[Visible transmittance techniques for rapid analysis of sugar content of fresh navel orange juices]

The feasibility of visible spectroscopic technology for rapid quantifying sugar content (SC) of navel orange fresh juices was investigated by means of spectral transmittance technique. A total of 55 juice samples were used to develop the calibration and prediction models. Calibration models based on different spectral ranges and different spectral pretreatment were compared in the precent research. Performance of different models was investigated in terms of root mean square errors of prediction (RMSEP) and correlation coefficient (r) of validation set of samples. The correlation coefficient of calibration model for SC was 0.965, the correlation coefficient of prediction model for SC was 0.857, and the corresponding RMSEP was 0.562. The results show that visible transmittance technique is a feasible method for non-invasive estimation of fruit juice SC.