The thermal behavior of kuzu and sweet potato starches was investigated by differential scanning calorimetry (DSC). In the present experiment, samples were defatted with 85% methanol solution. Heating speed of DSC was programed at 5deg/min. Peak area (cal/g) and three temperatures, i.e. onset, peak (T_p) and conclusion temperatures were measured. T_p of kuzu starch was lower than that of sweet potato starch and distributed in the range of 60 to 69.3°C. The starch produced in Korea was the lowest and that produced in Nara was the highest in them. In sweet potato starch, T_p was in the range of 72.5 to 74.3°C and no difference of the place of production was observed. Amylose content of kuzu and sweet potato starches was measured by the iodo-starch reaction. Defatted samples were gelatinized with 1 N sodium hydroxide solution, reacted with iodine, and then the absorbance of the complex was measured at 680nm. Amylose and amylopectin prepared from kuzu starch were used as standard. The amylose content of kuzu and sweet potato starches was in the range of 19.0 to 22.6% and 21.5 to 22.0%, respectively.

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A method for determining isofavone derivatives such as puerarin, daidzin and daidzein in kuzu starch by thin layer chromatography-densitometry has been developed. These compounds were extracted with methanol from kuzu starch by refluxing on a water bath. The extract was spotted on a silica gel plate, and developed with the lower layer of chloroform-methanol-water (65:35:10). These componds on the developed plate was determined by densitometry on zig-zag scanning mode with ultraviolet detection. Nine kuzu starch were measured. As a result, daidzein was detected in all samples in the range from 24 to 270ppm, puerarin was detected in four samples less than 53 ppm, and daidzin was not detected in any sample.

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The popping mechanism of popcorn grain (Zea mays everta), when heated at 200°C or at 220°C under atomospheric conditions, was studied in terms of; i) comparison of starch granule isolated from several kinds of corn grains, ii) characteristics of the structure of grains and iii) scanning electron microscopic observation of popping grains during heating. (1) Property of the starch granule isolated from popcorn did not differ from that of dent corn so much in gelatinization temperature and pasting characteristics, although its amylose content was slightly higher than that of dent corn (by 3% or so). The differences in the structure of grains were rather prominent to characterize the popcorn. (2) From the scanning electron microscopic observation of popcorn grain during popping, the starch in hard endosperm was gelatinized higher than 160°C and make a honeycomb structure by the expansion of vaporized air. In the popped products thin film-like membrane was made by the ge1atinized, sintered starch. (3) It was found that the starch granule gelatinized at the range of 130-170°C in the popping corn grains and the degree of gelatinization was about65-75%, The nature of hull, being able to tolerate the inner vapor pressure enough during heating was essentially important for the preparation of popcorn.

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To breed a high vitamin B_l2 producible natto strain, protoplast fusion was done betweenBacillus natto, Takahashi No.2 (Arg-mutant), and a vitamin B₁₂ productive strain, Bacillus megaterium IAM 1166 (Try-mutant). Lysozyme of 250μg/ml and 500μg/ml wasadopted for the protoplast preparation of B. natto Takahashi No.2 and B. megaterium IAM1166, respectively, with 10% sucrose at 42°C for 30min. Protoplast fusion was carried outwith 40% polyethyleneglycol 6000, and the regeneration was performed on SucroseGlutamateminimal medium containing 10% sucrose and 3% polyvinylpyrolidon. Preservation of thestringiness and vitamin B₁₂ productivity of the protoplast strains were deeply affected by theconcentrations of lysozyme and sucrose. Three fusants which were capable of producingstringiness and vitamin B₁₂ were isolated on SG medium, and the strong stringiness on asteamed soybean by them were also observed in a similar manner as B. natto.

