The objective of this work was to develop a practical method for monitoring the quality of oils during the frying process. Experiments were carried out on foaming of frying oils. In a previous paper, we compared the length of foam extension with the extent of deterioration of soybean frying oil, and it was observed that the foam was more extended according to deterioration. The rats fed oils with different degrees of foam extension showed growth depression with more than 32 mm of foam extension. Thirty-two of foam extension also corresponded to 21 mm of foam height. To know the relationship between kinds of oil and foam height during heating, oils (soybean, corn, olive and coconut oils) were heated at 180°C in fryer, and the changes of foam height, carbonyl and anisidine values, and/or oxidized fatty acids (fatty substances insoluble in petroleum ether) and tocopherol (Toc) contents were determined.
Higher foaming was observed in the case of coconut and olive oils and forming in soybean and corn oils was low. Carbonyl value, contents of oxidized fatty acids and thermal decomposition rate of Toc in oil by heating were higher for olive and cocount oils than for soybean and corn oils. The results suggest that high correlation exists among foam height, increase in carbonyl value, contents of oxidized fatty acids and the decrease of Toc in oils. Deterioration grade of frying oils collected from home and school refectory was low according to the measurement of foam height.

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The contents and cooking methods of many kinds of dishes in various places of the world may be recorded by standardized and unified terms.
By means of substituting the special cookery signs for such terms and arranging these sings according to definitive rules, it is possible to describe the contents and cookery methods of all sorts of dishes as the chain of these special cookery signs.
For instance, YAKIIMO (broiled sweet potatoes), one of the most simple and typical Japanese cooking methods can be recorded as 2M=1: SWEET POTATO (PO),120g,1/1,2: W 1. S9(-),3: I12,6: H 46,180°C,20 min,9: Y12
In the near future, if such a standardized cookery signs method as this is improved and adopted for the purpose of recording and describing worldwide varieties of human dishes, it will be very useful and beneficial for every nation to understand food and nutritional culture.
Besides, in the recent computerization of office work and life, this cookery signs method should have significant benefit for cooking recipe indication, deta base setting and other terminological purposes in various practical fields.

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A study on preserving conditions of cream puff paste was conducted on the relation between preserving temperatures (35°C,20°C,5°C, -20°C) or periods and the shape, volume and hollow-forming of cream puff crust.
The results obtained were as follows:
1) The paste prepared should be baked immediately, because the temperature of paste rose in short time and the volume of crust was large.
2) The preserving periods were 3 hours at 35°C and 24 hours at 20°C. Longer preserving periods brought decreasing of swelling. It was found that the transformation of egg-constituents and emulsification of ingredients prevented the swelling under high temperatures.
3) At 5°C, the paste was preserved for a week with keeping large volume. This means that the influence of retrogradation of starch on swelling was negligible.
4) When kept for 2 months at -20°C, hollow body was formed. But the shape of crust was impaired. Accordingly it was considered that the paste was damaged in frozen storage.

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The palatability and rheological properties of rice cooked in water and in Hon-Mirin solution was compared. The concentration of Hon-Mirin, used was 1.7%.
Sensory evaluation showed that rice cooked in Hon-Mirin solution was more favourable than rice cooked in water on the appearance, stickiness, hardness, umami and total acceptance.
Force-time curves of rices cooked in these conditions were examined under compression at a constant speed. When cooked in Hon-Mirin solution, initial elasticity and total and adhesive energies of the rice were greater than those of rice cooked in water.
It was found that rice cooked in Hon-Mirin solution had higher falling speed in water than that of rice cooked in water. Supposedly the smooth surface of the former rice caused increase of falling speed. There were no differences on the moisture and the specific gravity between two cooked rices.

