RT Journal Article
SR Electronic
T1 Indirect Evaluation of Microbial Spoiling Activity in Grape Marcs by Near-Infrared Spectroscopy
JF American Journal of Enology and Viticulture
JO Am. J. Enol. Vitic.
FD American Society for Enology and Viticulture
SP 411
OP 415
DO 10.5344/ajev.2013.12133
VO 64
IS 3
A1 Barbara Bovo
A1 Massimo De Marchi
A1 Milena Carlot
A1 Stefano Soligo
A1 Viviana Corich
A1 Alessio Giacomini
YR 2013
UL http://www.ajevonline.org/content/64/3/411.abstract
AB Ethanol, reducing sugars, and acetic acid content, related to yeast and bacteria spoiling activities, were chosen as indicators of technological suitability for grape marc devoted to the production of grappa. A fiber-optic probe was placed in contact with marc using visible near-infrared spectroscopy (NIRS) spectral range from 350 to 1800 nm. Analytical determination of sugar, ethanol, and acetic acid concentration followed standard laboratory methods and partial least squares regressions were performed using untreated and pretreated spectra data. Models were validated using full cross-validation, and their predictive ability was determined by coefficient of determination of cross-calibration and standard error of cross-validation. The best prediction models were developed using absorbance spectra for ethanol and for sugar content, and a medium predictive ability of NIRS was obtained for acetic acid. Results show that NIRS can be used for rapid quality assessment of grape marcs upon arrival at the distillery, in view of their potential technological transformation.