The relationship between the softening of yuzu and the extraction of pectin during soaking in citric acid, heating or pressurization was investigated. Firmness of peel was greatest to least; pressurized>soaked for 24 hrs at pH 2.7>heated, respectively. The cell walls did not loosen after pressurization. However, after heating, the middle lamella of albedo separated but flavedo did not. The amount of pectin was greatest to least in albedo>flavedo>segment walls>juice sacs, and in flavedo, raw>pressurized>heated>soaked at pH 2.7>boiled flavedo. About 24% of pectin was extracted by soaking at pH 2.7. By soaking, peel softened due to the removal of Ca²⁺. The pH values of peel and cooked water were 3-4 and 4.02, respectively. Therefore, it was found that degradation of pectin by heating was mainly from hydrolysis and not by trans-elimination.

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We evaluated 17 kinds of commercial wet rice cracker (nure-senbei) made from 9.8-28.7 g/100 g of water with 0.38-0.81 of water activity that differed in the manufacturing method, degree of moisture, and texture. These products were classified into four types: deep-fried senbei, fairly dry senbei, moist senbei and moist okaki according to the effect of controlled moisture on the water content and textural properties. A sensory evaluation was performed on selected products of three types. Those that broke easily were liked, while the hard texture of fairly dry senbei and the taste of heavily seasoned okaki were disliked.

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The contents of water, ash, ascorbic acid, and total phenol in 12 Yamatoyasai samples, the traditional vegetables of Nara, were measured. The antioxidant activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and oxygen radical absorbance capacity (ORAC) of the samples were also measured. The water and ash contents were not significantly different between Yamatoyasai and common vegetables, while the ascorbic acid content of some Yamatoyasai samples was lower than that of common vegetables. The total phenol contents of the Sensujimizuna and Hanamyouga samples were respectively 1.8 and 1.5 times higher than those of Mizuna and Myouga. In respect of the antioxidant activity, the DPPH radical-scavenging activity of Sensujimizuna and Hanamyouga was also higher than that of common vegetables. A 1.5-2 times higher ORAC value was found in Udakingobou, Hanamyouga, Kaorigobou, Yamatokikuna, and Sensujimizuna than that in common vegetables. It is clear from the results of this study that a substantial number of Yamatoyasai show higher antioxidant activity than common vegetables.

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We used conventional and eco-cooking methods for cutting and compared the reduction in waste of 50 vegetables frequently used in home cooking. Domestic seasonal vegetables were prepared by the conventional technique, similar to that used at home, in accordance with the method practiced in university cooking classes. For a comparison with the eco-cooking method, we removed the tips, roots, and seeds of vegetables, while retaining the skin. This increased the edible parts of 45 vegetables and reduced the overall waste by 9.1%. Those vegetables that had a particularly high reduction in waste were turnips (33.1%), celery (32.1%), butterbur (27.7%), green onion (26.2%), and broccoli (23.3%). The edible parts of some vegetables, however, may not be appropriate for certain recipes, and accordingly, such other preparation methods as chopping, grating, and parboiling the skins and other hard parts may be necessary to efficiently cook these vegetables.

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A dietary survey was conducted on eating habits which consider the environment. The dietary survey was made of university and high school students, and the results analyzed by a factor analysis. The factors applied were consideration of food production, garbage generation,cooking and food transportation.
The results of the factor analysis indicate that high school students considered food production significantly more than university students, while university students considered cooking significantly more than high school students.The environmental burden could be reduced if every student was more concerned with reducing CO₂ emission when making dietary considerations, and such education is required to modify eating habits.

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We investigated the use of fish and meat by 224 female university students, and how their dietary experience and living arrangements affected such usage. The dietary experience during growing up eating fresh fish increased the preference for fish, even if living in an area far from the coast. The home life of the students played a major role in inculcating food preparation techniques, with fish (53.6%) and meat (62.9%) preparation techniques taught by mothers or grandmothers. School education also contributed, with students responding that they were taught how to prepare fish (27.7%) and meat (18.8%) at school.
The frequency of eating fish and meat varied with the current living arrangements, students who lived alone tending, to eat mainly pork and chicken. The food preparation methods also varied according to the type of living arrangements. The food preparation methods used most often by students living at home included raw preparation for fish, roasting for beef, and deep frying for chicken. The food preparation method used most often by students living alone was sautéing for both fish and meat, and these students did not often use deep frying.

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