jf6b01999_si_001.pdf (835.83 kB)
Use of Visible and Short-Wave Near-Infrared Hyperspectral Imaging To Fingerprint Anthocyanins in Intact Grape Berries
journal contribution
posted on 2016-09-22, 00:00 authored by Maria P. Diago, Juan Fernández-Novales, Armando M. Fernandes, Pedro Melo-Pinto, Javier TardaguilaIn
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 (R2CV) 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 (R2P) 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.