The volatile substances stripped from crushed sporophorus of Lentinus edodes were analyzed by chromatographic procedures. Three of 8 major components behaved as carbonyl compounds; 2 of them were identified as acetaldehyde and propionaldehyde, respectively, and the remaining one appearing to be a sulfur-containing unsaturated aldehyde was left unidentified. Five sulfur compounds were also detected in the stripped volatiles; 3 of them were characterized as methylmercaptan, methylsulfide, and dimethyldisulfide, respectively; all of which appear to contribute significantly to the flavor the crushed mushroom bearing. Free formaldehyde contents in fresh and dried mushrooms were measured colorime-trically after the dimedone-chromotropic acid reaction. In any case formaldehyde contents were found never to exceed above 40μg per g of the mushroom on dry weight basis. On contrary, a significant amount of formaldehyde was found to be evolved on refluxing the mushroom extracts in 2% phosphoric acid, i. e. under the conditions that were much the same as those of steam distillation adopted in the official methods of analysis for formaldehyde. Evidences were given for evolution of formaldehyde via an acidic decomposition of lentinic acid during the refluxing procedure.

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From ninety to ninety-five percent of anserine and carnosine in rat gastrocnemius were able to extract under a very mild condition (0°C, 0.9% NaCl). The remnant was extractable by the treatment of 80% ethanol at 60°C. When the excess dipeptide was incubated with a supernatant solution of 12, 000 X G of 10% muscle homogenate, 20% of additional dipeptide was found in a protein fraction which was separated by Sephadex-G25 column. When the dipeptides were displaced by a physiological concentration of the tritiated dipeptides in the above experiments, 8.3 X 10^-3 μmole/dl of anserine and 8.4 X 10^-3 μmole/dl of carnosine in serum and 0.49 X 10^-3 prnole/g of anserine and 0.43 X 10^-3 μmole/g of carnosine in liver were found in a certain protein fraction. Moreover, the dipeptides originated from an article of animal food (meat) were very stable against the agitation for 1 hr at 100°C under a model condition such as cooking procedure (recovery rate; 100%).

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In order to investigate the relation between lipid content and the storage deterioration of rice flavors, the milled rice was treated with n-hexane to prepare the samples having various lipid contents. The results are summarized as follows.
1) Flavor of cooked rice was not affected by n-hexane treatment, even though the lipid was removed to the extent of 0.08% by the treatment.
2) After storage at 30°C or 40°C for 1 month, it was found that the degree of storage deterioration of milled rice was almost proportional to its lipid content. That is, the smaller the lipid content, the less the flavor deterioration during storage.
3) The texture changes during storage were measured with texturometer. Highly significant negative correlation was found to exist between adhesiveness or H/A (hardness/adhesiveness) of texturometer parameter and hardness or cohesiveness of sensory tests. The effect of lipid content on the storage deterioration in texture was also confirmed with texturometer measurement.

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In a previous paper we reported that the diet containing 5% of ground dried mushroom (Lentinus edodes) and 1% cholesterol markedly reduced plasma cholesterol levels in rats.
To elucidate the reducing mechanism of plasma cholesterol by mushroom, neutral sterols and bile acids excreted into feces were determined. The results obtained were as follows.
(1) Neutral sterols in feces fed mushroom were increased, however, bile acids were not increased compared with control group (mushroom-free diet).
(2) Total amounts of cholesterol in whole body fed mushroom were less than that of control.
These results indicate that the reducing effect of mushroom is due to the increasing excretion of administered cholesterol.

