Lycopene is found abundantly in tomatoes and processed tomato products and exhibits a strong antioxidant capacity. However, most lycopene found in plants is present in the all-trans form, which is associated with low bioavailability. Contrastingly, cis-isomers of lycopene, which are present in considerable quantities in processed tomato products, are more bioavailable than the all-trans isomer. Recent studies revealed that thermal cis-isomerization of (all-trans)-lycopene is promoted when lycopene is cooked with edible oil and onions. In this study, we found that several vegetables such as onions, garlic, broccoli, and cabbage, which are used frequently to prepare home-cooked tomato-based dishes, promoted the thermal cis-isomerization of (all-trans)-lycopene. We also investigated the effect of onion and broccoli on the lycopene cis-isomer content in generally-cooked tomato-containing dishes. The results clearly showed that the addition of onion or broccoli promoted the cis-isomerization of (all-trans)-lycopene in the dishes.

In this study, we investigated the compatibility between local dishes and soy sauce in Hokkaido. We seasoned ‘imomochi', a local dish of Hokkaido, and tofu with soy 5 sauce produced in three different regions: Hokkaido, Kanto, and Kyushu. Sensory evaluation was carried out with the participation of 286 Hokkaido-resident women belonging to six different generations. The evaluation revealed that imomochi cooked with Hokkaido soy sauce was highly preferred amongst the participants compared to that from other regions. Similarly, tofu seasoned with Hokkaido soy sauce was highly preferred. Furthermore, the data suggest that the taste preference for soy sauce develops around the age of a junior high school attendance. Finally, we found that ‘generation' was the related factor among participants who favored imomochi seasoned with Hokkaido soy sauce. Results imply that the taste preference for local soy sauce develops during the long course of residence in a single location, concomitant with eating habits closely reflecting local culture.

My aims were to examine the compatibility between soy sauces and local cuisines, and to examine the effects of these cuisines on palatability and other aspects. Samples of "Kanto-Style Simmered Daikon Radish," a local cuisine of Kanto, and "Hiyayakko" (cold tofu), a common national cuisine, were examined. Both dishes were made using two types of soy sauce from Hokkaido, Kanto and Kyushu respectively. Sensory evaluation of the two samples involved participants living in Kanto who ranged from infants to the elderly. Moreover, I administered a survey questionnaire soliciting information on dietary practices and other aspects. Concerning the palatability of simmered daikon radish, Kanto and Kyushu soy sauces showed good compatibility. The participants seemed to prefer samples that enhanced taste and aroma of the soy sauces. Additionally, in some cases, it seemed that infants could detect differences in samples and showed preferences. Concerning the palatability of Hiyayakko, one type each of the Kanto and Kyushu soy sauces showed good compatibility. Infants were able to detect differences in samples and, in some case, demonstrated preferences. To explore the palatability of taste and "usual" taste, I examined the relationships with the participants' diets. More participants above elementary school age than infants regarded simmered daikon radish with Kanto soy sauce as the usual taste. In addition, the percentage of participants who preferred the taste of Hiyayakko with Kanto soy sauce was high for those whose home cooking style was associated with the Tokyo metropolitan area. Finally, the percentage of participants who regarded the taste as "usual" was high among those who had lived in the Tokyo metropolitan area for at least 10 years.

We examined the compatibility of soy sauces from Hokkaido, Kanto, and Kyushu with a local dish from Kyushu, named "Dago jiru" based on sensory evaluation by six generations of individuals, living in Kumamoto, Kyushu. Chilled tofu was used as a reference. In addition, we examined the differences among generations in their preference of soy sauces in the dish and the influence of the respondents' diet on the sensory evaluation results using decision tree analysis.

The sensory evaluation results showed the compatibility of "Dago jiru" with soy sauces from Kanto and Kyushu, and that of chilled tofu with soy sauce from Kyushu using Wilcoxon's signed rank test. Generations older than junior high school students recognized the difference caused by the soy sauce in both dishes. The group with a high score only for soy sauce from Kyushu in terms of their taste preference for chilled tofu had been living in Kumamoto for more than 10 years, and were generations younger than adults who ate dishes containing soy sauce more than once in 2 days. Therefore, this study indicated that the individuals' preference for local soy sauce was a result of their dietary habits.

We investigated the influence of batter stirring number with a rubber spatula on the quality and palatability of sponge cake, in which 30% w/w of the soft wheat flour was replaced with pure cocoa powder. The stirring numbers tested were from 20 to 50 in increments of 10, designated as S20, S30, S40, and S50. Cocoa powder (20% w/w) was stirred 50 times and was used as control according to our previous report.

Batter-specific gravity was significantly higher in S50 compared to control. Cake-specific volumes of S20 and S50 were significantly lower than control. There were no significant differences in the hardness of the cake between the control and the experimental cakes. However, the cohesiveness values of S30 and S20 were significantly lower than that of the control. From the measurements of batter-specific gravity, cake-specific volume, and mechanical properties, we concluded that a stirring number of 40 is necessary for the sponge cake containing 30% w/w cocoa powder to obtain a quality similar to that of the control sponge cake.

Bread was prepared using salt-resistant yeast Hyphopichia burtonii M2 isolated from ‘Inaniwa udon'.

It was found that the fermentation was delayed when the saline concentration of the dough was higher than that of the liquid culture of H. burtonii M2. When 2% saline liquid culture of H. burtonii M2 was added to the salt-free bread dough, swelling of the dough was observed without an induction period. The specific volume of the bread prepared using 2% saline liquid culture of H. burtonii M2 ranged between 2.42 to 2.62 (cm³/g) compared to that of the bread prepared with dry yeast (3.15 cm³/g). The bread prepared using H. burtonii M2 tended to harden after two days of baking.