Textural properties of salted radish root were evaluated by organoleptic test as well as measurement with a Texturometer to investigate the mechanism of the increase of the hardness during salting. The result obtained were follows: (1) The hardness of the salted radish root differd depending on the portions. Linear relationship was found between crispness or "Hagire" by organoleptic test and hardness by a Texturometer. (2) The hardness was found to increase gradually along with increase of Ca- and Mg-contents during salting. (3) Soluble pectin in 0.4%-hexametaphosphate solution increased in the early stage of salting period, while methoxyl group contents in pectic substance decreased gradually though salting period. As a result, it was presumed that the increase of hardness of radish root during salting was caused by; 1) the increase of viscosity of radish root pectin depending on the decrease of methoxyl group contents, 2) the change of physical properties of pectic substance resulted from the increse of calcium and magnesium content and 3) the change of tissue of radish root due to dehydration by sodium chloride.

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Free sugars, free sugaralcohols and organic acids in the ethanolic extracts of over-thirty species of edible mushrooms were investigated by gas-liquid chromatography. The results were obtained as follows: The amounts of total free sugars and total free sugaralcohols obtained from these edible mushrooms were found in the range of 0-22.3% and 0.1-19.2% in dry materials respectively. In these edible mushrooms, trehalose, mannitol, arabitol, glucose and glycerol were identified. Trehalose and mannitol were found to be predominant in samples, and glycerol was also found in all the samples. The distribution patterns and contents of free sugars and free sugaralcohols were low similarities among different species of edible mushroom. Organic acid contents were found in the of 0.3-5.8% in dry materials and ten kinds of organic acids (malic, fumaric, succinic, citric, pyroglutamic, α-keto-glutaric, oxalic, lactic, acetic and formic acids) were indentified. Malic, fumaric, succinic, pyroglutamic and citric acids were found to be predominant in samples, and oxalic acid was also found in all the samples. There were remarkable differences in the distribution patterns of organic acid compositions among the different species of edible mushroom.

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The effect of electrolytic reduction on viscosity and gel formation of an acid precipitated soybean protein solution was investigated. The electrolytic reduction current was set at 10mA (current density, 2.5mA/cmcm²). Acid precipitated protein was prepared from U.S. soybeans (1979 crops, Ohio) stored under the conditions of 40°C and R.H. 75% for 30 days. The amount of sulfhydryl group and pH value of the soybean protein solution increased with the application time of electrolytic reduction. The relative viscosity of the solution researched to a maximum value after 120 min-electrolytic reduction. On further application, the viscosity decreased gradually. The increase of viscosity of the solution by heating was remarkable in the absence of electrolytic reduction treatment. GDL (glucono-delta-lactone)-gel prepared from the acid precipitated protein solution treated with the electrolytic reduction was harder than that obtained from the solution without the application of the treatment. The hardness of GDL-gel as well as the viscosity of the solution showed a maximum at 120 minutes after the start of electrolytic reduction. It was suggested that the decrease of hardness of GDL-gel prepared from the protein solution heated excessively was farily restrained by applying the electrolytic reduction to the solution.

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The effect of electrolytic reduction on the dielectric properties of the acid precipitated protein solution prepared from "old soybean" stored at 40°C (R.H. 75%) for 30 days was investigated. The electrolytic reduction current was set at 10mA (current density, 2.5mA/cmcm²). 1) The dielectric constant and dielectric increment of the solution had maximum values at 120 minutes after the start of electrolytic reduction. On further application, they decreased gradually. 2) The dielectric constant showed high frequency dependence and the anomalous dispersion was found in the frequency range from 1 to 10MHz/sec. 3) The dispersion of the dielectric loss had a wel-defined shape with a single peak between 1 and 3MHz/sec. With the application time of electrolytic reduction, the peak once shifted towared lower frequencies, and then higher ones. 4) In the frequency range from 10 to 100MHz/sec, the specific conductance appeared to depend on frequency and the frequency dependence increased with the application time of electrolytic reduction. 5) A plot of dielectric constant against dielectric loss at each frequency showed semi-circle in agreement with the equation of Cole and Cole. The dipolemoment μ, and mean dielectric relaxation time τ₀ and its distribution parameter α had maximum values at 120min-electrolytic reduction. On further application, they decreased gradually.

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Guava contained fructose, glucose, surcrose, and inositol in the decreasing order. Reducing sugars mainly composed of fructose and glucose increased slowly during the period of immature and mature stages, and increased sharply at ripening upto full ripe stage. Although the concentrations of both fructose and glucose were higher in white, C-1-16 seedling variety than in pink, C-1-40 seedling variety in either of the immature and mature stage, only with the exception of fructose at maturation where it was higher in pink. At full ripe the pink variety contained more fructose and glucose than the white and at ripening the concentrations of froctose and glucose were almost nearing to equal to each other but at full ripe fructose comprised 55.93% of total sugars in the white variety and 58.28% in the pink. Sucrose and inositol constituted the minor sugar components and also increased gradually with insignificant rise of concentration during ripening. Activity of invertase began to develop during ripening and attained the maximum at full ripe. This enzyme showed a maximum activity at pH 3.5-4.0. Amylase activity started to increase as the fruits reached the maturation and increased upto full ripe and showed the optimum pH 7.0. Although, at ripening the white variety had higher invertase activity than the pink, amylase activity of the pink variety was 2.1 times higher than the activity of the white.

