In Ryukyuan cookery there are many ways of cooking, depending on the various parts of pork used. However, the primary process involves boiling the pork for several hours and then adding seasonings. The change of the chemical components of the pork, especially the lipid components, at various times during the cooking in order to determine the effect of heat processing, were examined. The results obtained as follows:
1. The waste ratio of each part of the pork was determined: i, e. the highest,54%, was in boiled pig foot with bone and 49% in raw one and the next was 34% and 23% in lungs and kidney respectively.
2. The greatest difference in weight change by heat processing was in the muscle tissue with less change occurring in other parts of pork, such as the pork skin and connective tissue.
3. For all parts of the pork, the value of general components was less in the cooked pork than in the raw pork; however, the percentage of protein increased in the boiled pork, while the lipid contents decreased in the spare ribs with bone, the stomach, and the intestines.
4. The highest amount of cholesterol was in the spleen.
5. There was a correlation between lipid content and cholesterol content after heat processing, with the positive p value being less than 0.01 (p 0.01).
6. The lipid content in uncured sidemeat with skin decreased 4% with 30 minutes boiling and 15% with 4 hours boiling. The longer the period of heating with seasonings was, the greater the decrease in lipid content was.
7. It was found that the lipid content in the pork of Ryukyuan cookery was greatly decresed by heating for several hours.

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We discussed about preservative properties of Tsuto-Dofu, the local dish in Aizu. Tsuto-Dofu was preserved at 5± 5°C in electric refrigerator. The quality of Tsuto-Dofu was evaluated by sensory test and instrumental analysis.
The results obtained were as follows:
1. The deterioration of Tsuto-Dofu was recognized by sensory test at the fourth day in the preservation.
2. The color of Tsuto-Dofu became yellowish in the preservastion but this phenomenon didn't have influence on the quality judged by the sensory test.
3. Significant difference of texture was recognized by the sensory test at fourth day but there is no significant difference in the hardness determined by curd-meter. Seemingly this came from that sensory evaluation of texture involved not hardness but the other factors.
4. The absorbance of water, in which Tsuto-Dofu was soaked for the preservation, increased with the lapse of time, while the pH decreased on the contrary. From these results, it seems that the values of absorbance and pH are usefull as indices of deterioration.

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The measurement of softening of tangles was carried out by heating model cooking solutions which contain various condiments. The Laminaria japonica Areschoug produced in Hokkaido was used as sample material. The cooking solutions were kept at 90°C for 60 minutes each of which contains organic acid (0.5,1%), amino acid (0.5,1%), sugar (5,10%) and NaCl (2.5,5%), respectively. Other solutions included two, three or four condiments described in the above. Thereafter, the softness of the materials was measured. The results revealed that softening of the materials by the sugar or amino acid solution was restrained comparing with the control, while softning was remarkably enhanced by the other single-condiment solutions. Softening was always remarkable by enhanced cooking solutions which contain two or three condiments, in which the organic acids were effective when combined with one or two condiments. NaCl was most effective to soften the materials quickly when combined with the other three condiments.

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The morphological observations of the tangles which were heated in model cooking solutions were carried out by means of light and electron microscopes. The sample materials was Laminaria japonica Areschoug produced in Hokkaido as in the previous report. The result revealed that the reticular structure of the cell wall was fine when the materials were heated in the cooking solution which contained such a condiment as sugar, while the structure of the cell wall was rough and swollen up to two-three times compared with the control when tangles were heated in the cooking solutions which contained organic acid, NaCl or two-four condiments.

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Meat with different fat content and form was fried at 180°C for 2.5 minutes with corn oil, and the amount of meat fat migrated to the frying oil and the amount of the oil adsorbed on the fried meat were determined by gas chromatography.
The results obtained were as follows:
1. Meat with different fat content: It was confirmed that the more the content of fat in the raw meat was the more the amount of defatting increased. The difference of the amount of oil adsorbed in fried meat was not observed between the low fat meat and the medium fat meat. The amount of oil adsorbed was larger in the fatty minched meat than in other minched meats, caused by remarkable defatting.
2. Meat with different form: Amount of oil adsorbed in the minched meat was significantly larger than that in the meat squarely cut, but difference in amount of defatting was not observed between the minched meat and the meat squarely cut.

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Muffins and breads were prepared by using sago starch and the cooking properties thereof were examined by instrumental measurements and each product was organoleptically evaluated. The results are summerized as follows:
(1) When muffins were prepared by adding 10% of vital gluten to various starches, an organoleptic evaluation indicated that the sago starch muffin thus obtained had an excellent palatability, a high elasticity and a uniform texture.
(2) Breads were prepared by adding 30% various starches to highly viscoelastic wheat flour and further adding 10% of vital gluten thereto. The one prepared with sago starch showed an excellent puffing, a high elasticity and a desirable crumblingness, compared with a control bread or those prepared with other starches.
(3) Breads were prepared by adding 36% of vital gluten to various starches. The one prepared with the use of sago starch showed a high cohesiveness, elasticity and softness, compared with a control bread. Further, an organoleptic evaluation indicated that the former bread was a better puffing than the control and was more preferable to those prepared with corn starch or potato starch in appearance, elasticity, softeness and total evaluation. Thus it was revealed that sago starch was usable for puffed foods such as muffins and breads and gave a product having a uniform texture and an excellent puffing.

