Sugar Analysis in Apple Juice by FTIR Spectroscopy with PLS Regression

Fourier Transform mid-Infrared Spectroscopy (FT-MIR) shared with multivariate statistics was applied for the quantitative analysis of total sugar in 9 processed commercial fruit juices. PLSR (Partial least-squares regression) was used to generate calibration models that were cross-validated. As an analytical technique, the suitability of FTIR in mid-range (4000-1cm-4001cm) is investigates in this work. For calibrations of the sugar content in apple juice, matrix methods are used, in the range defined for apple juice in juice industry. Refractometer is used as a reference technique, which provides the validation of the FTIR results. FTIR is used for analyzing the results obtained from reference method in this word, as a non-destructive and fast technique.