The prediction of ripening parameters in Primitivo wine grape cultivar using a portable NIR device

A portable NIR device, the SCiO™ molecular sensor (Consumer Physics Inc., Israel) operating in the range 740–1070 nm, was used to determine some ripening parameters, namely total soluble solids (TSS), titratable acidity (TA), and pH, of Primitivo wine grape cultivar. Data of Primitivo berries trained to Guyot (unilateral) and bush-vine (named in Italy as ‘Alberello’), were collected in the vineyard with the device and compared with laboratory analysis during the 2019 and 2020 seasons. The calibration models provided similar results for both Guyot and Alberello; the TSS model with R² = 0.97, RMSE = 1.33, and RPD = 5.76 for Guyot and with R² = 0.97, RMSE = 1.41, and RPD = 5.31 for Alberello were the best models. Finally, the calibrated models were validated on a different dataset showing that the device is eligible for non-destructive assessments of ripening parameters of wine grape cultivars. The best results were obtained for the TSS model validation with R² = 0.95; RMSE = 1.86, RPD = 4.07 for Guyot and R² = 0.92, RMSE = 2.53, RPD = 3.17 for Alberello.