were moistured by water-spraying. By these treatments the growth of the microorganisms and the formation of the koji-pigment were enhanced markedly. Optimum incubation period of the koji making was 150hr after the inoculation of the seed. The highest production of enzyme activities and pigment of the koji was obtained by emproying autoclaved nonglutinous rice. The enzyme activities and the amount of pigment of the koji were not affected by a storagecondition, at-20°C for 12 months. α-Amylase and saccharifying amylase of the koji were alcohol-tolerant, but protease was not.

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A dipping type four-electrode cell was designed and constructed for practical determination of sugar content in Citrus juice by means of our new method based on conductometry.(1)The characteristics of the A. C. four-electrode cell method as conductometry were investigated in concentrate electrolyte solution, such as 0.6M KCl solution, by use of a pilot cell with reproducibly exchangeable current-carrying electrodes. It was suggested that the impedances between probe electrodes show the exact solution resistances, not being affected by current-carrying electrodes and measuring frequencies. (2)On the basis of investigated data, a dipping type practical cell was devised with bright platinum wires of 0.3 and 0.5 mm diameter as probe and current-carrying electrodes, respectively, and the cell constant: θ was 68.1cm^-1. Plastics(polycarbonate resin)was used as cell material in order to make the cell hardier and the cell operation and maintenance easier at practical use. (3)The response time of the practical cell was nearly zero and no change of the measured value was produced for 30 minites successive run. The reproducibility was C. V. =0.02% on repeated runs by the conductivity measurements of 0.6 M KCl solution with the practical cell.

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Effects of emulsifying conditions on the stability, droplet size and viscosity of emulsions prepared by using soybean lecithin were investigated. Better stability was obtained from the emulsion emulsified by a syringe rather than by a Hansen High Performance Disperser. Comparing the stability of the emulsions prepared by three dispersing methods with lecithin in water, Hansen dispereser(A), heating(B)and ultrasonication(C), A was the best and C was the worst. Droplet size decreased with an increase of the lecithin amount added. Droplet of the emulsion prepared by dispersing the emulsifier in oil was smaller than that of the emulsion prepared by dispersing the emulsifier in water. The emulsion became unstable as the emulsifying temperature as well as the standing temperature after emulsification was elevated. Viscosity of the emulsion increased with an increase of the lecithin content and the viscosity of the sample prepared by dispersing lecithin in oil was higher than that of the sample prepared by dispersing lecithin in water. The viscosity of the emulsion decreased with an elevation of standing temperature, and the viscosity behavior depended upon emulsifying method and lecithin content. These results indicate that the emulsion comprised of smaller droplet shows good stability and high viscosity.

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Total lipids extracted from ordinary meat, red meat, skin, liver and viscera (except liver)of horse mackerel, Trachurus japonicus were examined by means of silicic acid column chromatography (SACC), thin layer chromatography(TLC)and gas chromatography(GC). Total lipids were extracted according to the procedure of BLIGH and DYER. The total lipid content(%)in viscera was the highest among five parts above mentioned. Total lipids were separated into neutral and compound lipid fractions by mean of SACC. Ratios of neutral lipid fractions in total lipids were 79.0-96.4%, and the content(%)of neutral lipid fraction in liver was the lowest in five parts. Neutral lipid fractions were separated into 7 kinds of lipids by TLC and a main component was triacylglycerins (TG, 93.6-97.5%). Positional difference of each neutral lipid content(%)was small. Fatty acid composition of total lipids and each netural lipid was studied by GC and about 30 kinds of fatty acids were identified. Main fatty acids of total lipids and each neutral lipid in five parts were 16:0 acid(20.9-23.2%), 18:1 acid(19.0-30.1%), 22:6 acid(10.3-15.9%), 20:5 acid (7.5%), 18:0 acid(5.8-10.1%)and 16:1 acid(6.1-8.1%). In the fatty acid composition of total lipids and TG, 18:1 acid content(%)in liver was rather higher than in the others. On the contrary, little positional difference in fatty acid composition of free fatty acid fraction and sterol ester fraction was recognized.

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The effects of ethanol on the degradation of glycerides and the ethyl esterification of fatty acids in miso during fermentation were investigated by addition of ethanol to miso. Lipase activity in miso, which played the most important role in the changes of lipids resulting in the formation of free fatty acid and ethyl fatty acids, was hardly concerned in the ethyl esterification ratio(the ratio of ethyl fatty acids to all the hydrolyzed fatty acids from glycerides). The ratio was affected definitely by the amount of ethanol in miso. The correlativity between ethanol content(x mg/100g-miso)and the ratio(y%)could be expressed throughout the fermentation period as y=2.079x^0.5-2.070(r=0.986). The degradation ratio(the ratio of degradated fatty acids to total lipids in miso)was high under the condition of high lipase activity or long term fermentation. When the condition of lipase activity and the fermentation period were same, the ratio was affected by the amount of ethanol in miso. Accordingly, the action of yeast during miso fermentation was considered to contribute not only to the aroma formation by production of flavor substances but also to the changes of lipids in miso supplying ethanol as the result of fermentation.

