Sensory evaluations were carried out to examine the effects of four seasoning additives, monosodium L-glutamate, DL-alanine, citric acid and lactic acid on the organoleptic qualitiy of film packed radish pickles employing the statistical orthogonal array L27(3¹³). Each radish pickle was added with 8% cane sugar and 5% salt as a base. 1. Radish pickles prepared by adding 0.05g citric acid and 0.4ml lactic acid to 200g salted radish showed more favorable odor than the other combinations of citric acid and lactic acid. 2. Radish pickles prepared by adding 0.2g or 0.4g monosodium L-glutamate showed more favorable flavor than those prepared by adding 0.8g monosodium L-glutamate-Radish pickles prepared by adding 0.1g citric acid and 0.4g lactic acid were more unfavorable than the other combinations of citric acid and laetic acid. 3. Radish pickles prepared by adding 0.4g monosodium L-glutamate and 0.1g DL-alanine showed suitable color than those prepared by adding 0.8g monosodium L-glutamate and 0.1g DL-alanine or 0.2g monosodium L-glutamate and 0.1g DL-alanine. Radish pickles prepared by adding 0.1g citric acid and 0.1ml lactic acid showed more un-favorable color than the other combinations of citric acid and lactic acid.

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The effect was examined on ultrafiltrability of caramel solution of the change in pH due to addition of sulfuric acid or sodium hydroxide. Ten % caramel solution of which pH was adjusted to the range from 1 to 13 was ultrafiltered to measure the flux and the rejection of coloring matters. The flux was almost constant over the pH range from 3 to 12, and progressively decreased below pH 3 and above pH 12. The rejection of coloring matters was varied little within the pH range from about 2.5 to 7, progressively increased below pH about 2.5, and progressively decreased above pH 7. These results showed that for releasing the bound imidazole compounds addition of an adequate of an adequate amount of sulfuric acid is desirable to avoid the excessive reduction of flux and rejection of coloring matters.

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A newly developed material for soy sauce manufacturing was obtained by extruding the mixture of defatted soybean flour (DSF), wheat flour and bran. Starch and protein in the material were thermally denatured under the condition where the moisture content of the starting material was from 30 to 40% and the particle size of DSF was 50 mesh through. Koji was prepared from the material by culturing for 45 hours, after sprinkling the predetermined amount of water and inoculation Koji-starter on a screw conveyor without cooking. Proteinase activity, one of the critical parameters for the quality of Koji, was the highest for the material with initial moisture content of 40%. The activity was mush higher for the material than for the conventional Koji. In Moromi mashing, starch and protein of the material were rapidly attacked by enzymes because of high solubility, resulting in the increase of the rate of material utilization. It was concluded that the processed material may be one of the potential new materials for soy sauce production.

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The mild solubilizing method of sweet potato starch granules by urea and pullulanase treatment was studied with microscopical analysis. The solubilization of starch granules by urea was more effective at 20°C than at 4°C, and at 5M urea and above, their solubility increased with increasing of urea concentration. Starch solubilized at 10M urea was about 13% of original starch and about 67% of insoluble starch in 10M urea solution was further solubilized by the subsequent treatment with pullulanase. And also, the insoluble residual fraction of approx. 20% after 10M urea-pullulanase treatment were obtained. Concentrated urea affected the structure of the starch granules. At 7M urea or higher concentrations, sweet potato starch granules swelled rapidly to 2-3 times as large as their normal size. The inside parts of them were stained blue with iodine and the outside layers purple. When these granules were washed with water they lost the blue inside parts, leaving empty granular bags of the outside layers. After pullulanase treatment of the granular bags, the core like a surface layer was obtained. A model of sweet potato starch granule was proposed.

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This report described the effects of packaging and short-time treatment with high concentration of carbon dioxide on the keeping freshness of shii-take(Lentinus edodes(Berk)(Sing.)after harvest. The period of shelf life of shii-take packed non-hermetically in a polyethylene film bag(20×26cm, 30μ thickness)was about 18 days at 1°C, 14 days at 6°C, 7 days at 15°C, and 4 days at 20°C, respectively. They should be kept at nearly 1°C immediately after harvest and the temperature for subsequent storage must be kept constant. The period of shelf life at 20°C was prolonged by the precooling treatment at 1°C for 24 hr. by a hermetical package, or by packaging with more thicker film, e. g. 80μ, compared with the above-mentioned non-hermetical package. The best packaging method to maintain shii-take freshness at 20°C storage is to exchange air for carbon dioxide and to package hermetically in a polyethylene film bag in 30μ thickness. It was also found that the short-time treatment with high conc. of carbon dioxide for about 24 hours could extend the shelf life of shii-take stored at 20°C two times as much as that non-treated one.

