Optimization of Informative Spectral Variables for the Quantification of EGCG in Green Tea Using Fourier Transform Near-Infrared (FT-NIR) Spectroscopy and Multivariate Calibration

Abstract

Epigallocatechin-3-gallate (EGCG) is credited with the majority of the health benefits associated with green tea consumption. It has a high economic and medicinal value. The feasibility of using different variable selection approaches in Fourier transform near-infrared (FT-NIR) spectroscopy for a rapid and conclusive quantitative determination of EGCG in green tea was investigated. Graphically oriented multivariate calibration modeling procedures such as interval partial least squares (iPLS), synergy interval partial least squares (siPLS), and genetic algorithm optimization combined with siPLS (siPLS-GA) were applied to select the most efficient spectral variables that provided the lowest prediction error. The performance of the final model was evaluated according to the root mean square error of prediction (RMSEP) and coefficient of determination (R(2)) for the prediction set. Experimental results showed that the siPLS-GA model obtained the best results in comparison to other models. The optimal models were achieved with R(2)(p) = 0.97 and RMSEP = 0.32. The model can be obtained with only 36 variables retained and it provides a robust model with good estimation accuracy. This demonstrates the potential of NIR spectroscopy with multivariate calibration methods to quickly detect the bioactive component in green tea.

Impact of thearubigins on the estimation of total dietary flavonoids in the European Prospective Investigation into Cancer and Nutrition (EPIC) study

“…The non-specific spectrophotometric method used to date 9 only provides a crude estimation of the TR concentrations in teas. Fourier transform infrared spectroscopy 17 and pyrolysis-gas chromatography-mass spectrometry 18 are potential methods to analyze high-molecular weight polyphenols, although they need to be further explored to estimate TR in tea.…”

Infrared Spectroscopy as a Versatile Analytical Tool for the Quantitative Determination of Antioxidants in Agricultural Products, Foods and Plants

“…Epigallocatechin-3-gallate (EGCG) is credited with the majority of the health benefits associated with green tea consumption and has a high economic and medicinal value [ 60 ]. The feasibility of using different variable selection approaches in FT-NIR spectroscopy for the quantitative determination of EGCG in green tea was investigated [ 60 ].…”

“…Epigallocatechin-3-gallate (EGCG) is credited with the majority of the health benefits associated with green tea consumption and has a high economic and medicinal value [ 60 ]. The feasibility of using different variable selection approaches in FT-NIR spectroscopy for the quantitative determination of EGCG in green tea was investigated [ 60 ]. The calibration methods reported by the authors included interval partial least squares (iPLS), SiPLS, and genetic algorithm (GA) optimization combined with SiPLS (SiPLS-GA) were applied to select the most efficient spectral variables that provided the lowest prediction error [ 60 ].…”

“…The feasibility of using different variable selection approaches in FT-NIR spectroscopy for the quantitative determination of EGCG in green tea was investigated [ 60 ]. The calibration methods reported by the authors included interval partial least squares (iPLS), SiPLS, and genetic algorithm (GA) optimization combined with SiPLS (SiPLS-GA) were applied to select the most efficient spectral variables that provided the lowest prediction error [ 60 ]. The performance of the final model was evaluated according to the RMSEP and R 2 for the prediction set [ 60 ].…”

The Quality Control of Tea by Near-Infrared Reflectance (NIR) Spectroscopy and Chemometrics

“…NIR spectroscopy has been successfully used for the prediction of major compositions contents in tea in recent years. Nonetheless, only one or several components were simultaneously measured by NIR spectroscopy in previous studies [55,56]. Lee et al firstly determined the contents of nine individual catechins and caffeine by NIR spectroscopy.…”