title: Feasibility of using a miniature NIR spectrometer to measure volumic mass during alcoholic fermentation.
abstract: Volumic mass-a key component of must quality control tests during alcoholic fermentation-is of great interest to the winemaking industry. Transmitance near-infrared (NIR) spectra of 124 must samples over the range of 200-1,100-nm were obtained using a miniature spectrometer. The performance of this instrument to predict volumic mass was evaluated using partial least squares (PLS) regression and multiple linear regression (MLR). The validation statistics coefficient of determination (r(2)) and the standard error of prediction (SEP) were r(2) = 0.98, n = 31 and r(2) = 0.96, n = 31, and SEP = 5.85 and 7.49 g/dm(3) for PLS and MLR equations developed to fit reference data for volumic mass and spectral data. Comparison of results from MLR and PLS demonstrates that a MLR model with six significant wavelengths (P < 0.05) fit volumic mass data to transmittance (1/T) data slightly worse than a more sophisticated PLS model using the full scanning range. The results suggest that NIR spectroscopy is a suitable technique for predicting volumic mass during alcoholic fermentation, and that a low-cost NIR instrument can be used for this purpose.
authors.affiliation: Centro de Investigación y Formación Agraria de Cabra-Priego, Instituto Andaluz de Investigación y Formación Agraria, Pesquera, Alimentaria y de la Producción Ecológica, Consejería de Agricultura y Pesca, Junta de Andalucía, Cabra (Córdoba), Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Fernández-Novales
authors.forename: María-Isabel
authors.initials: MI
authors.lastname: López
authors.forename: Virginia
authors.initials: V
authors.lastname: González-Caballero
authors.forename: Pilar
authors.initials: P
authors.lastname: Ramírez
authors.forename: María-Teresa
authors.initials: MT
authors.lastname: Sánchez
mesh_terms: D000431:Ethanol / Q000378:metabolism*; D005240:Feasibility Studies; D005285:Fermentation; D016018:Least-Squares Analysis; D016014:Linear Models; D011786:Quality Control; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation / Q000379:methods*; D014920:Wine
chemical_list: D000431:Ethanol