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Oyster mushroom (Japanese name: hiratake) was cultivated in Cu, Cd, Pb and Ge fo rtified culture media, which consisted of 4 parts of shell of groundnuts and l part s of rice bran(moisture was adjusted to 60%). Fortification levels were 0-100μg/g of Cu, Cd and Ge and 0-30μg/g of Pb on air dry basis. Growth of mushroom and absorption of Zn, K, P, Mg, Mn, Fe and Ca by mushronm was not affected by fortification of Cu, Cd, Pb and Ge. Neither Pb nor Ge were absorbed by mushroom. Absorption rate of Cu lowered in fo rtified culture media, compared with that in unfortified culture media. Concentration of Cd in mushroom straightly increased according to that of Cd in fortified culture media . Concentrations of these elements in pileus were higher than those in stems. Ratio of e lement concentration in pileus to that in stem ranged from 1.1 in Fe to 2.1 in Cd. Charact eristics of distribution of each element was suggested. The concentration factor to pileus o f mushroom from culture media were 2.7 in Zn, 1.08 in Cu, 0.97 in K, 0.95 in P, 0.38-0.79 in Cd (fortified culture media), 0.21 in Mg, 0.10 in Mn, 0.05 in Fe and O.008 in Ca. AI was not absorbed.

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Cooked soybean paste containing 10% lactic culture (Streptococcus thermophilus: Streptococcus lactis=1:1) was prepared. After adding 2% sodium chloride and inoculating P.caseicolum as a mold starter, the paste was ripened for 3 weeks under a definite condition.Cooking of soybean at 120°C for 30min was more suitable fo making fermented soybeanpaste than at 100°C for 2h because of lower browning o soybean, higher acidity and proteindegradation of paste during ripening. On ripening at 15 and 23°C, the mild flavor productwas obtained on ripening at lower temperature. By addition of lactic acid bacteria to thepaste, acidity in the paste was increased at 1 week, but the acidity rapidly decreased withprogress of ripening and pH value in a ripening product raised to 8.0 at 3 weeks. The ratioof water soluble nitrogen to total nitrogen (Protein solubility ratio) reached to approximate60% in the product at 3 weeks. Total free amino acid amount was 869mg/100g and thehighest concentration of liberated amino acid was glutamic acid (187mg/100g). Linoleicacid was the highest amount of liberated fatty acid in the product at 3 weeks (484mg/100g).

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Spaghetti samples were prepared from defatted durum semolinas with different protein content (about 19%, 14% and 10%) with or without oleic acid. Effect of oleic acid on the cooked spaghetti properties was investigated in connection with protein content of the sample by measuring tenderness index, compressibility and recovery, stickiness, hardness and cohesiveness, tensile strength, Young's modulus and maximum elongation. Results indicated that changes in physical properties of cooked spaghetti caused by the presence of oleic acid such as increase in hardness, Young's modulus and tensile strength or decrease in compressibility and stickiness were mainly attributed to the effect of oleic acid on starch for the samples containing protein up to 14%. However, a marked decrease in maximum elongation by oleic acid was observed for the samples of 14% and 19% protein, which appeared to be due to the effect on gluten. The increase in hardness of cooked spaghetti might be also related to the change in gluten caused by oleic acid.

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Cooked rice was freeze dried in a vibrated bed freeze dryer. Weight ratios of water added to raw rice before cooking were 1.4, 1.5, and 1.7 for polished rice, and 2.0 for brown rice. Cooked rice was treated with potato starch before freezing to diminish sti ckiness of the product. Particles of frozen rice were mixed well in the drying chamber by vibration. Bed temperature could be kept low and nearly uniform during the most part of the drying processes. The drying rates were nearly 3kg-H₂O/(m²·h). Packing densities of the freeze dried products ranged from 435 to 465kg/m³, and the values decreased with increasing the molsture content of the cooked rice. About 5minutes rehydration of the dried products in boiling water made the moisture content the same value of the cooked rice. The rehydrated rice had almost the same appearance as the cooked rice. The texture profile analysis for each particle of the rehydrated dried rice products was applied to discuss the quality of the products. Total work and gumminess (cohesiveness×hardness) of properly rehydrated products were very close to the values of the cooked rice. The value of adhesiveness/hardness was also useful index for quality evaluation.

