Two types of pectinase inhibitor, the soluble one and the inhibitor linked to tissues, were separated from apple flesh. The present report relates to chemical properties of the latter and mechanism on the pectinase inhibition.
1) The inhibitor was nondialyzable and very stable against heat treatment, easily eluted from the tissues by treatment with 75% ethyl alcohol or a solution of commercial pectinase preparation. The eluate prepared under anaerobic conditions showed no inhibitory action on pectinase activity.
2) The inhibitor precipitated the pectinase by forming a insoluble complex. The inhibition mechanism was considered from studies on the mode of their interactions.
3) The inhibitor was easily removed by adding an appropriate amount of gelatin, nylon powder or hide powder owing to the specific properties to combine with them. Similar reactivities were observed with oxidized and polymerized product prepared by acting apple polyphenoloxidase on chlorogenic acid. The ultraviolet and visible spectrums of the former were similar to those of the latter.
4) No significant difference was observed in ability to inhibit the pectinase action between the inhibitor and tannic acid. The oxidized product prepared from chlorogenic acid was the most powerful inhibitor, whereas chlorogenic acid itself showed no inhibition.

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Adult rats were fed on a protein free diet for 0, 2, 4, 8, 16 and 30 days. The amounts of ribonucleic acid, deoxyribonucleic acid and nitrogen were determined in skeletal muscle and liver.
During the experimental period, the total amount of deoxyribonucleic acid in muscle remained constant. The amounts of ribonucleic acid and nitrogen in muscle were gradually decreased, and the change in the amount of ribonucleic acid of muscle was followed by the change in the amount of nitrogen. But in liver, the amounts of RNA and nitrogen were markedly decreased in the initial period and then tended to level off.

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Rice plants before harvest were subjected to artificial rain fall (1) in the daytime, (2) in the night-time and (3) for a whole day and night, and the changes of the physical and chemical qualities of rice were investigated. The treatment was performed (1) immediately before harvest, (2) a week before harvest and (3) two weeks before harvest.
Moistening immediately before harvest lowered the water soluble dry matter content, the sugar content and the pH values, especially in the rain fall treatment for 24 hours. From these data it appears to be reasonable to conclude that moistening just before harvest causes the deterioration of the physical and chemical qualities of rice.
The electric conductivity of rice subjected to rain showed smaller values than that of untreated rice, the smallest value being obtained in the rain fall treatment performed two weeks before harvest. This was probably caused by the loss of the electrolytes like potassium ion from rice kernels from rain fall.
The α and β-amylase activities of rice were increased with the rain treatment. From a consideration of the decrease in the amounts of water soluble dry matter and sugar of rice by the rain treatment in spite of the increase in the activities of these enzymes, it is assumed that the amount of degradation and consumption of sugar exceeded the amount of sugar formation.

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In Japan, the conventional form of rice storage is husked brown rice which is consumed within a short term after milling not longer than one month.
The storage deterioration of n-hexane-treated milled rice was investigated in contrast with brown rice in respect of flavor, aroma, taste, appearance, and rheological properties including cohesiveness and hardness. It was found that n-hexane-treated milled rice had better keeping quality than brown rice. Even in short-term storage, the deterioration of n-hexane-treated milled rice was less than that of conventionally milled rice. Practically, the former had better cooked rice flavor than the latter when stored for 2-4 weeks, as is the case in common practice at home, at room temperature in summer.

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In order to examine the change of peptides in the TCA soluble fraction in the cource of natto manufacture, the TCA soluble fraction was seperated into an adsorbed and unadsorbed component by ion-exchange chromatography (Dowex 50W-X2), and the former was seperated according to moleculer size by means of dextran gel filtration (Sephadex G-10).
1) The fraction which was adsorbed to Dowex 50W-X2, that is-smaller size compounds, was 78-93% of the total, and its proportions in the total were lower in raw soy-bean and steamed soy-bean (group A), and higher in natto (group B). The unadsorbed fraction, that represents larger size compounds, was 2-9%.
2) Gel filtration profiles in Sephadex G-10 column resembled closely similar in the same group, but there was a great difference between A and B. The pattern of group A has two peaks (I, III) and group B has three peaks (I, II, III). Peka I comprised peptides of about 1, 000 molecular weight, peak II dipeptide, and peak III mostly amino acid.
3) The results suggested that during fermentation larger size peptide which was unadsorbed to Dowex 50W-X2 decreased, and smaller size peptide which was adsorbed to Dowex 50W-X2 increased, above all dipeptide markedly increased.

