Quality Assessment of Red Wine Grapes through NIR Spectroscopy

Red wine grapes require a constant follow-up through analytical chemistry to assure the greatest quality. Wet chemical procedures are time-consuming and produce residues that hard eliminate. NIR (near infrared radiation) spectroscopy has been referred as an accurate, rapid, cost-efficient technique evaluate quality in many fruit species, both field industry. The main objective of this study was develop predictive models using quantify important attributes grapes. Soluble solids content (SSC), titratable acidity (TA), total phenolic content, flavonoids, anthocyanins, tannins were quantified four red grape varieties, ‘Aragonês’, ‘Trincadeira’, ‘Touriga Nacional’, ‘Syrah’. Samples collected during 2017 2018 along véraison. Prediction developed near-infrared portable device (Brimrose, Luminar 5030), spectra from entire under near conditions. Models built partial least square regression (PLSR) algorithm SSC, TA, exhibited determination coefficient 0.89, 0.90, 0.87, 0.88, respectively. Residual Deviation (RPD) values these higher than 2.3. prediction for have considerable potential Total flavonoids predicted with slightly lower capacity, R2 = 0.72 0.71, respectively, RPD 1.6, indicating very low borderline quantitative predictions phenols models.