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This study was conducted to investigate the effect of CO₂ and 0₂ on keeping freshness of shii-take (Lentinus edodes(Berk)Sing.) under the controlled aptmoshere (CA) storage. The level of 0₂ below 2% markedly suppressed browning of the gill, polyphenol oxidase (PPO) activity and an increase of free amino acid content in shii-take. On the other hand, regardless of its levels, CO₂ strongly inhibited PPO activity and the increase of free amino acid content during storage. But under this condition fermentation took place and off-flavor was generated after 2 days at 20°C. The higher concentration of CO₂, the stronger off-flavor. Some volatiles, especially formaldehyde and ethyl alcohol increased in 100% CO₂ storage of shii-take. On exposure to air, these components decreased gradually and were not detected any more after 6 hr. At this time, browning of the gill was not observed and shelf life of shii-take was maintained. Above these results, it was found that the best condition of controlled atmosphere for keeping freshness of shii-take was at 40% CO₂ and 1-2% 0₂, and by this treatment, shelf life of shii-take could be extended 4 times at 20°C as long as that of non-treated one.

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Acid-phosphatase activity of mature-green banana fruit started to increase after a certain period of storage at 20°C and then banana fruit began to ripen. Banana fruit stored at 40°C, however, showed the decrease of acid-phosphatase activity and failed to ripen. When banana fruit was held for several hours at 40°C and transferred to 20°C, the activity of acid-phosphatase increased earlier than that of banana fruit stored at 20°C all the time. Ethylene treatment also hastened the increase of acid-phosphatase activity of banana fruit at 20°C. However, ethylene treatment at 40°C did not hasten the initiation of ripening during subsequent storage at 20°C compared with non ethylene treated control. Mature-green banana fruit which was stored at 40°C for 3 days and then transferred to 20°C, showed the increase of acid-phosphatase activity and thefruit began to ripen. But the fruit preincubated for 5 days at 40°C did not show the increase of the enzyme activity and the fruit never ripened even with ethylene treatment and 20°C storage. By means of gel-electroforcusing, seven acid-phosphatase isozymes were resolved from mature-green banana fruit and additional three new isozymes were found in the fruit ripened at 20°C. The activities of some isozymes with near neutral isoelectric point markedly increased during ripening at 20°C. However, when mature-green banana fruit was stored at 40°C, activities of all isozymes decreased and new isoenzymes found in normally ripened fruit were not detected. These results indicate that high temperature(40°C)allows to proceed an aging process before the initiation of banana fruit ripening but prevents the next aging process in which enzymes including acid-phosphatase may be synthesized and ripening of the fruit is initiated.

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The essential oils of"sumikan"(a cultivar of Citrus aurantium), "naoshichi"(C. tagumasudachi)and"yuzu"(C. junos)were analyzed by gas chromatography and GC-MS. The peak area percentages of the hydrocarbons and the oxygenated compound among the aroma constituents identified were as follows: 99.3% and 0.45% for"sumikan", 99.4% and 0.49% for "naoshichi", and 90.6% and 8.74% for "yuzu". It is suggested that it is the terpenic hydrocarbons that may largely contribute to the characteristic odour of "sumikan" and "naoshichi". Myrcene was especially predominant(24.3%)in"sumikan". The oxygenated compounds involved in"yuzu" oil much than in "sumikan" and "naoshichi" oils might deeply take part in the characteristic odour of "yuzu".

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Gelatinized rice flour(GRF)and untreated raw rice flour(URRF)were replaced with wheat flour by 20%. The changes in the fermentation properties and in sugar content of the wheat flourrice flour-yeast mixed dough during the fermentation were investigated. At the early fermentation stage, the CO₂ production of the dough containing URRF was increased, whereas in the case of the dough containing GRF, the increment was observed only at the latter stage. There were not much differences in the total sugar content between wheat flour dough and URRF containing dough during fermentation, but in the case of the dough containing GRF, it was 2 to 3 times higher than that of wheat flour dough. In the wheat flour dough, the amount of glucose decreased during early fermentation stage and that of maltose decreased only latter fermentation stage. On the other hand, the dough containing URRF had 2 to 3 times more glucose than that of wheat flour dough and the maltose content decreased during early fermentation stage. The maltose content of the dough containing GRF was 2 to 3 times higher than that of wheat flour dough during the fermentation. These results indicated that the increased CO₂ production of the dough containing URRF observed at the early fermentation stage was due to the hydrolysis of maltose by α-glucosidase derived from URRF. On the other hand, in the case of GRF, all enzymes were inactivated by the heat treatment and starch were hydrolysed only by β-amylase in the wheat flour. Therefore, the CO₂ production increased at the latter fermentation stage.

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