应用LGR液态水稳定同位素分析仪测量葡萄酒中的稳定同位素比值18O/16O和δ18O

      LGR的专利技术—利用腔增强激光吸收光谱法，记录高吸收光谱，能够精确的测量葡萄酒中的同位素比值。LGR拥有专业的光谱污染标识软件（软件测量植物水的精确数据在权威期刊上发表过），这使得仪器可以测量葡萄酒中的甲醇和乙醇污染物，从而得到可靠的同位素比值数据。

 

 

Manish Gupta1    J Brian Leen1    Elena Simone    Franklin Berman1    Aldo Ciambotti2

1Los Gatos Research, Mountain View, CA, USA;

2Consiglio per la Ricerca e la Sperimentazione in Agricoltura, Centro di Ricerca per l’Enologia, Asti, Italy

 

Abstract: Wine counterfeiting is an international, multi-billion dollar issue, with some estimates suggesting that up to 5% of wines sold at auctions or secondary markets are fraudulent. Isotope ratio mass spectrometer (IRMS) measurements of the 18O/16O stable isotope ratio (δ18O) of water-in-wine have been used for wine authentication; however, these analyses are time-consuming and costly. In this preliminary study, off-axis integrated cavity output spectroscopy (OA-ICOS) is used to quantify δ18O in wines. This laser-based method has been extensively used to study water isotopes for hydrological and medical applications. Recently, the development of a spectral contaminant identifier (SCI) has extended the application of these OA-ICOS analyzers to contaminated water samples (eg, plant, soil, and leaf waters). Here, we utilize OA-ICOS with the SCI to characterize wine samples (9%–15% ethanol), and show that the laser-based instrument provides a δ18O measurement precision of ±0.07‰ (1σ) and agrees with IRMS to within ±0.63‰ (1σ). Moreover, by training the SCI on isotopically-characterized wines, the agreement with IRMS improves to within ±0.30‰ (1σ). The utility of the instrument is demonstrated by measuring watered and mixed wines. The method presented here can be readily extended to address other food authentication applications.

Keywords: wine isotopes, wine fraud, counterfeit wines, OA-ICOS

 

查看原文：Laser-Based Measurements of 18O16O Stable Isotope Ratios in Wine Samples