Plums of 8 varieties (Early Rivers, Sun Prune, Robe de Sargenant, Chairn, Opal, Sunctus, Purple Ais, President) cultivated in Hokkaido in 2002-2004 underwent polyphenol extraction using 5% formic acid methanol, and amounts of polyphenol yielded and antioxidative activity were compared. Significant differences were observed between crops of different years. The Chairn and Sunctus varieties had the highest polyphenol content. These varieties also showed the highest combined antioxidative activity. Although there was a low correlation coefficient between the quantity of polyphenol monomers yielded and antioxidative activity, there was a high correlation between the amount of polyphenol polymers and antioxidative activity. Quantities of polyphenol polymers were calculated by subtracting the quantity of polyphenol detected by the HPLC method from the total amount of polyphenol as calculated by the Folin-Denis method. These results indicate that the main constituents responsible for antioxidative activity in plums are polyphenol polymers. In addition, the polyphenol content of plums cultivated under open-field and closed-field conditions (the latter excludes rain) were examined over 3 years. The results revealed that there was little change in the polyphenol content of closed-field-cultivated fruit throughout the year.

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A new type of noodle that is pre-cooked (gelatinized) in the center only, leaving the surface uncooked (ungelatinized), was produced using microwave heating at 2450 MHz. Temperature distribution in the noodle during microwave heating varied with diameter. When the noodle with a diameter of 15 mm was heated, the temperature at the center of the noodle reached 60°C in 1 min, while the surface temperature was 40°C. As a result, the starch granule could be gelatinized only in the center of the noodle. Starch granules in the noodle were confirmed to be gelatinized using polarizing microscopy. On the other hand, heating the noodle with a diameter of 7 mm produced a rapid increase in temperature with microwave irradiation, and the difference in temperature between the center and the surface was small. Though we tried to gelatinize only the center of the noodle with a diameter of 7 mm by microwave, the entire cross-section of the noodle was gelatinized. In order to gelatinize only the center of the 7-mm noodle, we utilized the difference in dielectric characteristics of the microwave between ice and water. That is, we froze only the surface of the noodle (the center remained unfrozen), heated the sample by microwave, and confirmed by polarizing microscopy that starch granules in the noodle were gelatinized while the surface molecules were not.

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By applying the correlation diagrams of instant elasticity E₀ and constant viscosity η_N of the creep parameter, the physical properties within different types of gel-type processed foods can be determined. In sausage, E₂ decreased, and η_N remained unchanged by cooking. Regarding the relationships between creep parameter and sensory evaluation score, the texture preference of sausage before cooking correlated with elasticity E₂ (r=0.619). On the other hand, the texture preference of sausage after cooking highly correlated with retardation time, τ (τ₁=0.917, τ₂=0.887).

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The hardness of the outer layer (H1) and of all layers (H2) of cooked Japanese wheat noodles was studied using a Tensipresser compression tester. The H2 values of cooked strands of No.1-Hiyamugi (machine-made), Sanuki-udon (machine-made), and Inaniwa-udon (hand-stretched) after standing for 0.5 hours were found to be 1.9N, 2.5N and about 4.0-7.1N, respectively. Both H1 and H2 changed with elapsed time for some noodles, but the H2/H1 ratio assumed a fixed value : about 10 for No. 1 Hiyamugi, about 8 for Sanuki-udon, and about 13-18 for Inaniwa-udon. Proton NMR micro-imaging (MRI) of the cooked Inaniwa-udon showed cavities in the direction of stretching that persisted for more than 6 hours.

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Inactivation of microorganisms and pectinesterase (PE) in fruit juices by supercritical CO₂ was investigated. For this experiment, an original device equipped with a mixer for mixing CO₂ into juices and a zigzag steel pipe (φ 10 cm × 12 m) for keeping CO₂ in a supercritical state (40°C, 100 kg/cm²) was constructed. Four kinds of fruit juice (orange, grapefruit, grape and apple) were treated with this device. When the juices were mixed with CO₂ at a rotation speed of 400 rpm, the viable cell count of each juice was reduced to 1/10 of the initial number. In addition, in the orange juice treated at a rotation speed of 800 rpm, viable cell and yeast counts were remarkably reduced to 1/100 and 1/1000 of the initial values, respectively. Residual activities of PE in each juice treated by supercritical CO₂ decreased by values varying from 0 (grape) to 34% (apple) when treated at a rotation speed of 400 rpm. The sugar, organic acid and free amino acid contents of orange juice treated by supercritical CO₂ at a rotation speed of 800 rpm were approximately equal to those of non-treated juice. When treated orange juice was stored at 5°C, the quality of juice was maintained at a high level for 21 days.