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Carotenoid pigments in fruit flesh of ripe tomatoes of the typical strains (Red, Yellow, Tangerine, Apricot, Beta orange and Delta strain) were studied by means of column chromatography and thin layer chromatography. The spectral absorption curve of each carotenoid was measured by a spectrophotometer. Further, the carotenoid content was calculated by using the absorption coefficient of each carotenoid. The results obtained were as follows (unit: μg/g): 1) The Red strain contained lycopene (53.9-66.5), β-carotene (4.5-4.9), and γ-carotene (0.5-0.9). 2) The Yellow strain contained β-carotene (1.1-1.7) and almost no lycopene. 3) The Tangerine strain contained δ-carotene (29.8-36.0), prolycopene (27.5-36.1), proneurosporene (6.6-10.6), β-carotene (2.0-5.0), lycopene (1.6-3.2), neurosporene (1.1-2.9) and γ-carotene (trace). 4) Apricot strain contained β-carotene (3.1-6.5), γ-carotene (trace) and almost no lycopene. 5) The Beta orange strain contained β-carotene (54.5-69.3), lycopene (2.4-4.4) and γ-carotene (1.8-3.6). 6) The Delta strain contained δ-carotene (21.1-31.1), lycopene (19.4-27.6), β-carotene (2.8-6.0), α-carotene (0.8-1.4) and γ-carotene (0.7-0.9). The Red, Tangerine, Beta orange and Delta strains contained phytoene (3.0-6.5) and phytofluene (14.3-25.4), while all strains contained a small quantity of xanthophylls (2.7-6.0).

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Chemical properties of total lipids and neutral lipids in flesh and skin of immature (picked on June) and mature (picked on November) fruits of persimmon, Disopyros kaki L. (3 varieties of Fuyu, Zenjimaru and Koshuhyakume) were studied by means of column, thin-layer and gas-liquid chromatography. The total lipid contents in the above two parts of immature and mature fruits were 0.08-0.23%, and the neutral lipid contents in the total lipids were 73.5-88.6%. Fatty acid compositions of the total lipids were studied by gas-liquid chromatography, and 13-16 kinds of fatty acids were identified. Main fatty acids in the total lipids were linolenic (20.2-31.1%), oleic (20.4-28.2%), palmitic (16.8-23.6%) and palmitoleic acids (12.1-18.3%). Main components of the neutral lipids in flesh of immature and mature fruits were triacylglycerines (23.2-33.3%), 1, 2-diacylglycerines (13.8-24.2%) and sterols (12.0-20, 9%). On the other hand, sterols (9.5-12.1%) were detected as main components of the neutral lipids in skin of immature and mature fruits, but many unknown components were also observed.

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Mass transfer in fish flesh has been reported in our previous papers, especially in extraction of fish oils and water-soluble-proteins. In this study transfer rates were measured in extraction of salts at several conditions and in penetration of NaCl. In both operations, under the every conditions employed transfer rates were represented by FICK's law of diffusion, and the mass transfer rates perpendicular to the direction of fiber were in accordance with those parallel to that. The effect of temperature on diffusivity in fish flesh was same as that in water. But the rates of diffusion in denatured flesh by cooking were lowered in comparison with those in raw flesh. Correlation of the diffusivities of several kind of salts in fish flesh were different from those in water depending upon the valencies of the cations. And these phenomena were also observed in the case of simultaneous diffusion of uni and bi-valent cations.

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A soybean acid precipitated protein (APP) was stored at relative humidities of 11%, 47% and 96% at 50°C in order to investigate the effect of humidity on the changes of APP. The solubility of APP stored at RH 96% drastically decreased in a few days, on the other hand, when stored at RH 11%, the solubility did not decrease in 45 days. Gel filtration study revealed that soybean protein polymerized during storage and became insoluble. When stored at RH 11% for 45 days, there was no change in the quarternary structure of soybean protein. It was suggested that hydrogen, hydrophobic and disulfide bond were related to the insolubiliaation during storage.

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The influences of moisture content, storage temperature and carbon dioxide on the quality change in the packaged buck wheat were determined by the germination test and the measurement of fat acidity and reducing sugar content. (1) Better quality retention of the packaged buck wheat was obtained under the condition of lower moisture content and lower storage temperature. The moisture content was defined to be lower than 13.8% in oder to keep the good quality for 10 months at 30°C. (2) Under the storage condition at 30°C, carbon dioxide did not show the protective effect for the quality change in the packaged buck wheat. (3) The major factor affecting the increase of fat acidity of buck wheat was related to the free fatty acid content. (4) The analysis of buck wheat after one year of storage at 30°C showed that the relative amount of linoleic acid in total fatty acid was higher than those in the free fatty acids, while C²⁰<-fatty acid was lower.

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