Instituto de Ciencias de la Vid y del Vino (University of La Rioja, CSIC, Gobierno de La Rioja) , Finca La Grajera, Ctra. Burgos Km. 6, 26007 Logroño, Spain.
INOV - INESC Inovação , Rua Alves Redol 9, 1000-029 Lisboa, Portugal.
J Agric Food Chem. 2016 Oct 12;64(40):7658-7666. doi: 10.1021/acs.jafc.6b01999. Epub 2016 Sep 30.
In red grape berries, anthocyanins account for about 50% of the skin phenols and are responsible for the final wine color. Individual anthocyanin levels and compositional profiles vary with cultivar, maturity, season, region, and yield and have been proposed as chemical markers to differentiate wines and to provide valuable information regarding the adulteration of musts and wines. A fast, easy, solvent-free, nondestructive method based on visible, short-wave, and near-infrared hyperspectral imaging (HSI) in intact grape berries to fingerprint the color pigments in eight different grape varieties was developed and tested against HPLC. Predictive models based on modified partial least-squares (MPLS) were built for 14 individual anthocyanins with coefficients of determination of cross-validation (R) ranging from 0.70 to 0.93. For the grouping of total and nonacylated anthocyanins, external validation was conducted with coefficient of determination of prediction (R) of 0.86. HSI could potentially become an alternative to HPLC with reduced analysis time and labor costs while providing reliable and robust information on the anthocyanin composition of grape berries.
在红葡萄浆果中，花色苷约占果皮总酚的 50%，是葡萄酒最终色泽的主要决定因素。花色苷的含量和组成特征因品种、成熟度、季节、地域、产量等因素而变化，因此被提议作为区分葡萄酒的化学标记物，为葡萄汁和葡萄酒的掺假提供有价值的信息。本研究建立了一种基于可见-短波近红外高光谱成像（HSI）的无损、快速、无溶剂的方法，用于对 8 个不同品种的葡萄浆果进行颜色色素的指纹分析，并与 HPLC 进行了对比。采用偏最小二乘法（MPLS）建立了 14 种花色苷的预测模型，其交叉验证（R）系数的范围为 0.70-0.93。对于总花色苷和酰化花色苷的分组，采用外部验证，预测（R）系数为 0.86。HSI 可以替代 HPLC，分析时间和劳动力成本更低，同时可以提供可靠和稳健的葡萄浆果花色苷组成信息。
