Irradiation of the samples of fried bean curd which have been packed in polyethylene film (PEF) under reduced pressure with total doses of 8 and 40×10⁴γ was found to be effective in prolongation of storage period at low temperatures. The latter irradiation dose was also found to be effective for preservation at 25°C.
A slight irradiation odor was noticed with those which received40×10⁴γ dose but it became undetectable on cooking. The cooked irradiated samples were found to be not significantly different from control samples in appearance and taste.

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The organic solvent-soluble fraction of the irradiated samples showed a slight increase in peroxide value, carbonyl, and absorption in the ultraviolet region. No radio-activity was detected, within the sensitivity of the method of detection employed, in the ashes of the samples irradiated with a total dose of 4×10⁵r.

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The irradiated samples were found to show no significant changes in non-protein-nitrogen, amino-nitrogen, volatile nitrogenous bases, and total-nitrogen. Those which received a total dose of 4×10⁵r liberated the sulfhydryl group, but not mthyl mercaptan. The method of analysis employed failed to detect volatile acids in the irradiated samples, but further study is necessary from the standpoint of correlating the observed chemical changes with the radiation odor.

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In our previous paper, it was reported that the L-ascorbic acid-L-histidine system gave the characteristic color product in the aqueous solution.
In order to make a further research of the browning mechanism, the effects of pH, several kinds of metalic salt, thiourea and sucrose on this system were investigated; and also, the chromatographic studies on the colored solutions were carried out.
The results of these experiments were as follows:
1. The most remarkable color development in this system was observed at the stage of pH 6-8; and also, the color development in the dehydroascorbic acid-L-histidine system was similarly remarkable at the same stage of pH.
2. The browning of this system was accelerated by Fe and Cu (chlorides), considerably, inhibited by Sn, Zn, Mg (chlorides), thiourea and sucrose, and almost perfectly inhibited by N₂ or H₂.
3. The hydrolysates of these colored solutions gave two ninhydrine-positive spots in addition to that of L-histidine in the paper chromatography.
This fact seems to suggest that L-histidine is immediately responsible for the browning mechanism of these systems.

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It is desirable to utilize the chlorella not only for a resource of food protein but also for the resources of pigments such as chlorophyll, carotene, and of others.
For this purpose, the butanol treatment was the most available technique, by this, proteins, pigments, and the other soluble materials were isolated simultaneously. The treatments such as the grinding with sand, freezing with liquid air, and autolysis with toluol could raise the yield of extractable nitrogenous materials.

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The protein, so called “extractable protein”, was isolated from 4.7kg.of fresh scenedesmus by the autolysis-grinding-butanol method. This protein, 96g.in dry weight corresponding to. 18 per cent of the true protein of scenedesmus, had a light greenish white colour.
The studies on the nutritive value and amino acid composition of this protein are in progress.

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Digestibility was determined by the method of trypsin digestion in vitro, and by the Mitchell's method with rats in vivo. The values obtained with the proteins isolated from chlorella or scenedesmus were much higher than that obtained with the dried chlorella (scenedesmus) or decolored one. They can match with casein in digestibility.
The biological value of the isolated protein, however, was somewhat lower than that of casein. But the isolated protein is available to use to the improvements of nutritive values of cereal proteins, for example, the improvement of nutritive value of bread by the addition of the isolated chlorella protein was explained by the circular explanatory diagrams of limitting amino acids.

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Supplementing the casein diet with 0.8% nitrogen content with 0.2% each of L-lysine and DL-threonine or 0.2% DL-threonine alone showed some effects in body weight and the xanthine oxidase activity of liver of rats but did not show much effect. The effect of the same amount of L-lysine and DL-threonine to the same casein diet which has been supplemented with 0.2% DL-methionine was not also observed.
From the above observations it was considered that the effect of supplementing 0.2% each of L-lysine and DL-threonine to the dried mixed diet of 0.8% nitrogen content which was previously must be the complementary effect of these amino acids rather than the specific effect known for threonine in the case of the casein diet of low protein level.
On the other hand, significant increases in body weight of rats were observed when supplemented with 0.2% each of L-lysine and DL-threonine in addition to 0.2% each of DL-methionine and DL-tryptophan to the casein diet. The rats on the casein diet did not show fatty liver but those given the same diet supplemented with 0.2% DL-methionine.