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Effect of treatment with some kinds of sugar esters (0.35% C-12:0, 14:0, 16:0, 18:0 and 18:1) on the fruit colour and occurrence of chilling injury of kabosu fruit (Citrus sphaerocanrpa hort ex TANAKA) durings torage at 1°C was investigated. Decrease of fruit weight, degreening of fruit colour and rate of occurrence of chilling injury during storage were inhibited by the treatment with sugar esters. There was no distinct difference among the external quality of fruit treated with different kinds of sugar esters. However, treatment with sugar ester-miristerate (14:0) and palmitate (16:0) tended to show better green colour on the fruit surface than those treated with other sugar esters.

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An exact and rapid calculation system by the use of a personal computer (PC) was applied to the phase difference method for dynamic rheometer with a longitudinal vibration of lower frequency ranges (1-100Hz). Two kinds of methods were investigated to transmit the stress and strain signals generated by the rheometer to the PC. One is composed of a PC equipped with a digital storage oscilloscope through a GP-IB interface. In the other system, the signals are directly transmitted to the PC through an analog to digital (AD) converter. The former has faster AD conversion time (1μsec.), and it brings the finer sinusoidal stressstrain curves at the frequency over 30Hz. Whereas, the latter has advantages in a short measuring time and in a cost of the apparatus. The results by this sys tem included both the transmission method were compared with that by the manual calculating method for 3% agar gel, commercial process cheese, and silicon oil (10⁴cs). The stress and strain amplitudes on the system can be established with the coefficient of variation below O.1%. The program developed in this work permits easily alteration of various experimental conditions by input of the initial values, and it is possible to be applied not only for solid food specimens, but also for any other liquid states.

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A rotary-type cultivation box was developed for use in cultivation of thick bea sprouts Using this box, an attempt was made to produce thick bean sprouts from soybean a nd mung bean by intermittently applying short time rotation, and growth and quality of t he bean sprouts were studied. An octagon type box was deviced and then was rotated at tw o different speeds (low speed: 5rpm, high speed: 10rpm). Material beans were germi nated for two days in a usual way and, immediately thereafter, put in the rotary-type box and treated with rotation at 5 or 10rpm for 10min every 8h every day. Cultivation in the rotary-type box had a remarkable effect on the growth and quality of the thick b ean sprouts. The cultivation in octagon type box rotating at low speed made it possible to pr oduce commercially favorable, high-quality"thick" sprouts, because it was extremely effective in increasing length and thickness of the hypocotyls. The high speed rotation of th e box was judged to be inappropriate, since it gave an excessive growth inhibition resulti ng in commerially unfavorable products. Root growth was significantly inhibited by cul tivation in the rotary-type cultivation box, where a considerable inhibition of elongatio n and increase in number of hypocotyls developed took place. The suitable time for harvest as j udged in terms of market acceptance was reached after 5 days' rotation-treatment, which m eans reduction by 2-3 days of the cultivation time. It was also confirmed by a stati stic By using it, cultivation and production of commercially favorable thick bean sprouts that mee t consumer requirements was made possible.

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Birds used in this study were commercial strain of White Leghorn hens, which reared to 528 dags old on commercial formula feed for chicken. Edible portions of hens (breast and thigh meats, liver, heart and gizzard) were estimated about one third of their l iveweight. Liver had the highest level of lipid, and breast meat had the least among tissues teshed. The major fatty acids in lipids from hens were palmitic, stearic, oleic and linoleic acids. Levels of polyunsaturated fatty acids were comparatively high in tohal lipids from hens. Though the polyunsaturated fatty acids were a little, the neutral lipid fractions from hens had high levels of oleic and linoleic acids in every tissues. The most pronounced differences between neutral and phospholipid fractions were in the high levels of stearic and arachidonicacids, low level of oleic acid, and large amount of polyunsaturated fatty acids in the phospholipid fraction as compared to the neutral lipid fraction. The results indicate the approximate susceptibility of laying hen tissues to oxidative rancidity.

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