Abstract
The potential of visible-near infrared (vis/NIR) spectroscopy (400 nm to 1100 nm) for classification of grape berries on the basis of multi inner quality parameters was investigated. Stored Vitis vinifera L. cv. Manicure Finger and Vitis vinifera L. cv. Ugni Blanc grape berries were separated into three classes based on the distribution of total soluble solid content (SSC) and total phenolic compounds (TP). Partial least squares regression (PLS) was applied to predict the quality parameters, including color space CIELAB, SSC, and TP. The prediction results showed that the vis/NIR spectrum correlated with the SSC and TP present in the intact grape berries with determination coefficient of prediction (RP2) in the range of 0.735 to 0.823. Next, the vis/NIR spectrum was used to distinguish between berries with different SSC and TP concentrations using partial least squares discrimination analysis (PLS-DA) with >77% accuracy. This study provides a method to identify stored grape quality classes based on the spectroscopy and distributions of multiple inner quality parameters.
Highlights
Grapes are berry fruits with thin peels and high moisture and sugar content, and are more sensitive to storage and transportation conditions than other types of fruits
For stored Manicure Finger berries, the L*, a*, and b* values were in the range of 34.82 to 49.50, 2.07 to 11.03, and 2.80 to 15.43, respectively; the average L*, a*, and b* values were 42.26, 5.94, and 9.41, respectively
We proposed a method of grading grape berries using visible-near infrared (vis/near infrared (NIR)) spectra, which can define the quality classes of grape berries based on the distributions of inner quality parameters such as soluble solid content (SSC) and total phenolic compounds (TP)
Summary
Grapes are berry fruits with thin peels and high moisture and sugar content, and are more sensitive to storage and transportation conditions than other types of fruits. As photosynthesis is halted after fruit harvest, respiration becomes the main metabolic process during storage and transportation. This catabolism results in the consumption of organic matter in fruit, affecting the edible quality and nutritional value of post-harvest grapes and considerably reducing their commodity value. Studies on evaluation of grape berry quality during cold storage are limited. Improving the cold storage resistance of grapes is an important aspect of postharvest preservation of grape fruit, while the non-destructive monitoring of grape quality during storage and the rapid determination of the freshness of grapes are new points to be considered for effective and rational arrangement of the stock and reduction in storage loss after harvest [2]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
