Amino acids of water soluble fraction (W-S) and n-butanol soluble fraction (Bu-S) from non-salted and several kinds of soybean miso were detertmined in order to investigate bitterness in non-salted soybean miso. (1) W-S of several kinds of soybean miso, contained a lot of free and bound types of hydrophilic amino acids such as glutamic and as partic acid, in contrast to a small quantity of free and low level of bound types of hydrophobic amino acids such as leucine, isoleucine, phenylalanine and valine. (2) In Bu-S a large quantity of hydrophobic amino acids were detected in the order of leucine> phenylalanine>isoleucine>valine, however the ratio of bound type hydrophobic amino acids was low. (3) In Bu-S of several kinds of soybean miso was detected 1-14m mol/100g of free type tryptophan which was concentrated 5-10 times in W-S. (4) In Bu-S, the free type of hydrophobic amino acids (mol%) was concentrated to about 3 times, those bound type to about 4 times in W-S. (5) From these results, it was estimated that strong bitterness of non-salted soybean miso and weak bitterness of soybean miso were attributable to a large quantity of free type and low ratio of bound type of hydrophobic amino acids such as leucine, isoleucine, phenylalanine and valine and in addition, free type of tryptophan.

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Comminuted pork cured under conventional or aseptic condition, and sausage prepared by heating the cured pork were studied for the changes in fatty acid composition of phospholipids (PL). Compared with curing without nitrite, curing with nitrite produced significant changes in the fatty acid composition of PL in both comminuted porks cured under conventional and aseptic conditions. C_20:4 and C_18;2 contents of PL, phosphatidylcholine and phosphatidylethanolamine fractions decreased with curing period. Peroxidizability index also decreased with these changes. Heat treatment caused more considerable changes in the fatty acid composition of PL in the comminuted pork cured under conventional conditions than in the pork cured under aseptic conditions. It thus appears that the changes produced by heat treatment in the fatty acid composition of PL may be associated in part with the microbial population. With comminuted pork cured under aseptic conditions with nitrite, heat treatment decreased the polyunsaturated fatty acid (PUFA) contents, particularly C_20:4 and C_18:2, when compared with the pork cured without nitrite. The present study has also shown that heat treatment accerelated the reaction of nitrite with PUFA of PL in meat.

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Protein dispersion spinnability, as an indicator of amenability to spinning, was examined for muscle proteins as well as for soybean protein and milk casein, whose fiber formation has beend escribed by many researchers, by a test method specially devised to measure the tenacity of dispersion columns raised by a metal cylinder. Spinnability was observed in soybean protein dispersions in the rather narrow range of 12-15% concentration, pH 12, and 40-50°C, and in milk casein dispersions in the wider range of 20-40% concentration, pH 8-12, and 30-50°C. Dispersions of chicken muscle, ox liver and carp muscle proteins alone showed no spinnability at any protein concentration, pH or temperature, but all of them showed spinnability at 10% protein concentration, pH 12, and 40-50°C, following the addition of a free fatty acid having a carbon number of 10 or more, sodium dodecyl sulfate, or sodium dodecylbenzene sulfonate by 10-20% per protein. Cationic and nonionic surfactants had no effect.

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This paper was undertaken to investigate the reason for the immersing of vegetables to hot water for a short time before fermentation in case of manufacturing fermented pickles. When the vegetables were treated with moderate heat at 50°C, Gram negatives were destructed more rapidly than Gram positives. Pseudomonas fluorescens was particularly destructed to 10^-2 after heat treatment at 45°C for 15 minutes. From the leakage of 260nm absorbing substances, orsinol reactive materials and carbohydrates from heated cells of Gram negatives, it was sugested that the damage to the cell membrane and degradation of ribonucleic acid took place within the moderate heat (45°C) treated cells. The viable cells of Gram negatives which were able to reproduce on modified plate count agar medium containing sodium chloride by moderate heat treatment were decreased with increasing concentration of sodium chloride. These results suggested that the salt tolerance of them were lowered by heat treatment. Since Gram negatives containing nitrite producing bacteria contaminating vegetables were easily destructed by moderate heating, nitrite production was depressed at anearly stage of fermentation.

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In order to elucidate the role of eight taste-active components, glycine, alanine, glutamic acid, arginine, AMP, sodium, potassium, and chloride ions, in producing the characteristic taste of the adductor muscle of scallop (Patinopecten yessoensis), a series of omission tests was conducted with a simplified synthetic extract composed of them. The contribution of glycogen was also evaluated by adding it to a reconstructed extract containing thirty-three components. Results obtained are summarized as follows. (1) Glycine contributed greatly to sweetness, one of the characteristic taste of scallop, and to elevate overall preference. Alanine also provided the extract with sweetness, although far less than glycine. Arginine, a bitter amino acid, imparted overall preference rather than bitterness. Glutamic acid and AMP gave umami and increased continuity, complexity and fullness as well. The overall preference was also improved greatly by them. Sodium, potassium and chloride ions were shown to have an important role in elevating continuity, complexity, fullness and mildness. Among the three ions, the contribution of chloride ion was the most remarkable. (2) The principal-component analysis revealed that the palatability of scallop was closely related to umami, continuity, complexity, fullness and mildness. (3) Glycogen enhanced continuity, complexity, fullness, mildness and thickness.

