Carotenoid determination in tomato juice using near infrared spectroscopy**

Abstract

A rapid non-destructive method for profiling tomato carotenoids was developed using NIR spectrometry. One hundred and twenty tomato samples were produced at the Experimental Farm of Szent István University in Gödöllo (Hungary). The sample preparation was based on homogenization. The mixed samples were scanned with a diode array Perten DA7200 NIR Analyzer (950-1650 nm) and analyzed by high performance liquid chromatography. The calibration was based on partial least squares regression with cross-validation. The performance of the final model was evaluated according to root mean square error of cross-validation. The results indicate that the main carotenoid components were accurately predicted. The correlation between the NIR measurement and the β-carotene content of tomatoes was adequately high [R[2]CV = 0.89; root mean square error of cross-validation = 0.174 μg g[-1]]. The NIR method was also performed for the determination of the all-trans lycopene content (R[2]CV = 0.75; root mean square error of cross-validation = 6.88 μg g[-1]). It can be concluded that the diode array NIR spectrometer has the potential to be used for the determination of the main carotenoids of tomatoes.