In order to obtain fundamental information on the desirable methods of cooking for preventing atherosclerosis and directing therapeutic purpose, changes in contents of moisture, crude fat and cholesterol and in the composition of fatty acids before and after cooking were examined using minced beef (round), pork (ham) and fish (cuts, Red sea bream) and the mixture of Promic TB-6 with these meats (1: 1, w/w). The following results were obtained.
Cooking without oil: In grilling and roasting some decrease in the amounts of crude fat and cholesterol was observed.
Cooking with oil: In the methods which might cause the decrease in the content of moisture and the considerable transfer of cooking oil such as deep fat frying and broiling (meats had been oiled for 6 hours prior to cooking), there were decreases in cholesterol contents and in the proportion of saturated fatty acids, while percentage of polyunsaturated fatty acids was increased.
An introduction of cutting method by which cooking oils contact well with meats (such as mincing), on supplementary use of the materials having a powerful oil retaining potency (such as plant proteins) were expected to bring transfer of vegetable oils. These tendencies were marked in the sequence of fish, beef and pork. Safflower oil appeared to behave more preferably than sunflower oil.

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The extent of transfer of vegetable oils during cooking to minced beef, pork and fish was measured using ³H labeled sunflower and safflower oils. Also, the composition of the oils transferred to beef was examined.
The amounts of oils transferred were influenced by differences in tissue structure, moisture and crude fat contents materials and the viscosity of oils of the meats fish showed the most significant transfer of oil. In addition, oiling before heating appeared to be effective for transfer of oils to the meats, especially when the materials was mixed with plant protein such as Promic TB-6.
There was some quantitative differences in the rates of transfer of individual fatty acids between sautéing and deep fat frying or broiling. In general, saturated fatty acids were to some extent preferentially transferred, indicating a difference in the rate of transfer of cooking oils due to the degree of unsaturation.

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In order to study the oxidative deterioration of fats contained in dried foods, model systems consisted of soybean oil or methyl linoleate with casein were incubated under three different humidities, that is, relative humidity (RH) 0% (low), 48% (middle), and 83% (high). Kori-tofu was also incubated in the similar manner.
The changes in lipids and proteins were examined.
1) Incubating soybean oil with various supporting materials, such as, proteins, amino acids, starch, synthetic polymers, etc., at 50°C, the oxidation of soybean oil was depressed when proteins were used as supporting materials.
2) When methyl linoleate (ML) adsorbed on casein was incubated at 37°C, the oxidation of ML was markedly depressed. Formation of polymers occured when they were incubated at 50°C under high RH.
3) When Kori-tofu was incubated under high RH, recovery of extractable lipids was lowered, and polymers were formed accompanied by the loss of linoleic acid, linolenic acid and tocopherols.
4) On the other hand, the residues of ethyl ether extracts of ML-casein and Kori-tofu incubated under high RH showed the decrease in digestibility and the loss of amino acids.
5) The damage of lipids and proteins were considerably suppressed by incubating under middle RH.

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The chemical modifications of wheat gluten were investigated for preparing the product having the desirable properties for food processing.
Both emulsion stability and solubility were markedly improved by the deamidation and acylation (acetylation, succinylation) of gluten. pH showed the similar effects on emulsifying properties and solubility of deamidated gluten and acylated gluten.
Emulsion stability was not affected by the heating of the protein solution, but decreased by the addition of sodium chloride.
It was shown that the use of these modified glutens into fish sausage caused similar changes to the emulsion stability data.
These results suggest that these modified gluten would be useful as emulsifying agents in food processing.

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Isolated liver cells from adult rats were cultured for 24 hours in enriched medium (Williams medium E, WE) with 10% fetal bovine serum, and with or without various hormones and then the amino acid concentrations in the medium were measured. The concentrations of alanine, glycine, arginine and aspartate decreased very much, the decreases in alanine and glycine being markedly enhanced by the presence of glucagon. The concentrations of lysine, tyrosine, phenylalanine, threonine and methionine decreased moderately and dexamethasone stimulated that of tyrosine, particularly.
On the other hand, the concentrations of isoleucine, leucine, proline, cystine, glutamate and histidine did not change significantly and those of serine, valine and ornithine increased.
These results can mainly be explained by the metabolic activities of liver cells, particularly gluco-neogenesis for alanine and aspartate, ureogenesis for arginine and ornithine, and interconversion of serine and glycine and the inability of hepatocytes to metabolize branched chain amino acids. These explanations were supported more clearly by results using unsupplemented salt solution (Hanks' solution). In this medium the concentrations of amino acids released into the medium were very similar to those found in liver proteins, except for those of alanine, glutamate, aspartate, proline and arginine, which were much lower than in liver proteins.
The present work also suggests that liver cells in primary culture retain various liver functions and thus are useful for studies on liver functions in vitro.

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Potassium is sufficiently contained in the body and easily taken from diets every day. But hypokalemia in man is often seen unexpectedly in patients, being suffered from starvation, repeating vomitting and diarrhea, being treated by diuretic, and so on. So, rats were experimented to make a potassium-depletion disease with potassium deficient diets.
The results were as follows:
1. In young male rats, appetite and weight gain started to decrease just after the initiation of the experimental feeding, and diet efficiency after feeding of 1 week decreased by 30% comparing with control rats.
2. Rats fed potassium deficient diet behaved too keen and too sensitive and tiptoed from about 4 weeks and the abdominal muscle became soft after about 3 weeks and thenceafter hard.
3. By biochemical examination of blood, SGOT increased and potassium value decreased from about 2 weeks but other data were in the normal range.
4. Atrophy of the thymus and hypertrophy of the kidney were marked after about 2 weeks.
5. By being kept on potassium deficient diet for 3 weeks, fatty liver was generally found and the extent of fatty infiltration became more pronounced after 5 weeks.
6. In X ray examination, no abnormality was found in all skeletons of rats after about 5 weeks.

