As the first step in examining Japanese food sustainability, model menus were selected and their environmental load was evaluated for life-cycle (LC) CO₂ emission assuming, that transportation, cooking and disposal of food ingredients were conducted by the household. The selected menus were toast for breakfast, noodles in soup (ramen)for lunch, and three different, dinner meals: Japanese dishes (dinner 1), Western dishes (dinner 2), and Chinese dishes (dinner 3). LC-CO₂ emission from production of the food ingredients was first estimated, then the emission from transportation and cooking was added, before including the emission from disposal to yield the LC-CO₂ emission for the whole meals. The daily emission associated with the meals, was 8,582g of CO₂ (average for the three days), and this level could have a substantial effect on the environment.

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Lemon flavonoid prepared from lemon peel contains 30% of eriocitrin, a potent antioxidant and a functional food material. Tests were made to determine its influence on stability, taste, and physical properties during the breadmaking process. Sixty-five percent of eriocitrin was retained in the bread, and 78% of the antioxidative activity remained after baking bread with added lemon flavonoid. Bread with 0.50% added lemon flavonoid had a significantly higher specific volume than the control bread (p<0.05). We consider that this improvement was the direct result of adding lemon flavonoid which lowered the pH value and increased the resistance of the bread dough in extensograph measurements. Sensory tests showed that a desirable taste could be retained with the addition of up to 0.50% lemon flavonoid, but larger amounts gave the bread a bitter taste. Lemon flavonoid thus seems to be a useful food material for enhancing the functions of bread.

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Katsuo-dashi (extracted from dried bonito), niboshi-dashi (extracted from dried small sardine), konbu-dashi (extracted from dried kelp) and their combinations in practical concentrations for daily use were prepared to investigate the taste characteristics of Japanese soup stock. Instant-dashi (several products on the market) was compared with each prepared sample.
Katsuo-konbu-dashi (a combination of 2% w/w bonito and 1% w/w kelp) had a higher sensory score than 4%w/w bonito stock, and extending the boiling time to promote extraction did not improve score. The taste components(Gluand 5′-IMP)of niboshi-konbu-dashi(a combination of 2% w/w sardine and 1% w/w kelp)and of katsuo-konbu-dashi were determined, and the synergistic effects reconfirmed by a sensory evaluation. The results of a principal component analysis enabled each single ingredient and combination to be identified by their taste characteristics: bonito stock had a strong, sour taste; sardine stock had a slightly bitter, fishy taste; kelp stock had a mild, sweet umami taste; and stock made from their combination had a more complex taste than stock from the single ingredients.

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There is little information available to consumers about reducing CO₂ emission during household cooking and no specific evaluation method for CO₂ reduction. This study estimates the amount of CO₂ emission associated with different styles of rice cooking and preservation.
The study also investigates the environmental household account to understand the current status and examines ways to control the amount of CO₂ emission. The results show that CO₂ emission associated with rice cooking could be reduced by cooking at the time of eating, and that the emission was increased by keeping rice warm in an electric rice cooker. When freezing cooked rice, the time required for thawing by microwave as well as the amount of CO₂ emission increased as the amount of rice was increased.

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The interaction between rutin and wheat gluten was studied to prevent the loss of functionality and improve the preparation of buckwheat noodles. Different noodle samples containing gluten were prepared by using common, common-tartary blended, and tartary buckwheat flour. The respective rutin contents of these flour types were 23,180, and 1,500mg/100g. The rupture characteristics and structure of each of these samples were analyzed by a rheometer and scanning electron microscope.
The blended buckwheat noodles formed a progressively improved structure as the added amount of gluten was increased, and showed similar rupture characteristics to the common buckwheat noodles. In contrast, the structure of the tartary buckwheat noodles was rough-grained, soft and brittle, even when gluten was added. A decrease in the rutin loss during boiling was confirmed with 10-20 wt% added gluten to the blended and tartary buckwheat noodles by reverse phase liquid chromatography.
These results suggest that resilient buckwheat noodles with high functionality can be prepared by adding 10-20wt% gluten to buckwheat flour containing 180mg/100g of rutin

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The taste of Japanese noodles is related to their physical properties and texture which are affected by the state of starches in the noodles. The effects of tapioka, corn and sago starches added to wheat flour on the properties of the noodles were investigated. The physical properties of these prepared noodles were measured and a sensory evaluation was carried out. The noodles with tapioka starch added had a lower breaking strength and higher extension than plain noodles, the resulting noodles being appealingly soft and extendable. On the other hand, added cornstarch made for hard and non extendable noodles which had a higher breaking strength and lower extension than plain noodles. The markedly different structure of gluten in the raw noodle samples treated with a-amylase was observed by scanning electron microscopy. Active gluten added to the wheat flour and starches resulted in increased breaking energy with all types of starch. The sensory evaluation revealed a preference for the noodles with tapioka starch and active gluten added which induced elastic characteristics.

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Chie Yoneda Motoko Awazuhara Keiko Hatae Frozen blocks of bigeye tuna meat were subjected to different thawing methods: 1) soaking in 3% salt water at 30°C: 2) soaking in water at 30°C: 3) slow thawing at 4°C. There was no difference in parameters such as the proportional weight decrease or color change between method 1 and method 2 when the quality of the meat was identical. A sensory test using high-quality tuna meat revealed that the meat thawed by method 1 was weaker in wateryness, while stronger in viscosity, saltiness, and umami taste than the meat thawed by method 2. The sodium chloride concentration in the outer part of sliced samples thawed by method 1 was significantly higher than that thawed by methods 2 and 3. It is concluded that infiltration of sodium chloride into the tuna meat resulted in the higher viscosity and the improved of umami taste.

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The viable count, coliform count and E. coli count were determined in commercial vegetable saladsamples to establish standard guidelines for hygiene monitoring. A chromogenic agar tricolor medium was compared with a conventional desoxycholate agar medium for identifying and quantifying the coliforms in commercial vegetable salad. The coliforms were measured on both agar media.
The viable count of 100 commercial vegetable saladsamples had a wide range 10-10⁶cfu/g,82(82.0%) and 97(97.0%) of these samples being coliform positive when using the desoxycholate medium and agar tricolor medium, respectively. Ninety-seven of the coliform- positive samples were contaminated in the range of 10-106 cfu/g. E. coil was positively detected in 6 (6.0%) of the 100 commercial vegetable saladsamples in the range of 10-10⁴cfu/g.
The chromogenic medium enabled rapid one-day measurement of coliforms and E. coil in perishable vegetable salad.
The bacteria of 35 coliform-positive colonies that grew on the agar tricolor medium were identified as 10 species, including Klebsiella pneumoniae (9 strains).

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