The growth of Hatakeshimeji (L. decastes) in submerged culture were investigated. Utilization of glucose, sucrose, peptone and yeast extract in medium was tested. Mycelial yields of the organism from sucrose were less than half of those obtained from glucose. The highest mycelial yield was obtained with C: N ratio of 12.2: 1 in the medium. The type of the mycelial growth was changed to filamentous form from pellet with decreasing the C: N ratio in the medium.

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Several workers have reported that the qualities of breads made from frozen doughs subjected to pre-fermentation for a few hours before freezing were inferior to those of breads made from frozen doughs without pre-fermentation. The causes of which have not been clearly explained to date. This study, therefore, was undertaken to investigate on the effects of pre-fermentation before freezing on the yeast viability after thawing and the following results were obtained.
The activity of the yeast in frozen dough prepared without pre-fermentation was maintained stable for twelve weeks or more. In fermented frozen dough, however, more than sixty per-cent ofthe yeast activity were lost after storage for only one week. The loss of activity was not influenced directly by the stage of the growth from resting to early logarithmic stage, but was infiuenced by the pre-fermentation products prior to freezing. When yeast was frozen in a bread dough, coexistence of the fermentation products reduced the activity of the yeast, and the reductioll was brought about more intensively with the yeast of logarithmic stage than in the yeast of resting stase.

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Comparative analyses were performed for general components in 15 types of low salted soybean miso, which were made by the replacement of a part of sodium chloride with ethyl alcohol (in 0-4% W/W concentration), as the preservative. All of these miso were prepared using the commercial enzyme preparation originated from Aspergillus oryzae.
1. Ethyl alcohol suppressed remarkably the growth of film-yeast, and in 2% concentration (W/W) inhibited completely the growth of it during the whole stage of ripening and of preservation for 90 days at 30°C.
2. Effects of ethyl alcohol on the liberation of general components were approximately similar to that of sodium chloride. That is, pH value, acidity, water soluble nitrogen and formation of color were affected by the addition of ethyl alcohol or sodium chloride.
3. Some differences were observed on the action between ethyl alcohol and sodium chloride. In the former, the ratio of the liberation of amino acid was in minor, and the concentration of direct reducing sugar and total sugar was higher than that of the latter.
These facts indicated that alcohol would inactivate some enzymes such as peptidase, and inhibit the growth of microorganism, in higher degree of their magnitude than that of sodium chloride.

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Low salted soybean miso were trially made by addition of 5% ethyl alcohol for weight of miso. Comparative analyses were performed for general components in 8 kinds of low salted soybean miso prepared using koji and commercial enzyme preparation originated from Aspergillus oryzae.
1. The contents of total acid and free amino acids and the color increased in accordance with the reduction of salt concentration.
2. Remaining activities of enzymes such as α-, S-amylase, lipase and proteases were higher in ripened miso of lower salt concentration.
3. The content of sugar in miso prepared with enlzyme preparation, was higher, but the liberation of amino acid, such as aspartic acid and glutamic acid was lower than that in koji miso. However, the contents of glutamic acid and aspartic acid were remarkably increased by decreasing the salt concentration, in both enzyme and koji miso.
4. No remarkable difference was observed in the patterns of free and bound amino acids between conventioal soybean miso and low salted one.
By sensory-tests, bitter taste was recognized in low salted soybean miso, but there were no significant difference on the taste of the miso soups which were prepared to the same concentration of total nitrogen and sodium chloride. From these results, it was discussed that bitter taste of soybean miso was suppressed by sodium chloride and bitter subatance in soybean miso Was in harmony with salt.

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Since a close relationship between enzymatic and non-enzymatic brownings is presumed, the antioxidative activity of the browning system of apple enzyme and polyphenol was investigated. Oxidation of linoleic acid was retarded by several phenols such as catechol, 3, 4-dihydroxytoluene and resorcinol. Some moderate antioxidative activity was also estimated with dopamine, noradrenaline, dopa, adrenaline or gallic acid. However, the activity was hardly observed with chlorogenic acid or pyrogallol and not with phloroglucinol or phenylalanine. On the other hand, when browning of the phenols had been induced by the action of apple enzyme, the antioxidative activity was enhanced, the activity being in the following order: 3, 4-dihydroxytoluene>catechol>dopamin>pyrogallol>noradrenaline>adrenaline>dopa>gallic acid. However, the antioxidative activity was not in- creased by the treatment of enzyme in the case of chlorogenic acid or resorcinol, even though the former is the main substrate of apple enzyme to form melanoidin and the latter itself has the strong antioxidative activity.

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Effect of amino acids on antioxidative activity of the browning system of apple enzyme and catechol were investigated. The reducing power of the system was generally increased with the addition of amino acids Which brought about enhancement of the browning. Methionine elevated the antioxidative activity remarkably, while capability of methionine in increasing power was not superior to those of the other amino acids. Enhancement of the antioxidative activity by methionine was observed at a concentration of more than half of catechol, practically optimal ratio of methionine to catechol being 0.5-1. The antioxidative activity of the browning system was divided into two fractions by dialysis. Accelerating effect of methionine was shown in the dialyzable fraction.

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In our country, cultivation of mushrooms such as Pleurotus ostreatus, Kuehneromyces nameko, and Lentinus edodes (Cortinellus shiitake) are expanding, and has reached considerable amounts. These mushrooms are cultivated generally on decaying logs of broad leaf trees. Recently, these mushrooms are also cultivated artificially on the sawdust-media containing rice bran and other nutrient in the room of which temperature is controlled. However, these artificial culture media must be germicidated for 2 or 6 hours at 100 to 120°C before inoculation of mushroom spawn.
In this study, attempts were made to cultivate Pleurotus ostreatus on the sawdust-media pasteurized by ionizing radiation. Inhibition of mushrooms growth were caused mainly by multiplication of Citrobacter and Fusarium and these organisms were eliminated by a dose of 0.5 Mrad gamma irradiation. A surprising result was that many of sawdust media subjected to 0.5, 1.0 and 2.0 Mrad increased mycelial growth rates more than heat treatments, and also mushroom yields were enhanced. The multiplication of remaining microorganisms such as Bacillus and yeasts after irradiation with a dose of 0.5 Mrad or 1.0 Mrad did not inhibit the mycelial growth of mushrooms.

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