The texture and taste of Vichyssoise soup cooked by a professional chef (VP) and that produced by a food manufacturer (VM) were compared by examming their physical properties in order to investigate the optimum cooking conditions for making desirable Vichyssoise soup.
In comparison with VM, VP was lower in apparent viscosity, larger in potato-cell size, and higher in the ratio of particle volume. Micro-structural observations showed that the starch particles in VP were retained in the potato cells, whereas those in VM had leaked from the cells due to severe cell damage.
It was found that soup like the VP sample could be obtained by a straining the potatoes at 90°C through a sieve of 250μmin mesh size-which minimized damage to the potato cells by and made a product lower in viscosity and higher in particle volume than the VM sample.
A sensory test was carried out on two products made by different processing techniques. The mixing method was found to damage the cells more and spoil the texture of the potatoes. The straining method with a sieve, however, gave favorable results, producing a soup that was less viscous, and that retained the potato particles, while still being smooth in the mouth.

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The processes used by a French chef and a non-professional to prepare white sauce were compared to identify those factors which would give desirable physical properties to the resulting sauce.
The main difference lay in the process of mixing the roux and milk. It was found that the professional stirred the mixture at twice the speed of the non-professional. Oil and starch were finely dispersed in the chef-made sauce which was lower in the yield stress, thixotropic paremeter and consistency index, and higher in the flow behavior index than the other. In the sauce made by the nonprofessional, oil was dispersed in larger grains, and the starch particles cohered. The sensory test results showed that the chef-made sauce was more favored than that of the non-professional because of its lower viscosity and smoother and softer texture.
Several sauces prepared with different stirring speeds were examined. As the stirring speed was increased, the dispersion and physical properties of the sauce contributed to the better evaluation of taste. Smoothness, which greatly contributed to the evaluation of taste, was well correlated with the consistency index and with the size of the starch and protein particles.
The higher speed by the professional in stirring the mixture of roux and milk therefore resulted in preferable physical properties of the white sauce-in which starch and oil were finely dispersed.

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Fresh and stored shell eggs(up to 6 days at 25°C) were heated through a temperatures range from 20 to 80°C for 48 min in water with several NaCl concentrations (0,1 and 20%). The rheological properties of prepared egg yolk gels were examined according to the Voigt six elements mechanical model. The egg yolk gels from fresh shell eggs heated in water without NaCl were found to be lower in hardness and higher in elasticity compared to gels from the eggs heated with NaCl. With increasing storage days of eggs, the hardness, elasticity and viscosity of the egg yolk gels tended to decrease, and became more susceptible in deformation and flow. In the electrophoregrams of egg yolk gels, the intensities of the β-livetin and transferrin decreased for the eggs that had been stored for 5 days.

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Tastes of Japanese dishes are formed from fermented seasonings which each contain a unique flavor.
Among such seasonings, mirin and shoyu have been used for Japanese cooking since the Edo period.
Mirin, which provided the characteristic flavor of Edo cooking, has become one of the key ingredients in Japanese cuisine.
Cooking books and articles published during the Edo period were studied to present this report on use of mirin and its development for Japanese cooking.

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We first carried out a questionnaire survey among female junior college students in Nagasaki Prefecture and those in Osaka Prefecture where lightly-flavored foods are preferred to clarify the differences in the amounts of sugar and salt used for seasoning. Next, the students cooked with the amounts of seasonings they usually use to evaluate individual preferences for the sugar: salt ratio in the food.
The questionnaire revealed that families in Nagasaki Prefecture use more sugar in various foods than the families in Osaka Prefecture.
When the amounts of salt and sugar added by each student for the preparation of several dishes were determined, the sugar: salt ratios of 3 of the 5 dishes prepared by students in Nagasaki prefecture were higher than those in Osaka prefecture.

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The effects of the storage temperature of Niboshi on the flavor and content of the extractable components of Niboshi soup stock were investigated.
Three bunches of Niboshi were respectively preserved at 25°C,5°C and-25°C for up to 90days.3%Niboshi soup stock was used for a sensory test and for determining the extractable components, lipid oxidation and color tone.
Preservation of Niboshi for 10 days resulted in little effect of temperature on the taste and the contents of extractable components in the soup stock.
However, preservation for more than 30 days resulted in a loss of the smell of the Niboshi soup stock preseved at 25°C. In the case of preservation for more than 60 days, the higher the storage temperature, the lower was the sensory evaluation of the soup stock.
It is presumed that lipid oxidation induced browning of the Niboshi.
This reduced the sensory evaluation score of the soup stock due to the bitter and more intense fishy taste.

