Management Zone Delineation for Winegrape Selective Harvesting Based on Fluorescence-Sensor Mapping of Grape Skin Anthocyanins.

We analyzed the potential of non-destructive optical sensing of grape skin anthocyanins for selective harvesting in precision viticulture. We measured anthocyanins by a hand-held fluorescence optical sensor on a 7 ha Sangiovese vineyard plot in central Italy. Optical indices obtained by the sensor were calibrated for the transformation in units of anthocyanins per berry mass, i.

Prediction models for assessing anthocyanins in grape berries by fluorescence sensors: Dependence on cultivar, site and growing season.

Fluorescence sensors are useful tools for the non-destructive assessment of grape berry anthocyanins. The Multiplex (Mx) sensor here studied provides two anthocyanin indices: ANTH = log(1/Chl-fluorescence_R) and ANTH = log(Chl-fluorescence_R/Chl-fluorescence_G), based on the chlorophyll (Chl) fluorescence excited with red (R) and green (G) light. These indices were calibrated against wet chemistry.

Characterisation of the polyphenol content in the kiwifruit (Actinidia deliciosa) exocarp for the calibration of a fruit-sorting optical sensor.

Introduction: Kiwifruit contains high amounts of anti-oxidants beneficial to health. Its quality is influenced by ripening time, genotype, cultivation techniques, climate and storage conditions after harvest.

Objective: The aim of the present study was to characterise the phenolic content by HPLC methods and to evaluate the performance of a portable optical sensor (Multiplex 3), for in vivo non-destructive phenolic compound assessment in kiwifruits.