The effect of thermal oxidation and hydrolytic promoters of oil or their inhibitors were investigated on the deterioration of oil and decomposition of tocopherol (Toc) in oil with or without an aluminum cover float. Vegetable oils (soybean, hardened soybean, rapeseed and olive oils) under the presence of oxidation promoters of oil (ferric and cupric stearates), hydrolytic promoters of oil (stearic and citric acids, or magnesium oxide) and their inhibitors were heated in glass tubes (2.7×20cm) at 180°C.
The deterioration of oil and decomposition of Toc in oil were apparently promoted by addition of ferric and cupric stearates. On the other hand, the added silicone oil, tert-butylhydroquinone (TBHQ) and ascorbyl palmitate (As. P) showed preventive effects on the deterioration of oil and decomposition of Toc in oil. And moreover, the deterioration of oil and decomposition of Toc in oil containing As. P heated with the aluminum cover float were clearly less than those without the float.

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Thermal decomposition of added antioxidants in oil and methyl esters of fatty acid were investigated. Oils (soybean and olive oils) and methyl esters of fatty acid (oleate and linoleate) with or without antioxidants (butylated hydroxyanisole [BHA 3-isomer], tert-butylhydroquinone [TBHQ], eugenol, sesamol, quercetin, oryzanol, β-carotene and flavone) were heated in glass tubes(2.7×20cm)at 180°C. The remaining amounts of BHA, eugenol, sesamol and TBHQ in the oils and methyl esters of fatty acid were determined by HPLC. And the remaining amounts of oryzanol, quercetin, β-carotene and flovone were determined by UV absorption spectrometry.
The degree of thermal decomposition of antioxidants in methyl esters of fatty acid was observed to be much higher in oleate than in linoleate. Thermal stability of antioxidants in oil were in the order of oryzanol>quercetin>eugenol>sesamol>BHA, but β-carotene and flavone were most unstable for heating. Anisidine and carbonyl values of oil heated with TBHQ and oryzanol were markedly low. On the other hand, β-carotene and flavone accelerated thermal oxidation of oil.

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Apparent diffusion coefficients of sodium chloride in fish meats, Dapp' were estimated from the amount of the salt absorbed when the salt was sprinkled on the outer skin or inner meat side of fish filets. A fish filet was assumed to be a plate with an infinite depth. The Dapp values were in a relatively narrow range of 10^-7 to 10^-6 cm²/s when the salt was sprinkled on the inner meat side of filet. On the other hand, when the salt was sprinkled on the skin side of filet, the Dapp values were in a range of 10^-9 to^-6 cm²/s and were greatly dependent of both the kind and the individual of fish. In the latter case, there seemed to be three diffusional resistances in series, that is, the skin, subcutaneous fat, and meat layers. Regarding the skin and subcutaneous fat layers as a layer, the diffusion coefficient of the salt in the layer, Ds' was evaluated under some assumptions. The Ds values were very small, and between 10^-10 and 10^-8 cm²/s.
A correlation between water and fat contents was also made using the contents of fifty-five samples. The logarithmic value of fat content was empirically expressed by the quadratic equation of water content.

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We prepared cake batter for sponge and pound cakes with both 120 and 190 gram in weight in 12cm round cake pans. Cakes were baked under six different baking temperatures from 150°C to 200°C with 10°C intervals.
We examined how the temperature shifted inside these cakes during baking under pre-set baking temperature and also the effect of temperature changes on the final shape of the product, as a cake rose while baking.
We conclude from the results of our experiments as follows:
1) In all cases, the higher the baking temperatures were, the faster the inner temperature of cakes rose.
2) The sponge cake of 120g had the fastest rising speed of inner temperature. The sponge cake of 190g had the second faster speed and the pound cake of 190g had the slowest one.
3) It became clear that there were three stages in the changing pattern of the temperature. The first stage was until the temperature at the point of 1cm from both edge and bottom of the cake, became stable. The second stage was until the core temperature stabilised. The third stage was up to the completion of baking. A sponge cake rose mainly in the first stage (93-103% of the final height), barely did so in the second stage and became flat on the top. A pound cake rose to 77-84% of the final height in the first stage and kept on rising also in thes econd stage until it formed a mountain like shape on the top.
4) It can be concluded that the suitable temperature for baking sponge cake is around 160°C and that for pound cake about 180°C.

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Nagoya-Cochin (Nagoya Breed) is a famous meat breed. It is generally recognized that the chicken meat of Nagoya-Cochin has a better taste and hardness to chew compared with the chicken meat of broiler. The purpose of this study is to elucidate the food histological characteristics of the chicken meat.
Skeletal muscles (m. semimembranosus) of Nagoya-Cochin and broiler were observed under a light microscope with hematoxylin-eosin staining and reticular-silver-impregnation. The cross section of a fiber of chicken skeletal muscular tissue was a polygonal. The polygonal of broiler muscle has more rounded and dull angles than that of Nagoya-Cochin muscle. Reticular fibers located in the endomysium of a Nagoya-Cochin muscle were larger in diameter and more in number than those of a broiler. A reticular fiber of broiler muscle was thin and straight, while that of Nagoya-Chochin was coarse and radial.
These results suggest that the hardness of dark meat in chicken is dependent on the size, number and structure of reticular fiber in connective tissue. A more moderate hardness to chew of Nagoya-Chochin meat as compared with that of broiler can be explained through the observation on histological structure.

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