The components of the white powder on the surface of cooked and dried sweet potatoes were investigated. The principal components of the white powder was revealed to be maltose by paper chromatography, infra-red spectrophotometry and melting point. No relation was found between the white powder and β-amylase activity of the potatoes. The white powder of better quality was found in those of less starch level which also were suitable for the production of the steamed and dried products. The amount of monosaccharide and disaccharide in the products were reduced during storage. The best temperature for the production of the white powder was around 15°C.

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Six species of yeasts and one species of bacteria were isolated from "TAKUANZUKE" (pickled raddish in the mash of rice bran and salt) in a polyethylene film bag in which fermentation was observed. One of the yeasts was identified as Hansenula anomala, two as Torulopsis sake and remaining three also belonged to Torulopsis group. The bacteria seemed to be lactic acid bacteria. Hansenula anomala and Torulopsis sake were not able to grow in 18% brine and the bacteria in 17% brine. Heat treatment was effective to prevent growth of the yeasts at 55°C for 30min., 60°C for 20min., 65°C for 10min. and bacteria at 50-55°C for 20min., 60°C for 10min. Sorbic acid was also effective to prevent growth of these yeasts and bacteria depending upon pH value and NaCl concentration of the growth media.

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The catalytic properties of crude sweet potato peroxidase preparation was investigated in comparison with those of horseradish peroxidase.
Sulfite, indoleacetate and oxaloacetate were oxidatively catalyzed with both enzymes, in the presence of Mn⁺⁺ and a monophenol, such as 2, 4-dichlorophenol. Sulfite oxidative activity in crude sweet potato peroxidase preparation was different from that of horseradish peroxidase.
When sweet potato tissue slices were incubated in ethylene (10ppm) containing air, both peroxidase and oxidase activities increased in the slices, and the ratio of oxidative activity to peroxidative activity was found to be gradually increased 24 hours after incubation.

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In the methanol extract from aerial tubers of chinese yam, dopamine (3, 4-dihydroxyphenylethylamine), catechins and associated tannins were detected by two dimensional paper chromatography.
The polyphenolic substances were adsorbed on Amberlite C G 120 resin and followed by the successive elution with pH 7 phosphate buffer solution and 3 N hydrochloric acid. From the latter effluent, a colorless crystal was isolated. The isolated crystal was identified as dopamine hydrochloride, since it had the same melting point, values of the elementary analysis, U V and I R spectrum as the latter compound.
Polyphenol oxidase prepared from the tubers of chinese yam showed high activity for the isolated dopamine. Therefore, it is likely that dopamine is a principal browning compound of the yam tubers. Other polyphenols also may take parts in the browning of the tubers.

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The phospholipids in cows milk are known to be high in unsaturated fatty acids content. Taking of this point, the authors considered that if these unsaturated fatty acids were lilerated by hydrolysis, they developed the off-flavor of milk by autoxidation. However, no study was reported concerning the presence of phospholipase in milk. The present study deals with the occurrence and the origin of the phospholipase.
(1) The presence of phospholipase was suggested by the increase of lysophosphatidylethanolamine (LPE) during the incubation of milk.(2) Addition of toluene to milk as a preservative resulted in repressing the production of LPE. But free fatty acids and LPE were increased by the incubation of milk-bacteria with milk-phospholipids. These results indicated that the phospholipase was not present originally in milk but was produced by multiplied bacteria.(3) During the incubation of milk, the increase of lysophosphatidylcholine was not observed. Therefore, this enzyme seemed to have specific activity against phosphatidylethanolamine.

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Cultured milk products from skimmilk-soy milk combinations were fundamentally studied by inoculating pasteurized samples with lactic starter cultures and measuring the acidity and the degree of curd hardness after 8hr. incubation at 30° or 37°C.
Ten per cent dispersions were heated under the 3 conditions at 63°C for 30min, 75°C for 15min, and 80°C for 5min; and then cooled. The result indicated that the viscosity raised at the range 63°-80°C, raised markedly at 80°C. Sucrose added to samples accelerated the development of viscosity, but restrained at 80°C.
With six cultures of lactic acid bacteria, after 8hr of incubation, the acid production tended to be higher in certain skimmilk-soy milk combinations than in skimmilk, exept for one culture. However, the acid production in soy milk was lower than in samples containing 70% (v/v%) soy milk. In soy milk, the acid production of Streptococcus faecalis, Streptococcus thermophilus and Strepococcus laclis increased a little. In samples supplemented with glucose, the genus Lactobacillus and Streptococcus starter cultures differed in their response to the individual skimmilk-soy milk combinations. In all cases, and in all but Lactobacillus acidophilus, sucrose did not promote the acid production of lactic starter cultures.
At soy milk concentration 20-30% (v/v%), curd after storing 24hr at 4°C was soft;on the other hand, at concentration 65-75% (v/v%), the curd structure formed was considered too hard. Addition of sucrose to 10% dispersions generally lowered the curd tensions, but glucose raised the curd tension when Lactobacillus was used.

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There are two different types of ripening method of bananas in Japan. One of them is a method using the underground-warehouse in which the fruits are heated by burning of coal gas and cooled by top ice method. This had been the major method of ripening of bananas. The other is a method using the airtight ground-warehouse in which the fruits are heated and cooled by an unit-conditioner with direct expansion or with indirect expansion systems.
The qualities of bananas processed at underground-warehouse (2.2×2.55×3.0m; temp. 17-21°C, R.H. 82-95%, C2H4 4400-4700ppm) were compared with those of fruits from ground-warehouse (3.7×6.15×4.0m; temp. 14-19°C, R.H. 80-90%, C2H4 2950-3250ppm). It was found that the increases of sucrose content and of titratable acidity in bananas processed at underground-warehouse were more rapid than those in fruits processed at ground-warehouse during ripening period. The fruit qualities from underground-warehouse were better organoleptically than those of fruits from ground-warehouse during storage.

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