Prediction of pelargonidin-3-glucoside in strawberries according to the postharvest distribution period of two ripening stages using VIS-NIR and SWIR hyperspectral imaging technology

Abstract

The quality characteristics and consumer acceptability of strawberries depend on their ripening stages. Pelargodinin-3-glucoside (P3G) is the main anthocyanin in strawberries and changes during postharvest distribution. Hyperspectral imaging technology (HSI), which covers the ranges of visible-near infrared (VIS-NIR) and shortwave infrared (SWIR) light, was used to predict the P3G of strawberries for two types of harvest maturity, half maturity (HM) and full maturity (FM) during distribution periods. Spectral data was extracted from hyperspectral images of strawberries at the two stages of maturity and partial least square (PLS) regression was used to develop the prediction model of P3G. The highest prediction accuracy was 86% in HM using the SWIR region. Meaningful wavelengths to develop the PLS model were approximately 970, 1,153, 1,303, and 1,445 nm for moisture, carbohydrates, and anthocyanin. Moreover, the spatial information of P3G accumulation can be also analyzed using HSI. The overall results indicated that HSI could be used for the prediction of P3G with different harvest maturity of strawberry. Additionally, this technology could provide the information of distribution periods of strawberry by monitoring changes of pigment of strawberries.