Wine and cider vinegars were experimentally manufactured from commercial grape and apple juices, and differences in fatty acid components were analyzed among fermentation stages. Following alcoholic fermentation of Bailey A (a grape variety for red wine) juice, the increase in the proportions of palmitic and stearic acids was found to be accompanied by relative decreases in those of linoleic and linolenic acids. Reversed phase HPLC analysis showed a notable increase in a peak corresponding to oleic acid during acetic acid fermentation, although changes in fatty acid components were slight compared with those during alcoholic fermentation. In the case of Koshu (a grape variety for white wine), no significant difference was observed in fatty acid composition between the juice and its fermenting liquid (wine). However, after acetic acid fermentation, the vinegar produced had a fatty acid composition that was qualitatively and quantitatively similar to that of Bailey A. During alcoholic fermentation of apple (Delicious variety) juice, an increase in oleic acid and a decrease in linoleic acid were observed, followed by increases in palmitic and stearic acids after acetic acid fermentation, similar to changes observed during wine vinegar manufacturing. Thus, we found that juices with characteristic fatty acids produce vinegars with roughly corresponding compositions. Moreover, capillary-GC analysis of fatty acid methyl esters showed that cis-vaccenic acid (an oleic acid isomer) originating from acetic acid bacteria can be transferred into vinegars made by the acetic acid fermentation process. cis-Vaccenic acid was also detected in ten varieties of commercial wine and cider vinegars with cis-vaccenic acid/(oleic and cis-vaccenic acids) ratios of 0.07-0.59.

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RBL-2H3 rat mast cells were stimulated to secrete intracellular granules through multivalent binding of antigen to receptor-bound IgE and preferentially used for anti-allergic evaluation. β-Hexosaminidase stored in the granules was used as a marker of mast cell degranulation. We developed a simple screening method to evaluate inhibitory effects of mast cell degranulation by efficient measurements of the enzyme activity in a continuous 96-well format. The cells were inoculated into a 96-well plate (2.5×10⁵/well) and cultured overnight. Anti-dinitrophenyl-IgE, food extracts and dinitrophenyl-human serum albumin were successively added and incubated for each optimized interval of time. The supernatant was transferred to another well, and the cells were lysed with a passive lysis buffer instead of conventional sonication. β-Hexosaminidase activity in the supernatant and the cells was measured using a color formation substrate with a microplate reader. The percentage of degranulation was calculated from the ratio of the enzyme activity (supernatant/cells). The proposed method can be easily completed by a multi-channel pipetting operation and adapted for high-throughput screening (21 samples/plate, n=2) as compared to the conventional 24-well based method (3 samples/plate, n=2). Reproducibility was also improved from RSD 12.3% to 5.4-9.0% (within-run, n=4). The results agreed well with those of the previous method.

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The velocity of swallowed food passing through the pharynx was measured by the ultrasonic pulse Doppler method. Water with thickening agents and commercial foods for dysphagic patients were compared to control foods, including water, which individuals with dysphagia easily aspirate into the trachea, and yogurt and gelatin, which can be swallowed safely. The relationship between the dynamic viscoelasticity of the food and the velocity measured by the ultrasonic method was examined. The maximum velocity of water on the average of velocity for of nine subjects was about 0.5m/s and that of yogurt was about 0.2m/s. The maximum velocity of water with thickening agents decreased with increasing agent concentration, approaching that of yogurt ; the maximum velocity of all commercial foods for dysphagic patients was similar to that of yogurt. The maximum velocity of foods for dysphagic patients with a storage modulus more than 100Pa or with a dynamic viscosity more than 1Pa·s was almost 0.2m/s, which was similar to that of yogurt. These results show that the risk of dysphagic patients to aspirate food into the trachea can be predicted by the magnitude of dynamic viscoelasticity of the food.

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To investigate the physiological function of a high content of inulin in jumbo leek, the effects of freeze-dried, odorless jumbo leek with an inulin content of 60% (PSII) on the blood glucose level and biochemical markers in blood in streptozotocin (STZ)-induced diabetic rats and the liver damage in acetaminophen (AAP)-treated rats were studied. In the first experiment, rats were fed PSII for two weeks following a one-week STZ (60mg/kg) treatment. Oral glucose tolerance tests (OGTTs) were performed on days 7 and 14. Biochemical markers in blood were measured on day 14. In the second experiment, rats were fed PSII for two weeks and then administered AAP (500mg/kg). After 24h, liver-damage markers and the activities of blood aspartate transaminase (AST) and alanine transaminase (ALT) were measured and a histopathological examination of the liver was performed. In the first experiment, the elevation of blood glucose level in OGTT was suppressed by feeding rats 8.3g PSII (5g inulin)/kg per day. Among the biochemical markers, total cholesterol and triglyceride levels rose in STZ-treated rats compared with control rats. PSII fed to STZ-treated rats lowered these two marker levels below those of the control rats. AST and ALT activities tended to decrease, suggesting that PSII ameliorated liver damage. In the second experiment, AST and ALT activities as well as the histopathological examination of liver confirmed that PSII (2 g/kg per day) protected rats from liver damage before AAP treatment.

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To investigate the effects of storage temperature on flavor of stone-milled buckwheat flour, sensory evaluation and instrumental analyses were performed for sets of buckwheat flour stored in Kraft bags for 7 days at different temperatures. In the sensory evaluation, the sample of buckwheat flour stored at relatively high temperatures (>10°C) showed low scores in total flavor, with an increase in bitterness and a decrease in aroma. However, the samples of buckwheat flour stored at 5°C showed low scores in bitterness and hardness. In the instrumental analysis using taste sensors, significant differences were found in acidity and bitterness, depending on the storage temperature. In particular, the samples of buckwheat flour stored at 5°C had weaker values in the texture analysis, as well as different values in flavor sensor outputs, compared with those at other temperatures. These findings indicate that except for 5°C, relatively low storage temperatures are suitable for preserving the flavor of the buckwheat flour. Finally, we found correlations between the measurements from the instrumental analyses and the sensory evaluation, including those between the texture analysis and hardness and between the GC-MS area analysis and smell. These results suggest that the instrumental analyses utilized in this study are valid for evaluation of flavor of stone-milled buckwheat flour.

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Spontaneously hypertensive rats (SHR/Izm) were fed a 10%-germinated lotus experimental diet for 10 weeks to elucidate the effect of germinated lotus on blood pressure and emotion, as well as plasma lipid and blood glucose levels. Germinated lotus intake significantly lowered the systolic blood pressure at week 10 (p<0.05) and extended the stay time in the center area during the open field test (p<0.01). While plasma insulin, C-peptide, leptin, and resistin levels were significantly increased with germinated lotus intake, plasma lipid, blood glucose, and adiponectin levels were unchanged. These results indicate that germinated lotus intake may affect blood pressure and animal emotion.

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[in Japanese]

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