Preparation of protein rich flour from rice was investigated by air classification and electrostatic separation. Electron microprobe X ray analyzer revealed that rice protein was distributed-mainly in about 25% region of endosperm from its outerlayer. After being polished from 91% to 75%, rice flour was found to have the protein content upto 14%, compared with 7% of rice grain polished to 91% of initial weight. Moreover, this protein rich flour was raised up its protein content at maximum to 17.5% after air classification and its main particle size was estimated around 40μ by scanning electron microscopy. Electrostatic separation can be useful to the rice coarse flour (over 100μ) dispersable in the air but not suitable for rice fine flour (below 100μ) because of their tight aggregation. Protein rich coarse flour was always attracted to the positive electrode under the low potential around 2.5kV, which indicates that protein rich coarse flour has negative charges on the surface. However, rice flour was distributed uniformly between electrodes regardhess of the protein content when high voltage was applied over 7kV. It is noticeable that even fine flour below 30μ was increased its protein content by 2% after repeated electrostatic separation. This separation would be promising if its efficiency was improved.

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A modified enzymatic method for assaying cyanide content of butter beans (Phaseolus lunatus L.) imported from Burma for "Ann" manufacture was descrived. To liberate HCN from its glycosides, the enzyme was extracted from powder of the beans with M/10 citrate buffer (pH 6.0). The cyanogenic glycosides in dry beans, as well as soaked ones, were extracted with 80% ethanol under reflux, and treated with the enzyme to liberate HCN which was estimated spectrometrically after distillation. The inherent free HCN was estimated after distillation with acids without the enzymatic treatment. Results obtained were as follows: 1) The optimum conditions for the enzymatic assay were 50°C, pH 5.5. 2) When the mixture of enzyme and extract containing cyanogenic glycosides from beans was incubated at 50°C for 1.5hr, 89.1% of the glycosides was recovered. 3) Fifty percent or more of the cyanogenic glycosides was remained intact in beans during soaking in water at 20°C for 18hr or 50°C for 4hr. 4) Commercial enzymes containing various types of glycosidase had no liability for liberation of HCN from cyanogenic glycosides. A little HCN was liberated from the glycosides by treating with mineral acids at 40°C. HCN equivalent to about 50% of the glycosides was liberated by boiling with 1N HCl for 1hr.

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A study was carried out to establish a new manufacturing process of "Ann" from beans containing cyanogenic glycosides without soaking process which is obligated by "Japasese Sanitation Law". The contents of cyanides in beans and waste water at various stage of processing were determined. 1) When beans were boiled with water several times without soaking process, little HCN was liberated and intact cyanogenic glycosides existed both in waste water and boiled beans. 2) To inactivate the enzyme which liberate HCN from cyanogenic glycosides in beans, heating at 100°C for 20min was confirmed to be satisfactory. 3) Little HCN was liberated in any stage of processing without soaking process in a laboratory, and after the boiling was repeated four times the boiled beans contained free HCN corresponding to only 0.01% of the cyanogenic glycosides in dry beans, while the final product "Ann" contained intact cyanogenic glycosides equivalent to 1.5% of that in the raw beans. 4) In a factory, by use of the new method, the final product "Ann" containing 0.02mg/kg of free HCN and 0.01mg/kg of cyanogenic glycosides as HCN was more effectively produced than using the conventionl method.

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Phase transitions of monoglycerides (MG)-water and MG-water-soybean oil (SBO) mixtures have been observed by using seven kinds of MGs, and their phase diagrams were prepared. MG-water mixture with the lower water content (lower than about 55%) transfered to neat phase (N), viscous isotropic (VI), and fluid isotropic (FI) successively by heating, while the mixture with higher water content changed to dispersion (Dn), (VI+water) and (FI+water) sequentially by heating. Neither transition from VI to N nor that from (VI+water) to Dn were observed. Temperature ranges of the phases depend on the fatty acid composition of the glycerides. The larger the molecular weight of MG is, the higher transition temperatures of all phases were observed. The transition temperatures of unsaturated fatty acid MGs were lower than those of saturated fatty acid MGs. Crystalysation temperature was lowered and ranges of four middle phases (N, Dn, VI and VI+water: liquid crystals) were reduced by adding SBO to the MG-water mixtures. NaCl reduced the range of N and Dn of both MG-water and MG-water-SBO samples. The both phases were extinguished by adding larger amounts of NaCl, and the ranges of VI and (VI+water) were enlarged consquently.

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Recently, consumer's demand for beans sprouts having 'heavier hypocotyl' (short and thick) is increasing. Present study was carried out to investigate the applicability of artificial lights to produce e fficiently the heavier hypocotyl sptouts, using soybeans, mung beans, and adzuki beans. The beans sprouts were cultivated in the dark chambers at 30°C, and the artificial lights (artificial sunlight lamp, infrared ray lamp, and ultraviolet ray lamp) were applied for 60 minutes every day from 3 days after initiation of cultivation at 500lux, respectively. With three kinds of beans sprouts tested, the application of artificial sunlight showed a marked acceleration of the increases of length, diameter, weight, and hardness of hypocotyls in 1-2 days, and vitamin C content was considerably higher than the sprouts cultivated with conventional method, thus produced heavier hypocotyl sprouts with good quality. Treatment with infrared ray lamp showed a similar tendency, but the effect was inferior to artificial sunlight lamp. From 3 to 5 days after initiation of the application of artificial lights, the hypocotyls of sprouts became too long and thin, and many lateral roots appeared. Application of ultraviolet ray lamp resulted in an inhibition of hypocotyl elongation in 1-2 days. Surface color of the hypocotyls tended to became yellowish by the artificial lights, especially by sunlight lamp, but kept acceptability whithin 2 days.
It is concluded that the short time application of artificial sunlight and infrared ray lamps could shorten the duration of cultivation by 1-2 days to produce the beans sprouts with heavier hypocotyls.

