We have developed SSR (simple sequence repeats) markers for identification of tea cultivars developed and registered in Japan using nucleotide information from Camellia sinensis. Among 44 primer pairs investigated, 6 primers were found to uniquely identify tea cultivars. The selected markers were polymorphic, showing 4 to 13 different fragments per marker, and a minimum of 2 markers was sufficient to distinguish all 41 cultivars investigated. In this study, we also tested the detection of cultivar contamination. As a model for contaminated samples, ‘Kanayamidori’ was mixed in ‘Benifuuki’. PCR products amplified by SSR marker 11D02T were analyzed by capillary electrophoresis by means of DNA sequencer. The peak derived from ‘Kanayamidori’ was detected even in a mixing ratio of 2% (w/w). This shows that the present method is useful for the identification of Japanese tea cultivars and can be applied to powdered tea.

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Cookie models were prepared using 3 species of commercial lipids (butter, diglyceride (Econa), triglyceride (canola)) and 2 species of reagent grade lipids (triolein, tripalmitin), and the effects of these lipid additions on the properties of and starches in cookie models was examined.
(1) SEM images showed that starch granules in cookie models are embedded in lipids. The shape of starch granules was similar among lipid species.
(2) Enthalpy of the starches separated from cookie models was less than that of raw wheat starch on DSC analysis, but changes in enthalpy were small. The results suggest that the crystal region in starches separated from cookie models scarcely changed. Gelatinization properties of the starches separated from cookie models were relatively similar among lipid species.
(3) The values of λmax and blue value of the starch samples obtained with iodine color reaction were lower than those of raw wheat starch. High molecular peak in GPC profiles of starch samples were also smaller than that of raw wheat starch. However, the degree of decomposition differed and the extent of peak change widely differed among lipid species. These results suggest that amylopectin in the starch samples of cookie models were primarily decomposed in the baking process.
(4) Viscosity of the starch samples obtained from RVA patterns was lower than that of wheat starch in all cases. However, the order of viscosity among lipid species differed from the order of decomposition extent among lipid species. These results suggest the existence of another factor affecting the viscosity of starch, such as the ability to form inclusion complexes with lipids.

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Freshwater clam (Corbicula fluminea) is consumed as a food stuff that promotes liver health in Taiwan, but scientific evidence for this effect is scarce. In this study, we investigated the effects of freshwater clam extract (FCE) on D-galactosamine-induced liver injury and ethanol-induced acute alcoholic fatty liver in rats. In liver injury induced by D-galactosamine, increased activities of serum aspartate transaminase (AST) and alanine transaminase (ALT) were significantly suppressed by FCE. However, in alcoholic fatty liver disease induced by acute administration of ethanol, liver lipids tended to be reduced by FCE. Hepatic cholesterol concentration was significantly decreased. In addition, we investigated the effect of FCE on ethanol metabolism in rats acutely administered ethanol. Blood ethanol clearance rate was significantly enhanced by FCE. These results suggest that FCE has protective effects on liver injury and fatty liver, and an accelerative effect on alcohol metabolism.

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Changes in anthocyanins, polyphenols and β-carotene in colored (purple or orange) sweet potato miso during production were investigated by HPLC. Acylated anthocyanins (YGM) of purple-fleshed sweet potato decreased after aging, while nonacylated and monoacylated anthocyanins, which were presumed to be the deacylated products of acylated anthocyanins, were increased. For the change in polyphenols, the disappearance of chlorogenic acid and the accumulation of caffeic acid was observed in both misos. Therefore, deacylation caused by koji-mold seems be the main change in anthocyanins and polyphenols during colored sweet potato miso production. β-carotene content of orange-fleshed sweet potato remained at 94.6% after aging, and appears to be relatively stable. In addition, DPPH radical scavenging activity of colored sweet potato miso and commercial miso was assayed and compared. Among the miso samples, the radical scavenging activity of purple-fleshed sweet potato miso was especially high, and its activity became slightly higher compared with the mixture of the ingredients. However, the composition of elements with radical scavenging activity was greatly changed, and the proportion of caffeic acid in total radical scavenging activity increased. These results suggest that the absorption of colored sweet potato miso compounds after ingestion is changed by fermentation and aging.

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Several derivatives of lipid in brown rice were traced under open-air conditions, and methods of peroxide suppression were examined. Peroxide values increased immediately, with a maximum of approximately 50 meq/g. Carbonyl values began to increase after 10 days, while fat acidity began to increase after 30 days. The most effective method for peroxide suppression storage in the shade irrespective of surrounding temperature, and oxygen absorber is also effective as assistant.

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[in Japanese]

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