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The contents of the eight inorganic elements (Na, K, Ca, Mg, Cu, Mn, Fe and Zn) in vegetables were determined by atomic absorption and flame emission spectrometry after several cooking (boiling for 2,5and 10 min, and heating with micro-wave oven), and the percent of the elements remained in the tissues after the cooking was estimated. The samples used in this study were five root vegetables such as Japanese radish, turnip, carrot, east Indian lotus (root) and edible burdock.
1. The remaining amounts of Mg, Ca, Cu, Mn, Fe and Zn in the vegetables after boiling in water were higher than those of Na and K.
2. The remaining percent of Na and K after boiling for 2,5 and 10 min were 60,50 and 40%, respectively, whereas those of other 6 elements after boiling for 2,5 and 10 min were 80,80,70%, respectively.
3. The remaining percent of elements in the tissues after cooking with micro-wave oven was higher than that in the tissues cooked in boiling water.
All the elements except Ca in Japanese radish and edible burdock were remained 80-90% in the tissue after cooking with micro-wave oven. The remaining percent of the immersed tissue (MW I) in the cold water after cooking with micro-wave oven were significantly lower (86±4%) than that of tissue without immersing (94±4%).
4. The contents of Na and K in Japanese radish after cooking in boiling water for 10 min were one-third and one-fourth of the contents of raw materials, respectively. The remaining percent of Ca in turnip, carrot and east Indian lotus (root) was relatively high. In the edible burdock the remaining percent of Na, K and Ca were low, whereas that of Mg was high. Remaining percent of Ca and Fe in the edible burdock after cooking in boiling water were similar to those cooked with micro-wave oven, and the average of the remaining percent of Ca and Fe was 57±4% and 96±2%, respectively.

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During the course of investigating the thermal stability of chlorophylls in foods the different stability of chlorophyll a and chlorophyll b was examined in detail.
The following results were obtained.
1) When the freeze-dried powed of spinach was kept at 100°C or 120°C, chlorophyll a was more stable than chlorophyll b.
2) When the thin-film from the solvent extract of spinach was kept in dark or in light at 65°C,75°Cor 85°C, chlorophyll b was more stable than chlorophyll a.
3) When 80% acetone extract of spinach, chingentsuai or pimento was stored at the room temperature, chlorophyll b was more stable than chlorophyll a.
4) In 80% acetone extract chlorophyll a was more stable than chlorophyll b in the presence of βcyclodextrin or L-ascorbic acid. However, chlorophyll b was more stable than chlorophyll a in the presence of magnesium lactate. Also chlorophyll b was more stable than chlorophyll a in the presence of β-carotene, retinyl acetate or α-tocopherol.
5) When freeze-dried powder of spinach was stored in agar, chlorophyll b was more stable than chlorophyll a in the presence of riboflavin or cholic acid. However, chlorophyll a was more stable than chlorophyll b in the presence of L-ascorbic acid, β-carotene, retinyl acetate or α-tocopherol.

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Effects of the ratios of vinegar, sugar and salt in seasoning of preference of sushi-meshi (cooked rice for sushi) were studied. Scheffé's simplex lattice design for three component systems was used for experimental method as model systems. Sensory evaluations for sourness, sweetness, saltiness, texture and total acceptance were determined. Rheometer was used for the measurments of texture parameters. Sushi on the market was also studied to compare with those model samples. The results were as follows:
The quadratic equations were obtained using the respective parameters and sensory scores for each of model systems relating ingredient ratio to preference, and the characteristics of these models were shown by the estimated curves.
Desirable ratios in the seasoning were 11.4-14.0%,5.9-7.0% and 1.2-1.7%, for vinegar, sugar and salt, respectively. It was found that the texture was an important property on sushi-meshi by multiple regression analysis of sensory evaluations and it was different from ordinary rice.
Ingredient ratios for sushi-meshi on the market used in this experiment were 13.9-18.5%,9.2-13.7% and 2.2-2.4%, for vinegar, sugar and salt, respectively, and these were higher than those for model samples.

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Chlorophyll in persimmon leaves is rapidly decomposed into pheophytin by heating, causing the green color to disappear. In this work we studied the behavior of acid and tannin in persimmon leaves during heating, which is known to affect chlorophyll, and methods to prevent discoloration of persimmon leaves during heating.
The results obtained were as follows:
1) The acid and tainnin content of persimmon and maple leaves, whose chlorophyll was rapidly decomposed by heating, was higher than that of vegetable leaves whose chlorophyll is relatively resistant to heating.
2) Although acids and tannins in persimmon leaves were eluted during heating, their concentrations were still high at the early stage of heating when chlorophyll decomposition had proceeded. These results suggest that the contact of chlorophyll with acid and tannin, brought about by the rapid transformation through heating of the cellular membranes which separate the chlorophyll from the other two materials in untreated leaves, causes the rapid deterioration of chlorophyll in persimmon leaves.
3) When lyophilized persimmon leaves were dipped into water, acid and tannin were largely removed from the leaves. The chlorophyll of persimmon leaves after this treatment was remarkably resistant to heating. Furthermore, the green color of persimmon leaves dipped in a sodium hydrogencarbonate solution before heating was more resistant to heating.

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[in Japanese]

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