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We investigated quality maintenance in the preservation of germinated rice which had been dried at 35°C to avoid damage due to high-temperature drying. Germinated rice was packed with or without deoxidant. The γ-aminobutyric acid (GABA) contents of the samples packed with or without deoxidant were not observed to be different, and microorganisms did not grow. Oxidant contents in the packs without deoxidant significantly decreased after two months, and the germinated rice deteriorated. After six months, the fat acidity index of the germinated rice packed without deoxidant increased from 23 to 52KOHmg/100g, and an oxidized smell was noted. In addition, the chemiluminescence (CL) intensity of germinated rice packed with deoxidant remained constant for six months, but decreased in the samples packed without deoxidant. These results suggest that the maintenance of high quality in germinated rice under these dry conditions may be attributed to preservation with deoxidant. Measurement of CL intensity proved a simple and useful method of evaluating the quality of the rice.

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The effects of an extract from Phellodendron amurense Ruprecht (Phellodendri cortex) and its component berberine on the differentiation of 3T3-L1 mouse preadipocytes were studied. The extract and berberine suppressed both the accumulation of triglyceride and the activity of glycerol-3-phosphate dehydrogenase (GPDH). We concluded that berberine, a component of Phellodendri cortex, plays an important role in the differentiation of adipocytic cells.

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1. Dark-colored and control samples of 4 varieties of domestically produced wheat flour were measured and compared using L* value as an index flour color darkness and its free amino acids content.
2. The free tryptophan content and the L* value measurements of a flour sample made by two methods of estimating darkness of flour color decreased simultaneously, but there was no relationship between the content of other free amino acids and the L* value of flour.
3. Correlation between free tryptophan content in domestically produced wheat and L* value as the index of flour color darkness was observed, with the range of coefficient of positive correlation being between 0.73-0.93. Therefore, the above results suggest that of free amino acids, only tryptophan is related to color in domestically produced wheat flour.

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Thinned-out young bitter gourds grown in Okinawa Prefecture were juiced using a twin-screw press in order to find a new use for the vegetable and to produce nutritious food products. Bitter gourds were juiced to separate juice and pulp, with a resulting weight ratio of 8 : 2. Almost all vitamin C in the bitter gourds was retained through the juicing process and was retained in a ratio of 8 : 2 (weight of juice/weight of pulp). Processing by the twin-screw press had a throughput of 40 kg/h and had an electrical power demand of 0.091 kWh per 1 kg of juice produced. Both juice and pulp products can be used as nutritious and low-priced food ingredients, which are rich in vitamin C.

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Quantitative differences in free amino acids and γ-aminobutyric acid (GABA) in the cotyledon of immature seeds harvested at 35 days after flowering (DAF) of six vegetative-type soybean (Edamame) and two grain-type soybean cultivars were examined. The concentration of GABA varied greatly among cultivars. Immature seeds of two vegetative-type soybean cultivars, Shirayama-dadacha and Wase-shirayama, contained GABA at more than 50 mg/100 g on a fresh weight (FW) basis. The free amino acid compositions differed between the cotyledon and hypocotyl (radicle-plumule axis) of the immature seeds of Shirayama-dadacha. The concentration of total free amino acids in the cotyledon of immature seeds increased until 30 DAF and then gradually decreased as the seeds matured up to 50 DAF. GABA content was highest at 15 DAF at over 50 mg/100 g FW, and it remained high until 35 DAF, after which it decreased until 50 DAF. Expression of glutamate decarboxylase (GAD) mRNA was examined by Northern-blot analysis and was shown to be highest at 15-35 DAF and decreased until 50 DAF. The expression pattern was almost parallel with the GABA content during seed development.

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