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The oligosaccharides in some legume seeds were determined by means of quantitative paper chromatography followed by aqueous extraction and colorimetry with phenol-sulfuric acid method (Table2). Non-starchy legumes (Arachis hypegaea and Glyciue max) contained sucrose and α-galactosylsucroses as the major oligosaccharides. In starchy legumes the next highest oligosaccharide was the most abundant. It was stachyose in case of Phaseolus chrysanthos, P. vulgaris, Vigna sesquipedalis, and Canavalia gladiata, while it was verbascose in case of Vicia faba, Pisum sativum, and Phaseolus aureus. This means the former four legume seeds contained verbascose, while the latter three legume seeds contained ajugose. The view of Courtois and Percheron⁴⁾ on oligosaccharides of Vicia and Lens culinaris has now been confirmed at least with those seven starchy legume seeds examined.

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An investigation on the joint effects of some food additives promoting the formation of cured meat color and being employed in processing meat products, and some metal ions naturally occurring in meat on the behavior of nitrite was undertaken by determining nitrite by a colorimetric method proposed in the previous paper.
The results obtained are as follows:
(1) The decomposition of nitrite was fairly promoted by the addition of Na-ascorbate, Na-iso-ascorbate and Fe²⁺, respectively, and particularly in the case of Fe²⁺, a significant decomposition of nitrite took place at pH 6.0 as well as at pH 5.0.
(2) It was found that all the test additives tended to promote the decomposition of nitrite in the presence of Na-ascorbate and this tendency was more remarkable at pH 5.0 than at pH 6.0.
Among the additives tested, both of Fe²⁺ and Fe³⁺ were the most efficient in promoting the decomposition of nitrite, which was considerably accelerated by heat treatment at pH 6.0 as well as at pH 5.0.
(3) Na-ascorbate was found more effective than Na-isoascorbate in accelerating the decomposition of nitrite.
The difference in the effect between the two reductants was more clearly shown when the test solutions were cooked for one hour at 75°C after being kept for 72 hours at 4°C.
(4) The effect of nicotinamide on the behavior of nitrite was tested by manometric techniques.
The results indicated that the addition of nicotinamide significantly promoted not only the decomposition of nitrite but also the formation of nitric oxide from nitrite in the presence of Na-ascorbate.
The fact that nicotinamide has promoted the evolution of nitric oxide which is indispensable to the formation of cooked cured meat color, may explain the promoting effect of nicotinamide on the color formation of cured meat products.

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Dry mature food legumes examined were 1) Arachis hypogaea, 2) Vicia faba, 3) Pisum sativum var. arvense, 4) Phaseolus chrysanthos, 5) P. aureus, 6) P. vulgaris, 7) Vigna sesquipedalis, 8) Canavalia gladiata, and 9) Glycine max. The so-called nitrogen-free extract was calculated (Table 1). Since the nitrogen factors for various legume seeds are not yet determined, the values may be smaller (cf. Table 5). Free sugars, starch, and pectic substance were determined by conventional methods (Table 2). It was found that the pH was important in relation to precipitate calcium pectate (Table 3). Crude fiber was fractionated into α-, β-, and γ-cellulose (Table 4). It is very difficult to know the content of the so-called hemicellulose (cf. Table 5).

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It has been well known that the contents of sulfhydryl and disulfide groups correlate with the physical behavior of dough in bread making, and also that the sulfhydryl and disulfide groups are the precursors of sulfur compounds in food volatiles. Therefore, it is conceivable that the functional group play an important role in the food flavor from the view point of both texture and aroma.
Then the contents of sulfhydryl and disulfide groups of six kind of milled rice were estimated amperometrically by using silver nitrate titration. The contents of sulfhydryl groups were 0.77-1.47μeq/g of rice and those of disulfide were 1.43-2.39μeq/g of rice.
The rice having good palatable qualities like fresh rice or domestic rice were rich in sulfhydryl contents, compared to old rice or foreign rice, respectively. The sulfhydryl groups of milled rice, therefore, must be taken consideration for the discussions of cooked rice flavor.

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A procedure for the quantitative estimation of mono- (MG), diglycerides (DG) and propylene glycol mono fatty acid esters (MP) in margarine and shortening was studied.
After the esters was cleaned up by thin layer chromatography, they were estimated individually by programmed temperature gas chromatography. In this procedure cholesterol was added to the sample as internal standard.
Samples with known quantities of MG, DG or MP were analyzed, and recoveries of them were about 97-105%.
Several commercial samples of margarine and shortening were analyzed by the proposed method, and results obtained as follows: MP was not detected in any sample, but MG and DG were detected in most samples, and quantities of them were different from one another; total quantities of them in margarine were from trace to 2.2mg/100mg, and those in shortening were from trace to 7.1mg/100mg.

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