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The rats in which an extensive fat accumulation had occurred by feeding the diets consisting of the wheat-, rice and miyazaki-pattern amino acid mixture at low levels were further given 20% casein diet for 4 weeks. The recovery from the fatty liver in these rats was investigated through the determinations of serum triacylglycerol and liver lipids.
The body weight gain of all the experimental rats markedly increased during recovery period as compared with those during the low amino acid diets feeding period. In recovery process, however, there was no difference in the feed efficiency (body weight gain/food intake) among all the experimental groups. The contents of serum triacylglycerol of the experimental rats increased by feeding 20% casein diet and recovered nearly to the normal level. For the hepatic triacylglycerol, all the experimental groups showed intensive decreases compared with those in the rats on the low amino acid diets, and in the miyazaki-pattern diet group, contents of all the hepatic lipid components were less than those of two other experimental groups. The conjugated lipids of the rice-pattern diet group had a tendency to be higher than the wheat-pattern diet group. The amounts of vacuoles in the liver cells of the histological sections decreased and the histochemical findings of hepatic parenchymal cells recovered to the normal. Whereas a few hepatic cell containing Sudan III-positive granules was still found. However fibrosis was not observed. It was indicated from above results that feeding of the casein diet (20% level) to the rats in which an extensive fat accumulation had resulted from the low amino acid diets would be effective for the recovery from a fatty liver.

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As a fundamental study on the efficient utilization of marine fish resources as foodstuffs, the white muscles of nine species of newly exploited fish were analyzed for proximate composition, non-protein nitrogenous constituents and amino acid composition of proteins. The results obtained are summarized as follows.
1) The content of crude fat in pelagic armorhead Pentaceros richardsoni was noticeably high, amounting to 16.3%.
2) The muscle extracts of barracouta Thyrsites atun, silver warehou Seriolella maculata and warehou S. brama were characterized by the presence of large amount of free histidine, and those of southern blue whiting Micromesistius australis and New Zealand whiptail Macruronus novaezelandidae by the presence of large amount of anserine and small amount of 1-methylhistidine. The muscles of pelagic armorhead and southern blue whiting were found to contain more than 100mg of taurine/100g of the muscle.
3) Among nucleotides and related compounds, IMP was dominant in all the fish analyzed, and its content exceeded 200mg/100g of the muscle in barracouta, silver warehou and warehou.
4) Trimethylamine oxide and creatine constituted important parts of nitrogenous extractives in the muscles of these fish. Especially, the content of trimethylamine oxide in look-down dory Cyttus traversi, kingklip Genypterus blacodes and New Zealand hake Merluccius australis, and that of creatine in barracouta, silver warehou and warehou were very high.
5) The amino acid compositions of muscle proteins of these fish closely resembled each other, and the levels of amino acids were mostly within the range of the values reported on the common edible fish in Japan. These results suggest that the muscles of the analyzed fish are excellent protein sources as those of the common fish.

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Fasted rats (F₁) were refed (R₁) with a high fat (olive or corn oil) and high protein diet, a high fat and protein free diet or a fat free and high protein diet, then fasted again (F₂) and refed (R₂) with a fat free diet. The periods of fasting and refeeding were 2 days. The inductions of glucose-6-phosphate dehydrogenase and malic enzyme in R₂ were significantly lower in the rats fed the high fat and high protein diet previously (R₁) than in the others, and lower in corn oil-fed rats than in olive oil-fed rats. The inductions in those rats fed the protein free diet in R₁ was very high and not different between corn- and olive-oil fed groups. The similar effects were observed in these rats treated with 8-azaguanine during R₁. It is suggested that the high fat diet containing protein, induces “repressor-like” system to code synthesis of glucose-6-phosphate dehydrogenase and malic enzyme in rat liver. Corn oil seems to induce “repressor-like” system more actively than olive oil. The similar results were observed in acetyl-CoA carboxylase, but the enzyme activity in R₂ was not significantly different by fat.

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The influence of the aging on the absorption of the soybean oil and lard was investigated by using rats 1, 4, 10, 14, 18, month rat respectively. Provided that experiment diet contained the soybean oil and lard of 10%. The results obtained were as follows;
(1) The absorption of soybean oil and lard gradually decreased with the aging, and the absorption of soybean oil was higher than that of lard.
(2) The excretion of neutral sterol was almost constant in the both case of soybean oil and lard, but the excretion of bile acid increased with the aging.
(3) When the excretion of bile acid increased, the absorption of fat and oil was apt to decrease.
(4) The fatty acid composition of lipids in feces were difference between soybean oil and lard, that is, saturated fatty acids in the feeds were 34-64% (soybean oil) and 60-73% (lard) respectively.

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Recently, the production of commercial frozen-stored foods has been increased. However, no investigation has been reported on the lipoper-oxide included in frozen-stored foods in the market.
The level of lipoperoxide on 58 kinds of commercial foods was investigated: commercial frozen-stored foods (29 kinds), canned provisions (17 kinds) and dried fishes (12 kinds).
The results obtained are shown in Table 1-3. In Table 1, the level of lipoperoxide was found to be increased as their storage time increases. The level of lipoperoxide of dried fishes were higher than those of the other samples.

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