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Twenty four male Wistar rats weighing about 100g. were separated into four groups. A semisynthetic diet was administered to each group and hydrogenated cocoanut oil was used as the source of fat. Group 1 was given a basal diet, group 2 a basal diet supplemented with 1% cholesterol and 0.2% cholic acid, group 3 a basal diet supplemented with 0.25% S-Methylcysteine Sulfoxide (Methiin), 1% cholesterol and 0.2% cholic acid. A diet which contained 0.5% Methiin, 1% cholesterol and 0.2% cholic acid was administered to the fourth group. After two weeks of this dietary regimen the animals were killed by decapitation. The blood, liver and aorta were removed immediately and portions of these tissues were examined to determine cholesterol and phospholipid levels.
The blood cholesterol level in rats fed 1% cholesterol added diet was elevated to approximately 500 mg/dl. (group 2) and supplementation of Methiin to the cholesterol diet depressed this elevation significantly. In contrast, phospholipid levels revealed no significant change in the experimental groups. Total cholesterol of the liver decreased significantly by the addition of Methiin to hypercholesterolemic diet but free cholesterol in liver and total cholesterol in aorta revealed no significant change. This effect of Methiin concerning nutrition of vegetables showed the given consideration.

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The present paper is concerned with the changes in nitrate content and nitrate reductase activity of carrot plant during the periods of growth and post harvest storage. Nitrate content of carrot plant was higher in petioles than in the other parts of the plant during the period of growth. In the middle stage of growth, the nitrate content in petioles was three times greater as much than in leaflets and six times as much than in roots. Activity of nitrate reductase was higher in leaflets than in petioles or in roots.
Nitrate content of carrot plant harvested at younger stage and at commercial harvest-stage showed no change during storage except for a little decrease in petioles. Nitrate reductase activity in leaflets during storage showed a marked decrease in the early period of storage and gradually decreased there-after, but no change in the activity was found in petioles and in roots during storage.
Under the condition of controlled atmosphere (CO₂=3%, O₂=3%) at 0°C, the content of nitrate in carrot roots was smaller than under the atmospheric condition in the earlier period of storage, but there was no difference in nitrate contents in such treatments in the latter period of storage.
The ascorbic acid contents of carrot plant during growth and post harvest (storage) periods were also determined with reference to the change in nitrate content, but there was no correlation between contents of the two compounds.

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In the processing of meat products, various food additives are being used. In an effort to clarify the mechanism of the formation of cooked cured meat color in case, an investigation was performed with an aqueous model system as to the effects on the behavior of nitrite, of some food additives usually employed in processing meat products by means of a colorimetric method for nitrite determination which was proposed in the previous paper.
The results obtained are as follows:
(1) The food additives tested generally exercised more striking effects on the behavior of nitrite in test solutions of pH 5.0 than in those of pH 6.0.
(2) Most food additives tested were found to exhibit a tendency to promote the decomposition of nitrite in the presence of sodium ascorbate, whereas nitrate, tripolyphosphate and hexametaphosphate tended to inhibit to a certain extent the decomposition of nitrite in the presence of ascorbate.
Pyrophosphates initially inhibited the decomposition of nitrite in the sample solutions containing sodium ascorbate, however, after being kept for 72hours at 4°C, they apparently promoted the decomposition of nitrite in the very same sample solutions.
(3) The decomposition of nitrite was promoted by the addition of sorbic acid, potassium sorbate and sodium sorbate even in the absence of ascorbate.
In the presence of ascorbate, however, sorbic acid promoted the decomposition of nitrite, while potassium sorbate and sodium sorbate inhibited appreciably the decomposition of nitrite.
AF 2 exhibited no effect on the behavior of nitrite.

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The ' Protein Score ' (FAO 1955) is computed from the amount of the first limiting amino acid contained in 1gN or 6.25 protein and the quantity of the corresponding amino acid in the same amount of the reference protein.
When the amount of protein, which is being examined, is increased to more than 100guntil its first limiting amino acid is equal to the quantity of the corresponding amino acid in 100g reference protein, the cholesterol content in the same amount of the residue protein in mg, is provisionally referred to as ' Cholesterol Protein Score Index ' (C. P. S. I.).
In the present report the amino acids of the defatted residue of Japanese food, of animal origin, were determined by means of amino acid auto analyzer (KLA-3A), and the protein score was computed in each case. The cholesterol protein score index was obtained through dividing the cholesterol crude protein index by the protein score in each food.

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