On-line discrimination of storage shelf-life and prediction of post-harvest quality for strawberry fruit by visible and near infrared spectroscopy

Quick assessment of storage time is important for the guarantee of fruit shelf-life. On-line discrimination of refrigerated storage time and prediction of post-harvest quality for strawberry fruit was carried out by visible and near-infrared (Vis/NIR) spectroscopy. For the classification of samples with storage time of 1, 3, 5, and 7 days, partial least square discriminant analysis (PLS-DA) achieved correct classified rates of 93.3-97.4% in prediction based on selected wavelengths obtained by competitive adaptive reweighted sampling (CARS) at speeds of 0.05, 0.10, and 0.15 m/s. Moreover, for prediction of soluble solids content (SSC) in strawberry, the determination coefficient (r(p)(2)), root mean square error of prediction (RMSEP), and RPD value obtained by PLS coped with CARS at fruit moving speed of 0.10 m/s was 0.733, 0.699 degrees Brix and 1.96, respectively. Overall, this study indicates that Vis-NIR spectroscopy offers the potential as an on-line tool for quality assurance of strawberry fruit. Practical applications Visible and near-infrared (Vis/NIR) spectroscopy is a very attractive technique for nondestructive evaluation of quality of food products. Strawberry has an extremely short shelf-life which is estimated to be less than 5 days. Rapid identification its postharvest storage time is essential for the evaluation of its shelf-life. Based on the results reported here, Vis-NIR has the potential for on-line monitoring of postharvest storage time and post-harvest quality for strawberry fruit in real situation.