Proportional parts, amounts of major chemical constituents and interior qualities of the fresh and stored Nagoya-Cochin eggs were examined in comparing with those of White-Leghorn eggs. The interior qualities were determined from the thick/thin white ratios and the pH of each albumen. The breaking strength and apparent viscosity of non-heated egg yolk were studied.
The ratio of egg yolk weight to egg weight and egg yolk index of Nagoya-Cochin were significantly larger than those of egg yolk of White Leghorn. The crude fat, the viscosity, the breaking strength of Nagoya-Cochin egg yolk were 36.93%,2,735mPa·S and 0.065×10⁴pa, respectively, and those of white Leghom egg yolk were 36.13%,1,690mPa·S and 0.050×10⁴pa, respectively. The pH and the thick/thin white ratio of each egg stored for 21 days at 20°C were the same. The morphological characteristics of egg yolk were examined by scanning electron microscope. There were many small size-lipids in yolk spheres of Nagoya-Cochin. It was suggested that the lipid size was concerned with the viscosity of egg yolk.

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The weight of tubers and contents of starch and vitamin C of potatoes (Solanum tuberosum L., cv. Kitaalcari, cv. Irish Cobbler) increased during tuber development and reached maximum at the end of July or at the early August. The activity of L-galactono-γ-lactone dehydrogenase (EC 1.3.2.3, GLDHase) increased during tuber development and reached maximum just before the time when vitamin C content reached the maximum value, and then decreased.
When tubers of 7 cultivar varieties of potatoes including cv. Irish Cobbler, cv. Kitaalcari, cv. Tsunika, cv. Touya, cv. Hokkai 79, cv. Shimakei 575 and cv. Shimakei 571 were stored at 4°C within 10 days after the harvest at about 20°C, vitamin C contents were markedly decreased during one month after storage and then decreased gradually for 3 months by 50∼70%. When tubers were stored at 4°C, both ascorbic acid (AsA) content and GLDHase activity increased after 2 days, and decreased thereafter. The decrease in vitamin C content during cold (4°C) storage was larger than that of storage at 15°C, and GLDHase activity was higher in 4°C-storage tubers than that in 15°C-storage tubers. These results suggest that AsA is supplied by the increased GLDH ase activity when a large amount of AsA is exhausted by a strong low temperature stress.

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Shimetamago is a type of cooked egg that is served as one of the ingredients of Japanese clear soup. It is made by holding a half-coagulated egg in a suitable container covered by cloth after heating in boiling water.
The cooking conditions for shimetamago were analyzed by measuring the toughness with a Rheometer, by SDS-polyacrylamide gel electrophoresis and by a sensory panel test.
When the egg was slid into boiling water (100°C), more proteins coagulated than when slid into simmering water (90°C). The addition of salt to the egg or to both the water and egg accelerated the coagulation of egg proteins. The toughness of shimetamago increased with increasing heating time and final temperature.
The volume of boiling water used for preparation affected the toughness of shimetamago, and 4 to 6 times (V/W) of the egg was needed to achieve best results.
A sensory comparison of shimetamago with or without salt indicates that the taste of one prepared with the addition of salt to both the egg and water was significantly preferred (P<0.01), but that the appearance of one prepared without any salt was significantly preferred (P<0.01). Shimetamago seems to have satisfactory appearance and taste, when salt is added to the egg and not to the water.

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The degree of bacterial contamination and the effect of washing on reduction were tested for garnish vegetables, such as Japanese chive, radish sprouts, perilla, parsley, and cherry tomato. After confirming that the most probable number method (MPN) is substitutable for the standard plate counts, total viable counts were determined by MPN. Cherry tomato had 10³ cells/g without coliform bacilli, while other vegetables had from 10⁵ to 10⁷ cells/g with coliform bacilli. Washing by running tap water for 30 seconds decreased the bacterial contents from 1/2 to 1/100 for the samples of smooth surface, namely, root of Japanese chive, radish sprouts, cherry tomato. But for others, significant differences were not seen between the unwashed and washed. Coliform bacilli were not removed from garnish vegetables by washing in tap water.

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This paper is the result of a questionnaire survey about preparing and eating the New Year's special dishes, conducted in 1996 in order to clarify the change of traditional dietary custom in Japan. Most Japanese seemed to keep on practicing the custom from the fact that more than 90% of the total respondents had the dishes, zoni and osechi. Among some respondent's families of younger generation, however, another traditional special drink, toso, was just prepared for ceremonial sake or not prepared at all.70% of the respondents bought some dishes for osechi on sale at shop instead of preparing them by themselves at home. These facts suggested a trend of simplification of the dishes and diffusion of home meal replacement.
Formerly each family used to have its own style for preparing special dishes and hand it down from mothers (mothers-in-law) to daughters (daughters-in-law). Some of the respondents' families had their own styles of the traditional special dishes handed down to them from their ancestors. But since, in more than 50% of the respondent's families the special dishes are prepared by a housewife alone, this suggests the difficulty of transmitting such traditional families' dishes to next generation. Further we could find a tendency that among the younger generation, the preparation of such special dishes are not related to the gender's role difference.

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Experiments were conducted to determine the difference in microstructure between Nagoya-Cochin (NC) and White Leghorn (WL) eggs.
In order to characterize the microstructure of the NC yolk, the size and shape of the yolk sphere were measured by using image processing techniques and compared to those of WL eggs. Two kind of egg were used: 1) 15 NC eggs, and 2) 6 MS-sized WL eggs from chickens receiving the same diets. Each egg was steamed for 15 min, and the yolk was removed and weighed. The yolk was divided into the outer, middle, and inner layers, which were each immersed in the fixation solution. The yolk samples were dehydrated by graded ethanol, and yolk spheres immersed in 100% ethanol were observed with an image processor. These parameters were measured for about 150 yolk spheres per sample: the transverse sectional area, the ratio of long to short dimensions, and maximum dimension. Other yolk samples were also observed by scanning electron microscopy.
The results reveal that the weights of NC eggs and NC yolks was not significantly different from those of WL eggs. The average transverse sectional area of the middle layer of the NC yolk spheres was 4502μm², and of the WL yolk spheres was 7027μm². The NC yolk spheres were thus significantly smaller than the WL yolk spheres, while the ratio of long to short dimension of the NC yolk spheres was also smaller than that of the WL yolk spheres.
The size of the yolk spheres thus varies according to hen strain.

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