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The mechanisms of the increase of hot water soluble pectin and of the leak of K, Ca and Mg from a crude cell wall preparation(CCWP)during salting of radish root were investigated. The results obtained were as follows: 1)It was found that the content of Na in CCWP during salting increased linearly in relation to the decrease in the contents of K, Ca, and Mg. 2) The increase in the content of Na in CCWP during salting was dependent on the increase in concentration of sodium chloride used. 3)In the hot water soluble pectin increased in CCWP during salting, the Na-content was much increased while the K-content was considerably decreased, showing almost no change in the Ca- and Mg -contents which were decreased in CCWP. From these results, it was presumed that the permeation of sodium chloride into radish root tissues during salting might cause the ion exchange of Na with Ca and Mg of some cell components, especially pectic substance in the cell wall and release Ca and Mg, which give rise to the increase of hot water soluble pectin and the decrease of hexametaphosphate soluble pectin at the time.

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Carboxylic acids contents and composition in miso were analysed with a Carboxylic Acid Analyser. The extract efficiencies of lactic, citric and succinic acids were above 90%, when extracted with 1N HCl. Samples which consist of 43 light yellow, salty miso and 52 yellow red, salty miso were selected at random from those exhibited at The 23rd Exhibition of Miso in Japan. Most of them contained much pyroglutamic and citric acids. The contents of lactic acid varied widely, but the range of acetic acid contents was 50-100mg/100g. The patterns of the detected 15 organic acids had no significant relations to the result of organoleptic evaluation. The analytical method employing a Carboxylic Acid Analyser had an advantage over gas chromatography in the convenience of the preparation of tested samples, good separations of peaks and quantitativeness. There were positive correlations between sum of 4 major organic acids(i.e. lactic, citric, acetic and pyroglutamic acids)and acidity I, and between citrate and the reciprocal of lactate contents. Six strains of Pediococcus halophilus isolated from miso metabolyzed citrate in the miso suspension medium. Moreover, in the experiment using modified Imai's medium, the uptake of citrate and production of lactate seemed active from logarismic stage to stationany stage.

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An internal standard method for the gas chromatographic headspace analysis on the aroma of coffee brew was developed as follows: Five grams of ground coffee was weighed into a 130ml conical flask, and 50ml of the internal standard solution(sec-butanol, 2.5μl/50ml H₂O) was added. The flask was shut up with a silicon rubber having a headspace gas sampling device and incubated at 20°C for 90 min. Zero point five ml of the headspace gas was applied to a gas chromatography. (1)A linear relationship existed between the amount of internal standard and peak area. (2)Ground coffee adsorbed the internal standard in proportion to its concentration. The adsorbed amount was ca. 6%.(3)The reproduci-bilities(for quantitative analysis of the aroma constituents in the headspace gas)ranged from 2.2 to 9.6% based on the coefficient of variation.

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The Ca-content in crude cell wall and the ratio of the 0.4% hexametaphosphate soluble pectin to the total pectin markedly increased in salted radish root prepared by secondary salting process with NaCl containing CaCl₂. Furthermore, the crisp palatability shown as "Hardness value" also increased in the same radish root. Consequently, it was concluded that the increase in Ca-content in radish root by secondary salting process with NaCl containing CaCl₂ introduced much crosslinkages among pectic substance molecules, and resulted in the improvement of crisp palatability.

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A mix containing 42% wheat flour, 20% corn starch, 20% sucrose, 11% soy protein isolate, 6% sodium caseinate, and 1% NaCl was texturized in a corotating twin screw Creusot-Loire BC-45 extruder. Temperature and pressure of the mix measured just before the die, and distribution of residence time measured using erythrosin, were reported as a function of water content, feed rate, screw rotation, and barrel temperature. Under usual operating conditions, 13% water, 40 kg/hr, and 80 rpm, the mix progressed without bachmix along the first 400mm of screw length in 10 sec; in the last 150mm section, where the reverse screw element was located, the melted mix remained from 25 to 70S, at about 200°C. Sucrose hydrolysis during extrusion, as determined by the invertase-glucose oxidase method, varied from 2 to 10% of initial sucrose. Loss in FDNB-reactive lysine caused by Maillard reaction was from 0 to 44%, depending mainly on temperature and water content, and not on screw rpm; lysine loss decreased when water content increased from 13% to 18%, even when the barrel temperature was increased so as to keep the temperature of the flour mix constant. Molar ratio of sucrose to lysine loss was always≥1.2. Decreasing the pH of the flour mix with citric acid or glucono-δ-lactone enhanced the loss of FDNB-reactive lysine. Severe conditions of extrusion-cooking also caused a decrease in cystine and arginine.

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