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51.
Benchmarking laboratory‐scale pomegranate vinegar against commercial wine vinegars: antioxidant activity and chemical composition 下载免费PDF全文
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Shu Y. Sun Wen G. Jiang Yu P. Zhao 《International Journal of Food Science & Technology》2012,47(1):100-106
To compare the influence of cultivars on the production of aroma compounds and polyphenols, eight cherry varieties (six sweet and two sour) were fermented into cherry wines, and their compositions were analysed. Results showed that by headspace solid microextraction coupled to gas chromatography–mass spectrometry (HS‐SPME‐GC‐MS), a total of twenty‐first aromatic compounds, mostly consisting of esters, acids, terpenoids and C13‐norisoprenoids, were identified, and eleven polyphenols including five anthocyanins and six phenolic acids were quantified using HPLC. May Duck and Early Richmond wines contained significantly higher levels of phenolic acids (>42 mg L?1) that were associated with high contents of chlorogenic and neochlorogenic acids and also relatively high amounts of octanoic acid and β‐damascenone (odour activity values ≥1000). Hongdeng, Zhifuhong and Bing wines were characterised by higher concentrations of anthocyanins (>41 mg L?1) and also relatively higher levels of isopentyl acetate. Lapins and Governer Wcod wines were distinguished by lower concentrations of polyphenols and relatively higher contents of ethyl 3‐methylbutanoate. 相似文献
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María J. Aguirre Mauricio Isaacs Betty Matsuhiro Leonora Mendoza Leonardo S. Santos Simonet Torres 《Food chemistry》2011
Anthocyanins in aged Cabernet Sauvignon red wines were studied by HPLC–MS. The major anthocyanin in 6, 7, and 8 year old red wine extracts was the dimer vitisin A produced by condensation of malvidin-3-O-glucoside mediated by pyruvic acid. In aged wine, the content of malvidin-3-O-glucoside decreased with age with a concomitant increase of vitisin A. The latter is accompanied by several condensation products with molecular weight up to 1500 m/z. Differential pulse voltammetry indicated that aged wines have lower antioxidant capacity than young wine (400 mV), but higher than malvidin-3-O-glucoside (483 mV). Tafel’s plots showed that the electrochemical process occurring in aged wines is different from young wines. Six, seven and eight year old wines show similar behaviour with plots of 234, 177 and 188 mV/dec, respectively. These values are higher than the expected 120 mV/dec corresponding to a first electronic transfer but smaller compared to the 523 mV/dec corresponding to young wine. 相似文献
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设计手法是落实设计构思、解决设计矛盾的技巧或手段,具有很强的可操作性,在室内设计中设计师运用独特的设计思维,表达出独具一格创作构思。本文笔者结合自己设计作品——中国顶级豪宅《汤臣一品》,做详细的分析,从室内整体格局到客厅、餐厅、主卧、主卫、走廊、工艺等几方面进行剖析。 相似文献
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以巨峰葡萄为原料,选用果胶酶对葡萄汁进行澄清处理。利用低温真空浓缩法研制适合酿造葡萄酒的浓缩葡萄汁,再添加酵母进行发酵。测定发酵后有机酸的变化,结果FFCC2185和FF-CC2186菌种进行葡萄酒发酵的酒石酸含量分别是1.28 g/L和1.38 g/L,苹果酸含量分别是7.21 g/L和7.23 g/L;乳酸,柠檬酸,琥珀酸含量都少于1 g/L。 相似文献