Cooke Rachel C, Capone Dimitra L, van Leeuwen Katryna A, Elsey Gordon M, Sefton Mark A
School of Chemistry, Physics and Earth Sciences, Flinders University, Adelaide, Australia.
J Agric Food Chem. 2009 Jan 28;57(2):348-52. doi: 10.1021/jf8026974.
Stable isotope dilution assays have been developed for gamma-octalactone (1), gamma-nonalactone (2), gamma-decalactone (3) and gamma-dodecalactone (4) in both white and red wines for the first time. (2)H(7)-analogues of each lactone were prepared for use as internal standards via a strategy employing ring-opening, esterification and oxidation of the respective starting lactones. The methods were shown to be highly accurate and reproducible (R(2) > or = 0.999; SD < or = 1%). A large selection of Australian wines (n = 178) were analyzed for the presence of lactones 1-4. Fifty-eight white wines covering the varieties Chardonnay, Riesling, Sauvignon Blanc, Semillon and Viognier, as well as Botrytis style wines, were analyzed and showed broadly that gamma-octalactone (1) was the most common lactone, being observed above its limit of detection in 28 of the wines, followed by gamma-nonalactone (2) in 23 wines. The Botrytis style white wines had the highest concentrations of 1 and 2 (maximum concentrations 8.5 and 59 microg/L respectively). A total of 120 red wines covering the varieties Cabernet Sauvignon, Durif, Merlot, Pinot Noir and Shiraz were also studied and showed gamma-octalactone (1) and gamma-nonalactone (2) to be the most common lactones present, in 56 and 57 of the wines, respectively. gamma-Decalactone (3) was observed in only a small number (13) of red wine samples and not at all in the white varieties. gamma-Dodecalactone (4) was absent from all 178 samples studied. The highest concentrations of lactones 1, 2 and 3 in the red wines were 4.2, 39.7 and 4.0 microg/L respectively.
首次针对白葡萄酒和红葡萄酒中的γ-辛内酯（1）、γ-壬内酯（2）、γ-癸内酯（3）和γ-十二内酯（4）开发了稳定同位素稀释分析法。通过采用各自起始内酯的开环、酯化和氧化策略，制备了每种内酯的（2）H（7）-类似物用作内标。结果表明这些方法具有很高的准确性和重现性（R²≥0.999；SD≤1%）。对大量澳大利亚葡萄酒（n = 178）进行了分析，以检测内酯1 - 4的存在情况。分析了58种白葡萄酒，涵盖霞多丽、雷司令、长相思、赛美蓉和维欧尼等品种以及贵腐风格葡萄酒，结果大致显示γ-辛内酯（1）是最常见的内酯，在28种葡萄酒中其含量高于检测限，其次是γ-壬内酯（2），有23种葡萄酒含有该内酯。贵腐风格白葡萄酒中1和2的浓度最高（最大浓度分别为8.5和59 μg/L）。还研究了总共120种红葡萄酒，涵盖赤霞珠、杜瑞夫、梅洛、黑皮诺和设拉子等品种，结果显示γ-辛内酯（1）和γ-壬内酯（2）是最常见的内酯，分别在56种和57种葡萄酒中存在。仅在少数（13个）红葡萄酒样品中检测到γ-癸内酯（3），而在白葡萄酒品种中完全未检测到。在所有研究的178个样品中均未检测到γ-十二内酯（4）。红葡萄酒中内酯1、2和3的最高浓度分别为4.2、39.7和4.0 μg/L。