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The effects of potato starch and modified (hydroxypropylated and cross-linked) potato starch on breadmaking properties were studied. Potato starch or modified starch was blended with wheat flour at the ratio of 0 (control),10,20 or 30% for breadmaking. The water absorption tested by a Farinography was decreased by blending each starch and particularly by blending the potato starch. Blending with 30% of modified starch resulted in lower gas production, and the loaf volume decreased with increasing blending ratio of the starch. The crumb of bread made from wheat flour with potato starch was higher in hardness and lower in cohesiveness than that made from the control without starch, while blending with modified starch resulted in higher levels for both properties. A discontinuous gluten network was apparent in the bread made by the blending with each type of starch.

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The crust of manjyu (a bun filled with sweetend bean past) was prepared from wheat flour, which provides most popular and simple composition, baking powder and various proportion of water and sugar, and the effect of the composition was studied on its properties.
Obserbation of the appearance and cross-section of manjyu showd that too little water and sugar produced small and hard buns, while too much water and sugar produced buns that were too soft and did not hold their shape, neither being fit for the manjyu crust.
The puffing ratio increased with increasing proportins of water and sugar. While the hardness of textural measurments decreased with increasing proportions of water and sugar.
Organoleptic tests on the crusts of wheat flour manjyu containing bean paste showed the preferance for water addition of 30∼35% and sugar addition of 50∼60% in respect of the softness, taste and total evaluation.

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Changes in the 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity and the ascorbic acid content of commercial beverages (green tea, vegetable juice, sport drink, and coffee) during preservation were investigated. The beverages were preservedat 5°C,25°C, and 35°C in the air or in a vacuum. The decrease in radical-scavenging activity and ascorbic acid content was found to be greater with increasing preservation temperature, this being more apparent in the air than in a vacuum. Long-term preservation, however, resulted in the radical-scavenging activity and ascorbic acid content decreasing even at a low temperature in a vacuum. Those beverages with a higher content of sugar retained a high level of ascorbic acid, which may have been due to the protective effect of sugar against ascorbic acid oxidation.

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Miso paste samples were prepared from five kinds of commercial miso with the addition of sugar and water.
The difference in degree of browning between before and after heating the paste that had been prepared with barley miso B was the greatest. However, the color difference between miso B and miso paste B was the least, while that of D was the greatest. The value of storage modulus G' for each miso paste was less than that of the corresponding miso, this reduction being particularly marked with miso A and C.
The antioxidative activity toward linoleic acid of each paste was higher than the original miso, that of miso paste A being the highest. The antioxidative activity toward linolenic acid was highest for miso paste B. The correlation coefficient obtained from the difference before and after heating of the antioxidative activity toward linolenic acid and of the browning degree was 0.8329, but this was not significant. The rate constant of miso paste D at various heating temperature tended to be high, while the activation energy of miso paste A was the highest and that of miso paste B was the lowest.

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To clarify the dietary trend in New Year food, a survey was made on dietary habits during the three days of the New Year of women students. The dietary habits for last 20 years since 1978 were surveyed in respects of Zoni and other traditional Japanese dishes, using a total of 447 women's college students living in Ishikawa and its surrounding area. These subjects comprised 95 students on the roll in 1978,71 in 1984,100 in 1991 and 181 in 1997-1998. The results indicate that the New Year habit of eating Zoni still continues, however, it is not now eaten on all days of the New Year, although such a habit was common for most people in the past. The mean number of individuals eating Osechi was found to be decreasing, although almost all responders ate Osechi at least once during the three days. There was a decrease in the frequency of eating such dishes on the second and the third days compared with that on the first day. These results suggest that the traditional custom of eating Zoni and Osechi dishes would be gradually lost in future, but that the habit would continue merely in their ceremonious eating on the first day of the New Year.

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[in Japanese]

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