[in Japanese]

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[in Japanese]

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[in Japanese]

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To classify Japanese rum（n＝18）and imported rum（n＝32）, we analyzed 78 volatile compounds by solid phase micro extraction（SPME）, and 6 volatile compounds by direct head space analysis. There was a significant difference in 34 volatile compounds between Jananese rum and rum made in Caribbean contries and bordering the Indian Ocean. In a stepwise discriminant analysis procedure using 6 volatile compounds（1-hexanol, guaiacol, diethyl succinate, 2-methylbutyl acetate, acetaldehyde and furfural）, all of 50 samples were rightly classified. Estimating the accuracy of the discriminant analysis by cross validation, the ratios of appropriate classification were 100 %.
To test the robustness of a discrimination coefficient obtained, a discrimination analysis of Japanese rum and different imported rum（n＝40）provided the ratios of appropriate classification at 92.5 %. We believe that Japanese rum can be distinguished from imported rum with relatively high precision by the discriminant analysis. In addition, the production process of Japanese rum speculated from compounds was given consideration.

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In our previous study, a process in a laboratory scale was developed to produce rice shochu rich in ethyl caproate, ethyl lactate, and isoamyl acetate（flavor-rich rice shochu）. In this study, a pilot scale using a 127 L second-stage fermenter was carried out, with the addition of material rice of 25 kg（koji ratio, 33%; water ratio, 165%）, caproic acid producing bacteria（CAPB）consortium, and lactic acid bacterium（LAB）on the first day of the second-stage fermentation. An ethanol concentration of 130 g/l was achieved on the 7th day of the second-stage fermentation; this then slowly increased and finally reached 142 g/l. With the addition of CAPB consortium and LAB, ethyl caproate and ethyl lactate were produced during the second-stage fermentation and increased with time. The final fermented mash was subjected to vacuum distillation, and a relatively high ethyl caproate recovery efficiency of 325.3% was obtained, which was consistent with the result of the laboratory scale. Odor activity values（OAV）of the flavor compounds were calculated using the flavor compounds contents and their olfactory thresholds, and flavor characteristics of rice shochu with/without the addition of CAPB consortium and LAB were evaluated. The traditional rice shochu generally has a banana flavor, while the flavor-rich rice shochu has the Chinese Luzhou-flavor. The flavor-rich rice shochu has flavors of banana and apple, as well as an acid solution odor. However, the acid solution odor was so light that it did not significantly influence the fruit flavor. This study demonstrated that it is possible to produce flavor-rich rice shochu in a pilot scale.

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The aim of this study was to evaluate whether lateral shoot grapes could be used as an adaptive method for winemaking following global warming. During the early current shoot growth stage of Muscat Bailey A ［Vitis×labruscana （Bailey）and Vitis vinifera（Muscat Hamburg）］, current shoot topping was carried out on May 3, 2014 and May 16, 2015 by removing all flower clusters on the current shoot. The phenology of flowering, coloration, and harvest events occurred 1-1.5 months later compared with untreated vines. The mean maximum and minimum air temperatures from the time of coloration to harvest in the vineyard in 2015 were 5.9℃ and 7.4℃ lower than in controls, respectively. Anthocyanin content in lateral shoot grape skins was more than double compared with that of the control. Thus, anthocyanin contents and color intensity in the wines made from lateral shoot grapes were approximately 1.7-3.0-times and 1.6-2.6-times higher than in control wine made from current shoot grapes, respectively. Additionally, the concentration of volatile components, such as furaneol and γ-nonalactone, were much higher than in control wine. These results suggest that lateral shoot grapes are useful for producing wine as an adaptive technique to global warming.

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