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Hydrolysis of globulin and glutelin prepared from eighteen kinds of leguminous seeds afforded the mixtures of fourteen kinds of amino acids, which were identified by paper chromatography, respectively, as aspartic acid, glutamic acid, serine, glycine, lysine, threonine, alanine, arginine, histidine, valine, phenylalanine, leucine, proline, and tyrosine.
Each of these amino acids was estimated by the procedure recommended by J.Awapara.
As shown in Table 2, a relatively larger amount of lysine was found to be present in globulin and glutelin prepared from kidney beans, whereas a relatively minor amount of threonine present in globulin and glutelin prepared from peanuts.

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The content of hemoglobin and myoglobin in meat-beef, horse and whale-as estimated simultaneously by the spectrophotometry on the extract saturated with carbon monoxide. Hemoglobin and myoglobin were extracted from the homogenized meat with acetate buffer pH 4.5 as described by de Duve. The absorption spectra of the mixtures of carboxyhemoglobin and carboxymyoglobin were plotted by Beckman DK self-recording spectrophotometer or Hitachi EP U-1 spectrophotometer. The content of hemoglobin and myoglobin was obtained from the absorbancy at 560, 570, 576 and 580mμ by the nomograph made by Tsushima and Okazaki.
The rate of hemoglobin and myoglobin was also calculated by other methods such as that of de Duve and that of Poel. The sum of these proteins was also checked by cyanide-methemoglobin method.
The rate of hemoglobin and myoglobin as observed to remain constant in spite of the difference of the animal species and the localization in the body, accordingly in spite of the difference in the total content of the extractable heme-proteins. The content of hemoglobin was estimated to be approximately 10% of the total heme. No remarkable difference in the hemoglobin content was observed between whale and the other meat, although some difficulties in removing the blood might be conceivable in the former.
The hemin content of dark muscles of bonito and tuna was also determined.

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Sodium and potassium contents were determined by flame photometry for about seventy sorts of food which were consumed preferably for low-sodium diet.
Sodium content of about twenty sorts of cooked diets was estimated and compared with that of calculated data

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It is necessary to know the requirements of N, Ca and P for fetus in order to discuss about the metabolism of these elements during pregnancy.
Since the amount of each chemical component contained in the fetus could be considered as his requirement for these nutritional elements, it is possible to determine the fetal requirement during pregnancy by analyzing the chemical component of the fetus at each lunar month.
The author attempted the analysis of chemical components on 24 fetuses varying from the third gestation month to the mature newborn and followed up the requirements of N, Ca and P in accordance with the gestation month.
In the meantime the quantitative relationships of N, Ca and P were observed on the fetus which was divided into the skin, supportive, and soft tissues, and on the fetal attachments.
The results of the experiment were summarized as follows;
1) The average amounts of N, Ca and P for the Japanese mature newsborn were 18, 7.24 and 3.81g/kg, respectively.
2) The accumulation of N. Ca and P in fetus is notable at the third trimester, especially during the last two months of pregnancy. The average daily amount of these elements accumulated in fetus raises as the pregnancy advances.
3) 55% of N, 60% of Ca, and 57% of P, were accumulated in the fetus during the last two months of pregnancy.
4) 96-98% of Ca, 87-75% of P in the fetus were contained within the supportive tissues, and the amount of Ca in the fetal attachments was only 1.5% of that in the fetus.
5) The ratio of Ca to P in the supportive tissues of fetus from the fifth month to mature newborn show its peak at the eighth month and remained almost constant thereafter.

