Volatile componenets in hydrolysates of horseradish and black mustard flour were investigated by gas chromatography. 3-Methylthiopropyl(3-MTP-NCS)and β-phenylethyl isothiocyanate (β-PE-NCS)were detected as critical components between both materials. The peak area of 3-MTP-NCS in black mustard was more than that in horseradish, whereas horseradish contained a large amount of β-PE-NCS more than that in black mustard. The mixing ratis of black-mnstard and hoseradish powder in "Wasabi powder" can be calculated from the X value(the ratio of the peak area of 3-MTP-NCS to that of β-PE-NCS).

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Mechanical properties of radish and their changes caused by freeze-thawing were measured by the method in the previous report. Little deviations of the texture to the directions of both cross section and longitude in the same individual of fresh radish were observed except narrow cambium and phloem zones in the surface layer. Blanching in boiling water was more suitable for the texture of radish than by steaming. Blanching time increased in proportion to the volume of the specimen, not to the shape. The increase of blanching time brought forth a marked softening to the large specimen which is eaten as cooked food in Japan. Air blast freezing and thawing in boiling water of the specimen reduced its firmness by about 50%, but this decrease is small as compared to the decrease in the case of carrot. It appears that the texture of radish is endurable to the treatment of freeze-thawing, but not resistant to heating. Dielectric thawing with a 2450MHz microwave oven was found to be not so much effective as expected for the improvement of the texture of the frozen radish specimen compared to thawing in boiling water. The former is not always an effective method for frozen vegetables because of difficulties of temperature control of the specimen.

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Processed foods using vegetable proteins, the formulations of which were almost known, were investigated to identify vegetable proteins with disc acrylamide gel electrophoresis in the urea system. As for this experiment concerned, it was possible to detect the blending of more than 0.5% soybean protein and more than 1% wheat protein on the electrophoretical patterns of processed foods; however, linear relationship between the protein amounts added and the areas of the main peaks on the electrophoretical patterns could not always be obtained, and marked difference was found in the degree of staining depending on the kind of proteins used. Meats and eggs had subpeaks which located near the mainpeaks of soybean and wheat proteins so that they disturbed the identification. Heat processed foods such as retorted products provided obscure electrophoretical patterns in which the separation of each peak was not clear and the degree of staining decreased. Those facts let us consider the difficulty of identification of vegetable proteins in processed foods, such as so-called fabricated foods, especially quantitatively.

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Mature-green banana fruit stored at 40°C failed to ripen. Both of protein nitrogen(10% TCA-insoluble nitrogen)and total RNA content of banana fruit did not change during storage at both 20°C and 40°C. However, ¹⁴C-valine incorporation into protein in pulp tissue of banana fruit was completely inhibited at 40°C. The ability of protein synthesis in the tissue was rocovered from the inhibition after a certain lag period by transferring from 40°C to 35°C. The length of this lag period was dependent on the length of 40°C treatment and the subsequent incubation temperature. Incorporation of ¹⁴C-uridine into RNA was suppressed slightly larger at 40°C than at 35°C, but continuous incorporation was observed at both temperatures. Actinmycin D, an inhibitor of RNA synthesis, did not prevent the recovery of protein synthesis from the inhibition at 40°C. These results indicate that banana fruit held at 40°C failed to ripen by the decrease of protein synthesis caused by high temperature.

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In this study we discussed histological changes in an germinating rice seed by a light microscope, and obtained the results as follows. 1. During the germination of the rice seed, starchy tissue in the endosperm was degraded from the endosperm part adjacent to the epithelium of scutellum to the top part of the rice seed. 2. Starch granules in a starchy cell in the endosperm tissue were eroded from the part adjacent to the starchy cell wall, while starch granules of the central part in the starchy cell remained intact. 3. In the aleurone cell of an ungerminated rice seed, AS-positive material(protein)and aleurone granules were observed. But at the later stage of germination, they disappeared. 4. In the scutellum of the ungerminated rice seed, there was no starch granule, but when the leaf grow up to 3-4cm height during the germination, starch granules were accumulated in the cell of the scutellum and disappeared in the later stage of the germination. These phenomena suggested the existence of starch-granule-synthesizing and starch-granule-degrading enzymes in the cell of the scutellum. 5. In the epithelium of the scutellum of the ungerminated rice seed, AS-positive material(protein)was observed, but it disappeared at the later stage of the germination. Throughout the germination stage, few starch granules were observed in this part. From these results, we deduced that the starch-degrading enzymes in the endosperm tissue would be secreted from the epithelium of the scutellum and/or activated by secreted substances from the epithelium of the scutellum.

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The phenolics of Koshu white wine were fractionated into seven groups by column chromatography using Sephadex G-10 eluted with 3% acetic acid and distilled water. The fractions 1-5 contained non-phenolics such as protein-tannin complexes, fructose, glucose, guanine and xanthine. The fractions 6 and 7 contained tyrosol and three cinnamate derivatives, respectively. As flavanoles in wine not eluted from this column, these were determined separately by the precipitation method with folmaldehyde. The composition of phenolic compounds in new and old Koshu white wine was determined as follows. In new wine containing 400ppm of total phenolics, 140ppm of flavanoles(35% of total phenolics), 120ppm of cinnamate derivatives(30%), 36ppm of tyrosol(9%)and 79ppm of non phenolics(20%)were detected. In old wine, flavanoles were not detected but cinnamate detivatives, tyrosol and non-phenolics were still remained at some levels. The relation between total phenolics and flavnoles or cinnamate derivatives were ecual to(total phenolics-200)ppm×0.7 and(total phenolics)ppm×0.3, respectively.

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Two types of rice vinegar were produced through stationary and aerated processes.
(1) With respect to the general chemical components of the rice vinegar, no noticeable difference was found except for specific gravity. (2) The content of amino acids, especially glutamic and aspartic acids and alanine decreased during both the brewing processes. However, histidine in the stationary brewing and proline and arginine in the aerated brewing increased slightly. (3) In contrast, the amounts of non-volatile organic acids remained unchanged through both brewing processes. Gluconic acid was produced only in the aerated brewing process. (4) Ethanol in the aeration brewed vinegar remained longer than in the stationary brewed one. The gas chromatograms of both types of rice vinegar showed no noticeable difference. (5) In the sensory tests, the aeration brewed vinegar was superior to that produced by the stationary method.

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Emulsifying properties of a soybean protein(acid-precipitated protein)were measured with small quantities of the protein(about 10mg)by emulsification with a sonicator followed by tubidimetry with a photometer. Recommended conditions for measurment were as follows. Protein solution(1%, 1.4ml)and oil(0.6ml)were emulsified with the sonicator(20KHz)at 60 W for 3 minutes. The turbidity of this emulsion was measured at 500nm after the dilution to 2500 folds. This turbidity was closely related to the emulsion stability determined by measurement of water content in the low part of the emulsion after keeping it for 24 hours. The degree of flocculation was determined from the difference of turbidity between with and without a detergent(SDS)in a diluting solution for the emulsion.

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