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Myosin B, myosin and actin were polymerized and gelled by Ca²⁺-independent transglutaminase (B.T.G.) derived from a microorganism (Streptoverticillium). The concentration of B.T.G. required for gelation of myosin B was lower than that for myosin and actin. On SDS-PAGE of myosin B treated with B.T.G., the monomeric myosin heavy chain decreased markedly with increasing amount of B.T.G. and a polymer fraction increased. Analysis of actin by SDS-PAGE indicated that actin was also polymerized. The small amount of B.T.G. increased the turbidity of myosin B induced by heating of linearly increasing rate of 2°C/min, suggesting that myosin B suspension with B.T.G. formed a finer network structure of heat-induced gel than that of myosin B alone. When the myosin B solution with B.T.G. was heated and then the heat induced gel centrifuged; tropomyosin and troponin-T were not freed from the sediment. These results suggest that the regulatory proteins play some role in the heat-induced gelation of this system.

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In the early stage of the boiling process, the water content, the weighing percentage and the degree of gelatinization of noodles increased rapidly. Large vacuoles were observed in the core of the noodle. The microstructure in the exterio rpart became dense. In the midle stage, fine vacuoles were formed in the exterior part of the noodle. The structure of this part became fine spongy when the noodle was thoroughly boiled. The diameter in vacuoles became large when noodle was boiled too long. The microstructure in the core part of noodles changed somewhat slower than in exterior part. The structures of these two parts were different from each other when the noodle was thoroughly boiled. The changes in elasticity of noodles corresponded to those in the microstructure during the boiling process.

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An attempt was made to examine the quality of sweetened adzuki ann prepared underpressured kneading at 100-120°C. The following improvements were obtained in the pressured kneading. (1) Since internal pressure of the cooker changed very little as from 0.15 to 0.25kg/cm² during kneading at a constant temperature, the ann granules were hardly damaged. (2) After pressured kneading process was finished, the sweetened adzuki ann was allowed to cool to 80°C on standing, and then cooled rapidly. This procedure gave little damage to it and liberated adzuki starch of under 2% from the ann granules. (3) After pressured kneading at 80-120°C, increasing the inner pressure of the oven to 0.25-0.50kg/cm² before rapid cooling kept the positive pressure in the oven, and prevented the ann granules from cracking. (4) By employing the pressured kneading, the volume of sweetend adzuki ann could be increased ten percent, and the kneading time was shortened, resulting in energy saving of 20-40%.

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An attempt was made to optimize the conditions for the manufacture of syrupped adzuki ann by using the automatic ann making pilot plant developed by the authors. The results were as follows: (1) To prevent the boiled adzuki beans from hardening, heating temperature should be set above 70, 80 and 90°C when the concentrations of sugar were 60, 70, and 80% (w/w), respectively. (2) The sugar solution should be concentrated very slowly at 75-80°C. Concentration of the sugar solution from 40% to 45% (w/w) over 3 hours prevented adzuki ann from hardening.

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The contents of potassium, sodium, calcium, magnesium, phosphorus, iron, copper, zinc, manganese, cadmium, lead, arsenic and mercury in 13 species (17 samples) of wild edible mushrooms and 4 species (6 samples) of cultivated mushrooms growing on woods wermushrooms and 4 species (6 samples) of cultivated mushrooms growing on woods werdistricts from 1979 to 1986.
The results were as follows; K: 02-6.8%, Na: 8-206mg/100g, Ca: 8-126mg/100g, Mg: 20-168mg/100g, P: 28-1370mg/100g, Fe: 1.1-68.6mg/100g, Cu: 0.1-4.0mg/100g, Zn: 0.2-8.1mg/100g, Mn: 0.4-3.9mg/100g, Cd: BDL (Below Detectable Level)- 4.64ppm, Pb: BDL-5.44ppm, As: BDL-0.27ppm and Hg: BDL-1.21ppm.Some characteristics were found in the mineral contents of the samples belonged to the same family, genus and species. Polyporaceae exhibited lower concentration of minerals than the others except iron. The mineral contents in Armillariella were generally high and in definite range except calcium and iron. The mineral contents in Armillariella mellea and Laeti-pororus sulphureus were in definite range except calcium. The mushrooms growingin soil exhibited significantly (p<0.01) greater concentrations of copper, zinc, manganese and mercury than thosegrowingonwoods. OnTricholomataceae, the mushrooms growingon woods exhibited significantly (p<0.05) greater concentration of magnesium and less con- centration of mercury than those growing in soil.

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[in Japanese]

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To clarify desirable features of shredded cabbage, the relation between desirability according to a consumer panel and physical and chemical properties of the cabbage was investigated using 5 carefully selected cultivars. (1) The physical and chemical properties of the shredded samples having high desirability with respect to appearance, color, juiciness, firmness and taste are summarized as follows: small midrib size and thin mesophyll for appearance; high chlorophyll content and pale or light greenish yellow of inner leaves fox color; high rate of dripping fluid from finely shredded samples under a fixed loading condition for juiciness; low puncture resistance of mesophyll for firmness; and low allyl isothiocyanate for taste. (2) Considerable juiciness, softness and good taste were the most important quality features for a high overall evaluation of shredded cabbage. properties of material cabbage.

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