An unpleasant odor was produced from the water extract of pork mixed with iron powder (extra pure grade) at room temperature. A main conponent of the unpleasant odor was found as H₂ S which might possibly play an important role in enhancing the odor of other components. To investigate the formation mechanism of H₂ S, various amino acid, amine and carbohydrate solutions were used, and remarkable rates of H₂ S were found to be formed from cystine, cysteine, histidine monohydrochloride, citric acid and Na2 EDTA solutions by interacting with iron powder, respectively.
As hydrogen sulfide was formed not only from sulfur compounds, but also from non-sulfur compounds interacted with iron, it was interpreted that a part of precursor of H₂ S might be the sulfur component contained in iron powder as impurity.

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The development of swelling of rehydrated Kori-tofu was studied. The results obtained were as follows.
(1) The development of swelling of rehydrated Kori-tofu occurred with the removal of ammonia held in Kori-tofu into rehydration solution.
(2) Ammonia fixed in Kori-tofu treated with ammonia gas and stored for a long time, became non-soluble, and couldn't take part in the swelling of Kori-tofu as rehydrated.
(3) When Kori-tofu was rehydrated with several kinds of alkali solution (NH4 OH, NaOH, Ca(OH)₂), it swelled with the increase of the concentration of the solution (beyond 0.1M), and beyond pH 9.
(4) Kori-tofu swelled in the alkaline solution showed shrinkage with the addition of acid to it, but its volume was ever larger than that of rehydrated Kori-tofu as control. This will be the reason why it doesn't shrink when treated with water in cooking.
(5) Ammonia treated Kori-tofu, from which most of ammonia liberated with its long storage, swelled similarly by repeated treatment with ammonia gas.
(6) No significant differences were recognized between proteins in ammonia treated Kori-tofu and the control, as observed from the result of SH group and the digestibility with pepsin.

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In the previous paper, it was reported that the clarifying activity of the commercial pectinase preparation for citrus juice was caused by the joint action of polygalacturonase and pectinesterase, and pectinesterase activity was more effective than those of any other enzymes for the clarification. But, it was found in this study that a fraction which was free from polygalacturonase and pectinesterase activities in commercial cellulase preparation contained an accelerating factor for the clarification.
This factor has a property of hydrolizing hemicellulose. The result suggests that the accelerating factor is a certain kind of hemicellulase. This hemicellulase has more acid stable and more thermostable characters than other enzyme preparations which have no accelerating property. Hydrocellulase also showed an accelerating effect for clarification, but its detailed role has not been revealed exactly.

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Quantitative determination of organic acids in "Shottsuru" (fish sauce) was done by means of a partition chromatography using silica gel and the changes in the amounts of organic acids were observed through the process of ripening.
Eleven kinds of organic acids which were butyric, iso-butyric, propionic, acetic, oxal-acetic, pyruvic, fumaric, succinic, lactic and pyro-glutamic acids were confirmed in "Shottsuru".
"Shottsuru" prepared in a longer ripening period contained much more organic acids than that in a shorter ripening period.
Iso-butyric acid and acetic acid were about 30% of total organic acids respectively.

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Volatile fatty acids (VFA), alcohols, amines and carbonyl compounds which were produced from the 3-sn-phosphatidylcholine by autoxidation, were examined by gaschromatography and thin layer chromatography. On the VFA, amines and alcohols, the following compounds were characterized; acetic acid, iso-butyric acid, butyric acid, trimethylamine, ethanol, butanol, iso-amylalcohol, etc. The quantitative analysis of carbonyl compounds gave 87.0% of saturated and 13.0% of unsaturated carbonyls. The following compounds of saturated carbonyls were detected; n-ethanal (36%), n-propanal, n-butanal, n-hexanal, 2-pentanone and 2-nonanone. Though two fractions of unsaturated carbonyls could not be identified clearly by the reason of their unstability, one of them was considered to be 2-propenal (acrolein).

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The separation and determination of L-ascorbic acid (AA) and erythorbic acid (EA) in foods were inverstigated by paperchromatographic method. EA was not recognized in natural foods, but detected in some canned foods in which EA was added as an antioxidant. The amount of AA determined by this method in commercial AA-enriched canned fruits and other canned foods was over the labeled level on the contents.

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Thirteen samples of commercial soybean flour and isolated soybean protein were analyzed to determine the range of moisture, protein, fat, ash and carbohydrate content. In general components there was large differences between 13 samples, the protein and fat content of the samples varied 32.5-68.8% and 0.1-15.7%, respectively.
The effect of pH value between 6.0 and 9.0 on the solubility of soybean flours was examined by the similar method to non-fat-dry milk. Exposure of soybean flours to sodium hydroxide solution at high pH levels (pH 8.8) markedly increased its solubility. This solubility of soybean flours was in good agreement with Nitrogen Solibility Index (NSI).
Furthermore, yoghurt-like-products prepared from soybean flour were determined for the hardness and texture. The low level soybean flours of solibility and NSI that were added in yoghurt-like-product formed yellow precipitate, granular texture and increased soybean flavor.
Solubility and NSI measurement would be a useful key for selection of soybean flour suitable for yoghurt-like-product.

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