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The rheological difference between the agar-agar gels prepared from Makusa (Gelidium amansii) gathered in spring and summer was examined on the basis of vibrational, stress relaxational, and ultrasonic measure- ment. Relaxation curves up to 10hrs for the gels containing 1-5wt% of agaragar were obtained in the temperature range from 25°C to 73°C. The melting temperature of the gels and the intrinsic viscosity of the aqueous solutions were also determined. The summer seaweeds contain larger amounts of sulfate residues than the spring seaweeds. Judging from the values of the intrinsic viscosity, the molecular weight of the agar-agar extracted from summer seaweeds was larger than that from spring seaweeds, The gels prepared from the summer seaweeds show greater values of relaxational modulus, storage modulus and melting temperature than the gels prepared from the spring seaweeds. In the concentrated gels the relaxation spectrum shows a greater value in summer seaweeds than in spring seaweeds at the longer time scale. In the lower concentration, there was not so much greater difference for the relaxation spectrum between the summer seaweeds and spring seaweeds. Therefore, it was suggested that at higher concentration, the molecular weight plays a dominant role in the gel formation, and at lower concentration, the sulfate residue content is also an important factor in the gel formation.

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In order to elucidate the cooking characteristics of gelatinized rice, experiments measuring its physical properties and sensory evaluations were conducted using both non-glutinous and glutinous rice. The non-glutinous rice was gelatinized up to 79.2% and the glutinous rice to 95.8%. Amylography of rice powder showed: Gelatinized non-glutionous rice increased its viscosity slowly from about 65°C and no 'breakdown' was observed. However, the highly gelatinized glutinous rice reached the maximum viscosity immediately after the measurement was started. This is considered a very unique amylogram. The textural properties of cooked rice were as follows: Both glutinous and non-glutinous rice in a gelatinized state were harder and more cohesive than polished rice. Glutinous rice was stickier than non-glutinous rice, however, both gelatinized types were less sticky than polished rice. The 'creep curve' of the cooked rice was obtained with a creepmeter to analyze the static viscoelasticity. Every sample could be explained according to the six element models of Hookean body, two pairs of Voigt body, and Newtonean body. The elastic modulus were 10⁵ to 10⁶ dyn/cmcm², and the coefficients of viscosity were 10⁷ to 10¹⁰ poise. The hedonic scale values in sensory evaluation of cooked rice were closely related to their physical properties. However, the appearance of gelatinized rice was slightly inferior to polished rice.

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Relationships between heat denaturation of soy protein and its functional properties were investigated in order to examine the effects of the heat treatment employed in the isolated soy protein (ISP) production. The formation of aggregate determined by Sepharose 4B gel filtration was favored by the heat treatment of the acid precipitated protein (APP) solution in the temperature range 70-95°C at pH 7. An increase in protein concentration also promoted the thermal aggregation. The flow behaviour of the heat-treated APP solution was characterized by the structural viscosity, and the promotion in the aggregate formation was accompanied with the higher apparent viscosity and the lower n-value according to the power law. This flow characteristics strongly indicated the presence of protein-protein interactions leading to the formation of protein network. The water-holding and heat-induced gel forming properties of the rehydrated paste of the ISP prepared by spray-drying the heat-treated APP were closely related to the degree of aggregate formation. The data obtained here suggest that protein-protein interactions during thermal aggregation serve as a mechanism for the network formation and that these two functional properties of the ISP are governed by the extent of the network formation controlled by the heat treatment conditions of the APP.

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To keep krills in good quality is one of the important problem in utilizing them for food or food products. The effect of precooking before freezing on the cooked odor of krills were investigated. Both precooked frozen and raw frozen krills were used as materials. The cooked odor concentrates were obtained by a simultaneous distillation and extraction system. Two fractions which showed the characteristic patterns on the preparative gas chromatogram were trapped and the individual fractions were analyzed by combining gas chromatography and mass spectrometry. The compositions of the two fractions were compared between precooked sample and its control (i.e. raw sample). A large quantity of pyrazines was found in the control sample, while precooked sample contained a large quantity of the sulfur containing compounds such as thialdines and trithiolanes with a small amount of the pyrazines. It was presumed that the difference of odor compositions between the precooked sample and its control was caused by the different mechanisms of their formation which influenced by the quantities of ammonia and free amino acids.

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Some differences in antioxidative activity were observed among sesame oils prepared by different purification processes. The HPLC analysis on methanol extracts indicated that 30μg/g oil of sesamol was detected only in the roasted sesame oils, while 190 μg/g oil of γ-tocopherol was detected in the crude sesame oils. Only trace amounts of γ-tocopherol and sesamol were detected in the pressed cake, however, strong antioxidative activity was observed in it. These results seem to suggest the presence of other antioxidative factors in sesame seed and pressed cake.

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