Investigating the Applicability of a Snapshot Computed Tomography Imaging Spectrometer for the Prediction of Brix and pH of Grapes

TL;DR

This study evaluates a cost-effective, portable CTIS hyperspectral imaging system for predicting grape Brix and pH, demonstrating its comparable accuracy to traditional systems and its potential for in-field grape quality assessment.

Contribution

It introduces the application of a snapshot CTIS hyperspectral system for grape quality prediction, highlighting its advantages over traditional line scan systems.

Findings

CTIS spectra correlate well with reference measurements

CTIS system offers lower cost and portability

Potential for in-field grape quality assessment

Abstract

In this paper, a recently developed snapshot hyperspectral imaging (HSI) system based on Computed Tomography Imaging Spectroscopy (CTIS) is utilized to determine Brix and pH values in Sheegene 20 table grapes through Partial Least Squares Regression (PLSR) modeling. The performance of the CTIS system is compared with that of a state-of-the-art line scan HSI system by imaging 100 grapes across both platforms. Reference measurements of Brix and pH values are obtained directly using a refractometer and a pH meter, as these parameters are essential for assessing the quality of table and wine grapes. The findings indicate that the spectra captured by the CTIS camera correlate well with the reference measurements, despite the system's narrower spectral range. The CTIS camera's advantages, including its lower cost, portability, and reduced susceptibility to motion errors, highlight its potential for promising in-field applications in grape quality assessment.