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The change in the degree of gelatinization, moisture constent and creep measurement of starch breads by storage were determined. The results obtained were as follows:
(1) A sago starch bread showed the highest degree of gelatinization i. e.,90%, immediately after baking, while a potato starch and corn starch breads showed 86% and 69%, respectively. The degree of gelatinization of the sago starch bread after freezing was next to that of a control one. It meant that the former was hardly denatured by freezing.
(2) The sago starch bread showed little change in the viscoelasticity when stored at room temperature and frozen. The physicochemical values thereof were approximate to those of the control one.
(3) The degree of gelatinization and viscoelasticity of the sago starch bread well agreed with the organoleptic evaluation of that by order-method. It meant the bread was soft and elastic.
(4) Three physicochemical values, i, e., the degree of gelatinization, the moisture content and the static viscoelasticity showed a high positive correlation to each other.

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The influences of exchanging water during cooking called "shibukiri" treatment on the flavor of cooked adzuki beans were investigated.
Cooked odor concentrates were obtained from adzuki beans with or without “shibukiri” treatment by simultaneous distillation and extraction. The odor concentrates were analyzed by GLC and GC-MS to identify each volatile components.
Total 38 compounds were identified or tentatively identified among which 3-methylbutanal and n-hexanal were newly identified. These aldehydes possessed beany and unpleasant odor, and were considered to vaporize or decompose by 2hr cooking.
Cooked odor concentrates obtained from adzuki beans without “shibukiri” treatment possessed sweeter aroma like cooked adzuki beans than those from “shibukiri” treated ones, because the former contained 3-hydroxy-2-butanone, maltol, furans and phenol compounds which were considered to contribute to the characteristic sweet aroma of cooked adzuki beans. These compounds were formed by heating the water extract of adzuki beans before “shibukiri” treatment.
The results of sensory test also showed that cooked adzuki beans without “shibukiri” treatment possessed sweeter aroma like cooked adzuki beans.

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Foaming tendency of frying oil during egg-frying and of heating oil with soya lecithin or egg yolk lecithin were investigated. The method was to determine the foam height for a series bubbling when a potato slice (5 mm in diameter × 5 mm in thickness) was thrown into bottomless test tube in the frying oils. During egg-frying, phospholipids of the egg migrated to the frying oil. As the results an increase of foaming tendency of the oils were observed. The higher the migration of phospholipids was, the higher the foaming tendency of the oil was. Added soya lecithin or egg yolk lecithin promoted the foaming tendency of oil during heating, but the addition of choline and phosphoric acid (a component of phospholipids) showed no effectiveness. Hydrogenated Soya lecithin (100%) showed larger foaming tendency of oil than unhydrogenated soya lecithin. Oxidation stability and residual percentage of tocopherol after egg-frying was higher in the oil with egg-frying than in the heating oil without egg-frying.

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The study was performed in order to clarify the actual condition of the taste preference, marketing and bacterial contamination in commercial noodles.
The results were as follows:
1. The taste preference was examined for 166 female students. They were not fond of Japanese soba but of Japanese udon noodles, Chinese noodles and Spaghetti.
2. The name of the manufacture and the date of production were recognized in 47 brands of boiled noodles, but only 27.7% of the sample indicated edible period.
3. The number of viable cells in boiled udon noodles and boiled soba noodles were 3.0×10²/g>∼5.2×10⁶/g and 3.0×10²/g>∼1.4×10⁸/g, respectively. Coliform organisms were detected in 17.5% of boiled udon noodles and in 26.1% of boiled soba noodles. Detection ratios of Staphylococcus aureus and Bacillus cereus were 0% and 13.8%, respectively.

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We investigated the devices for removal of chloroform formed in vegetables treated with NaClO and the changes in contents of vitamin B₁, B₂ and C.
Washing five times with distilled water could remove almost chloroform of vegetables sterilized with NaClO and storage of the vegetables at 4°C in a refrigerator also showed the same effect.
Vitamin B₁, B₂ and C in cabbage were destroyed by about 50% by the treatment with NaClO but those in garland chrysanthemum were not destroyed, These resutls might be due to destrucof cells of cabbage by cutting with a knife and then easy contact of NaClO to the vitamins in cells. But it was not the case in garland chrysanthemum.
It is concluded that washing vegetables with water is necessary when NaClO is used for the sterilization.

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