当前位置: X-MOL 学术Food Anal. Methods › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
ATR-MIR Spectroscopy Predicts Total Phenolics and Colour for Extracts Produced by Microwave-Assisted or Conventional Thermal Extraction Methods Applied Separately to Mixtures of Grape Skins from White or Red Commercial Cultivars
Food Analytical Methods ( IF 2.9 ) Pub Date : 2020-01-20 , DOI: 10.1007/s12161-020-01702-w
Mariola Kwiatkowski , Daniel Cozzolino , Dennis K. Taylor

Abstract

Attenuated total reflectance mid-infrared (ATR-MIR) spectra were collected from 480 grape skin extracts produced in a wide range of conditions. The conditions were created at different phases in parallel response surface RS-optimisation experiments aiming to maximise the total phenolics in red and white grape skin extractions by microwave-assisted (MAE) or conventional thermal (CTE) methods. Skins mixtures for six white and six red Australian commercial cultivars were prepared from grapes collected at veraison and harvest. The total phenolics were measured for individual extracts with the Folin-Ciocalteu method. Partial least squares (PLS1) regression was employed on the spectra to predict the total phenolics (TP) and colour (CIELAB chroma C*) of individual extracts. Models based on the raw spectra and their second derivative (Savitzky-Golay, 20 points) were examined using the full range of spectra 4000–400 cm−1, and sub-ranges: 4000–1100 cm−1, 1500–400 cm−1, 1500–1100 cm−1 and 1457–1168 cm−1. The PLS1 models based on the second derivative of the range of 4000–1100 cm−1 provided the best results for both TP and C*, for each skin colour. Overall, the residual predictive deviation (RPD) exceeded 3.0, indicating the PLS1 models’ ability for fair classification, suitable for screening. A comparative analysis was performed for the range of 4000–1100 cm−1 between the spectra of white and red skin mixture extracts: the peaks at 3840 cm−1, 2940 cm−1, 2358 cm−1, 2197 cm−1, 2136 cm−1, 1725 cm−1, 1100 cm−1 and 1148 cm−1 are flagged to be investigated in further research. ATR-MIR spectroscopy can reduce the time and costs of TP and C* analyses in grape skin extracts.



中文翻译:

ATR-MIR光谱法可预测通过微波辅助或常规热提取方法分别从白色或红色商业品种的葡萄皮混合物中提取的提取物的总酚和颜色

摘要

从在各种条件下生产的480种葡萄皮提取物中收集了衰减的全反射中红外(ATR-MIR)光谱。这些条件是在并行响应表面RS优化实验的不同阶段创建的,旨在通过微波辅助(MAE)或常规热(CTE)方法使红和白葡萄皮提取物中的总酚含量最大化。从在葡萄收获期收集的葡萄制备用于六个白色和六个红色澳大利亚商业品种的皮肤混合物。用Folin-Ciocalteu方法测量单个提取物的总酚含量。光谱采用偏最小二乘(PLS1)回归预测总酚(TP)和颜色(CIELAB色度C*)个别摘录。使用的光谱4000-400厘米全范围进行了检查基于所述原光谱和它们的二阶导数(Savitzky-Golay码,20分)模型-1,以及子范围:4000-1100厘米-1,1500-400厘米- 1,1500年至1100年厘米-1和1457至1168年厘米-1。基于4000-1100 cm -1范围内的二阶导数的PLS1模型为每种肤色提供了TP和C *的最佳结果。总体而言,残留预测偏差(RPD)超过3.0,表明PLS1模型具有公平分类的能力,适合进行筛选。对4000–1100 cm -1的范围进行了比较分析在3840厘米峰:白色和红色皮肤混合物的提取物的光谱之间-1,2940厘米-1,2358厘米-1,2197厘米-1,2136厘米-1,1725厘米-1,1100厘米-1和1148 cm -1标记为有待进一步研究。ATR-MIR光谱仪可以减少葡萄皮提取物中TP和C *分析的时间和成本。

更新日期:2020-01-21
down
wechat
bug