Main Article Content
Grape juice is considered as an important agricultural raw material for food processing industry and fresh juice consumption . This research thereby aimed to evaluate grape juice’s total soluble solids (TSS) and titratable acidity (TA) using near infrared spectroscopy. One hundred freshly squeezed grape juice samples (calibration: 60, validation: 40) were measured their absorbance in wavelength ranges of 800-1090 nm using transmittance technique. Chemometrics of partial least squares regression (PLSR) was thereafter performed in order to develop calibration models for both quality parameters. Prediction results indicated high value of coefficient of determination (R2pre), expressing high relationship between predicted and actual values for both TSS and TA; 0.972 and 0.898, respectively. The prediction models also provided low value of standard error of prediction (SEP), which were 0.46 and 0.10 %, respectively. In this study , near infrared spectroscopy was proofed to be a promising technique for evaluating grape juice quality.
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