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There are many reports on the relationship between the time necessary for clotting of milk in vitro by pepsin, papain, or rennin and the firmness of curd formed in vivo, and also on the fact that the longer this time is, the better the digestivility of the curdis.
The influence of various preparations or additives on the clotting time of dried skimmed milk solution by pepsin was investigated.
Following results were obtained:
1) clotting time was lengthened by a longer mixing or boiling time.
2) the addition of saliva to liquid milk lengthened the clotting time, the addition of salts, on the contrary, shortened, sugar did not show the decided results

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Summary of the results of an experiment concerning the oxidation of vitamin C inMomijioroshi is as follows.
1) Edible vinegar hastens the autoxidation of vitamin C in Momijioroshi, but inhibits enzymic oxidation, while Shoyu (Soy-bean sauce) inhibits the both actions. Na-glutamate, used as seasoning, prevents the autoxidation, but is inert to enzymic oxidation. Addition of one part of a mixture of Shoyu and edible vinegar (the ratio 9: 1) to five parts of Momijioroshi gives rise to marked inhibition of both autoxidation and enzymic oxidation and loss of vitamin C is exceedingly small even after three hours.
2) L-glutamic acid strikingly inhibits the autoxidation of vitamin C, followed by L-asparaginic acid. Prevention of ascorbic acid autoxidation by Shoyu and Na-glutamate is considered to be due to such reasons.
3) As the preparation of Momijioroshi is the most adequate method to eat fresh radish, carrot, etc.raw, it will be highly desirable that the grated radish and carrot are mixed together after separate addition of the condiment and are served at table and thereby can prevent the loss of vitamin C.

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The rice produced in Vietnam, Thailand, Burma, Hainan Island, Philippine, Celebes and Java was analysed, with polished or unpolished one. The vitamin B₁ contents were also determined and were found to be somewhat lower than that of ordinary rice produced in Japan, with an exception of those produced in Java and “Horai” rice in Hainan Island.

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The effect of heat treatment at100°, 110°, and130°C with water and at 105°and 150°without water on the nutritive values of the proteins of kidney beans, green peas, andpeanuts was studied by measuring the digestibility and the liberated amounts of methionine, cystine, and lysine, as the nutritive limiting factors, after the digestion with pancreatine.
The results were as follows:
1) On the green pea-and peanut proteins, the highest digestibility, was shown inthe case of the raw materials, and this was followed by the materials heated at 130°Cwith water. Meanwhile, on the kidney bea, ns, the reverse was shown.The materialsheated at 150°C without water showed the lowest digestibility.
2) The materials heated at 130° and110°C with water showed the highest liberationof methionine and cystine.
3) On the liberation of lysine, the highest value was shown by the raw materials and the lowest by the materials heated at 150°C without water.

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The effects of heat-treatment of soybean and green pea under practical cooking conditions, namely, 1) boiling, 2) parching, 3) steaming, 4) frying in oil, and 5) boiling inthe pressure cooker, on the digestibility of protein and the liberation degree of methioninewere studied. In the digestion experiments, pancreatine was also applied.
In these treatments, frying in oil showed excellent results in digestibility and methionine liberation.

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Ethyl ester of linolenic acid was prepared by the bromination method on the acidseparated from linseed oil.By heating this ethyl ester in a CO₂ stream at 250°C for 40 hours, polymerized ethyl linolenate was produced.
This product shows toxicity to rats. Cyclic ethyl ester was separated from polymerizedethyl linolenate by the urea adduct-forming method, and adistillable esterportion (153-175°C/1.8-2.0 mmHg) was separated from this cyclic ethyl ester by vacuumdistillation. This distillable ester shows extremely acute toxicity, and seems to be themain source of the toxicity of the polymerized ester.
Judging from its general property, molecular weight, and infrared absorption spectrum, it is supposed that this distillable ester is a cyclic monomer, and that it conteins a tompound whose molecule has a cyclohexene ring.

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In the previous papers of this series, it was reported that the cyclic monomer obtainedby vacum-distillation of the cyclic ethyl ester separated from thermally polymerizedethyl linolenate shows acute toxicity, and that this cyclic monomer seems to be the mainsubstance responsible for the toxicity of the polymerized ester.
It was also assumed that this cyclic monomer contains, as its main component, a compoundwith a cyclohexene ring in its molecule.
Experiment was conducted on the toxicity of a synthesized compound which has acyclohexene ring, and which has almost the same molecular weight as the cyclic monomerseparated from thermally polymerized ethyl linolenate.
Toxicity of this and also other cyclic compounds to rats was studied.

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