The relation of chemical methods to an organoleptic method using various edible oils which were oxidized by the active oxygen method, was investigated. As the results, it was revealed that total and steam distilled carbonyl values which were calculated as saturated carbonyl and monoenal are the most recommendable indicators for the rancidity of the oil followed by peroxide value, while TBA and acid values are not suitable as the indicators.

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The factors such as proportion of basic ingredients, particle size of rice flour and the ratio of rice flour to cornstarch were investigated on their effects on the qualities of the rice flour butter cakes.
Among 27 kinds butter cakes made from basic ingredients of different amount, the cake in the following proportion of basic ingredients was the best in quality and the degree of transformation to α-type starch was 95.2%: rice flour 100 parts, sugar 100 parts, eggs 106 parts, shortening 63 parts and water 17 parts.
When partick size of rice flour was smaller than 120 mesh, the cake was softer and more palatable.
Since the employment of cornstarch to substitute 25-50% of the rice flour resulted in the reduction of the taste, it is advisable to use rice flour only.

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The possibility of purity analysis of Citrus Unshiu juice by means of the carotenoid pattern has been examined.
Investigations of carotenoid pattern of several citrus fleshes showed two typical pattern; one was the Naruto orange type which contained about 50% of diol diepoxid and the other was Unshiu type in which monol carotenoid occurred in amounts of 70% or more.
The carotenoid pattern of commercial mature green Unshiu flesh was identical to the pattern of general Unshiu fleshes at immature stage. Carotenoid patterns of mature Unshiu fleshes which obtained from eight main growing districts indicated that the fleshes contained 2mg% or more of total carotenoids and 70% or more of monol plus monol monoepoxide carotenoids and 10% or less of hydrocarbon carotenoids regardless of growing area and varieties.
The carotenoid pattern of ten commercial samples of canned straight juice were quite similar to that of raw materials "Citrus Unshiu."
These results suggested the applicability of carotenoid pattern for the purity analysis of Citrus Unshiu juice.

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In a previous paper, the authors reported that phospholipase was not present originally in cows milk but produced by multipling bacteria.
This paper is concerned with the separation of phospholipase producing bacteria from precultivated milk and their cultivation in a medium of egg yolk agar or blood agar. The most active phospholipase producing bacterium, Enterobacter aerogenes, was separated, and the general properties and specificity of the enzyme of this bacterium were studied.
The results obtained are as follows: (1) Optimum temperature is 38-40°C. (2) Optimum pH is 7.0-7.3. (3) This enzyme has the phospholipase activity against phosphatidylethanolamine, phosphatidylserine and phosphatidylcholine, but not active against sphingomyelin. (4) This enzyme is presumed to be an induced enzyme because of the phospholipase activity in enzyme preparation which can be noted only when phospholipids are added into a medium. This activity can not be found in the enzyme preparation made from a phospholipids-free medium.

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As the previous report, that tannin was precipitated by methyl cellulose, expected the similar effect with other polyethers, the precipitation of tannin with soluble and synthetic polyethers, i.e. polyethyleneglycol (M.W. 200-20, 000), polypropyleneglycol (M.W. 400-2, 000), polypropyleneglycol ether of trimethylolpropan (M.W. 300-4, 000) and glycerin (M.W. 3, 000), and some surface active agents were studied.
The effects of pH, temperature, and co-existence of other substances on the precipitation with polyether are similar with case of metyl cellulose. The precipitation is under the rule of concentration ratio of tannin to polyether. The heigher the molecular of tannin is, the lower the molecular of polyethyleneglycol need to precipitate and the larger precipitation ratio with same polyether is. Among many polyethers, polyethyleneglycol have the strongest activity of precipitation.
Therefore, the precipitation ratio with polyethyleneglycol (M.W. 1, 000) is in the proportion to the molecular of tannin. Polyether did not precipitate low molecular polyphenolics, catechin, chlorogenic acid, and anthocyanin, but was able to remove completely the astringent tannin from fruit and vegetable juices. Among surface active agents, Tween which contained polyethyleneresidue, also precipitated tannin.

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To clarify the cause of the abnormal flavor of citrus fruits in the wax treatments and in the CA storage, internal oxygen levels and ethanol contents of Natsudaidai fruits were determined.
In the cold storage for 33 days at 4°C, internal O₂% of the central space was 18.7%, and 15.8% in the segments. After transferred to the room temperature, O₂% in the central space decreased rapidly and then gradually increased, but in the segments, gradually decreased. Wax coatings, film and shrink wrappings decreased the O₂% in the central space and in the segments, and developed the strong abnormal flavor. High ethanol contents were found in the fruits with the abnormal flavor.
The ethanol accumulation due to the low oxygen levels inside the fruits seemed to cause the abnormal flavor in CA storage and in the waxed fruits.

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