The fact is well known that the liquid whole egg, when irradiated with microwave, swells and then shrinks, changing its physical properties into those of elastic gumlike material. In order to elucidate the phenomenon of gum-formation, we examined the changes in the components and composition of the samples heated by two typical methods, microwave-irradiated sample and conductively heated one.
Results on microwave-irradiated sample are as follows :
1) Its surface was microscopically observed to be folded like waves.
2) The rate of extraction and digestion determined with both egg protein and egg yolk lipid was not so law as expected from its compact texture.
3) The rate of deuterium-proton exchange was higher than that of conductively heated sample, so the peptide chain of gummed egg protein seems to be very flexible.
4) It might be considered that the coexistence of air layer and lipid layer contributes to make the gumlike texture more elastic

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The changes of physico-chemical properties of whole egg and egg albumin during microwave heating were studied. The change of the water content of several samples different in initial water content was determined during and after the heating. And on egg albumin the relationship between the change of water states and the phenomena of inflation and of gumming was investigated. Results are as follows :
1) Whole egg and egg albumin, the initial water contents of which were ranged in 40-50 %, were the most subject to inflation, but they became gum-like at the higher water content more than 50 %.
2) Water holding capacity and content of the bound water were increased at the point of inflation.
3) The velocities of temperature-rise and of water evaporation were especially high near the inflation point, and the relationship between velocity of temperature-rise and water content in microwave heated samples was very different from that in the conductively heated ones.

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The effect of powdered starch syrup and sucrose compound on jelly was investigated. It was found that the most desirable sweetness of jelly was brought about by the mixture of 12w/v % sucrose. Agar and carrageenan jellies with the same sweetness were prepared by replacing the amount of sucrose of 0 (No.1), 1/3 (No.2), 2/3 (No.3) and 1 (No.4) with powdered starch syrup, respectively. The measurement was made on syneresis, texture parameter, rupture parameter, transparency and preference parameter of jelly at 20°C. Syneresis, hardness, adhesiveness, rupture stress and rupture energy increased by adding up powdered starch syrup. As the result of sensory evaluation, it became clear that the jelly with 60 w/v % powdered starch syrup compound (No. 4) was the most undesirable, while the significant difference on preference parameters was not recognized among the other three jellies (Nos. 1-3). From the point of delicious medical diet of high energy, it can be concluded that the best jelly is to be prepared by the compound of 40 w/v % powdered starch syrup and 4 w/v % sucrose (No.3).

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Cooked broad beans are called “Otafukumame” which have been eaten their cotyledons and seed coats together, and are blackened during cooking with NaHCO₃. As the effect of NaHCO₃ was thought to be not only to blacken, but also to soften beans, then the water absorption and the hardness of beans during soaking and cooking were determined. Moreover, histological changes during soaking and cooking were investigated.
Results were summarized as follows :
1) The addition of NaHCO₃ was effective to make beans more soft and better appearance in color.
2) From optical microscopic and scanning electron microscopic observations, it was shown that the cotyledon could easily separate from the seed coat by the cooking in NaHCO₃ solution (0.3-2.0%) and the palisade cells became separable each other and were somewhat collapsed.
3) To obtain the palatable “Otafukumame, ” the best cooking procedure was found to be as follows : soaking the dried beans in 0.3-1.0 % NaHCO₃ solution, cooking in 0.3 % NaHCO₃ solution after washing with water.

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Some fruits and vegetables become soft followed by ripening as tomato and persimmon, but others do not exactly change their textures as apple and pear. In this study the relationship between the textures and activities of pectin-hydrolysing enzymes was examined in various fruits and vegetables.
Texture was measured with a rheolometer, and both activities of pectinesterase and polygalacturonase were determined as pectin-hydrolysing enzymes.
1) Fruits and vegetables having high pectinesterase activities are as follows : persimmon (“Fuyu”), banana, peach, fig, tomato, kiwifruit, melon and strawberry. Whereas apple and pear have the low activities.
2) Change of texture and pectinesterase activity was measured during the ripening stage of persimmon and strawberry. It was found in both fruits that texture was gradually reduced while pectinesterase and the content of reducing sugar increased during the ripening stage.

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We are available to make use of worn-out Kimono repeatedly by unsewing, mending and reforming, because Kimono is easily reconstructed to original form due to its planary construction as compared with solid construction of Western clothes.
The aim of this paper is to clarify the durability of Kimono fabrics by observing and analyzing the damaged spots of worn-out Kimono macrographically and comparing them with the broken spots produced mechanically by Universal wear tester and Mullen bursting tester. The main results are as follows :
1) The damaged spots in Kimono worn-out 8-70 years long concentrated locally at knee parts. It was observed that the warp years were more broken down than the weft yarns at the damaged spots, because the tensile stress was applied on the warp yarns repeatedly at every sitting straight on Tatami mat.
2) On the fabric abraded multidirectionally by Universal wear tester, the warp and weft yarns of the near by equal number were broken.
3) The correlation coefficient between the abrasion rates of worn-out Kimono and of fabrics abraded by Universal wear tester was significant at 1 % level.

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The studies were successively carried out on the physical and chemical properties, formaldehyde contents and resistances to ultraviolet irradiation of cotton and viscose rayon fabrics finished with diammonium hydrogen phosphate, boric acid and borax as flame retardants, singly or as mixtures of these two or three, combined with a resin of glyoxal type by the single bath method and double step method in which the resin finish was followed by the flame retardant finish.
The following results were obtained.
1) Considerable reduction in tensile strength of cotton fabric as well as in breaking elongation of both cotton and viscose rayon fabrics was observed when diammonium hydrogen phosphate was used as a flame retardant in combination with resin finish.
2) Boric acid and borax showed a remarkable resistance to harmful effect of ultraviolet irradiation on tensile strength, elongation and flame retardancy, while diammonium hydrogen phosphate showed a significantly enhanced reduction of these physical properties when exposed to ultraviolet irradiation. The determination of nitrogen evidenced that such reduction was attributable to liberation of ammonia from the phosphate caused by ultraviolet irradiation.
3) Unfavorable behaviors by diammonium hydrogen phosphate were improved by addition of boric acid and borax.

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