Potential of fluorescence spectroscopy in detection of low-levels of gluten in flour: A preliminary study

Celiac disease is caused due to the ingestion of gluten containing food products. Eating gluten free diet is only way to avoid its occurrence. Gluten free products may get contaminated during the handling and processing operation which leads to the adverse impact on the gluten intolerant patients. Three different gluten free mixes were adulterated with two different types of wheat flours to get the gluten concentration in the range of 0-5 % by making 94 sample combinations. The obtained fluorescence spectra from these samples were transformed using multiplicative scatter correction (MSC) pre-processing to develop partial least square regression (PLSR) model for the prediction of low-levels of gluten. The obtained results showed a high value of 0.90 correlation coefficient (R-2) with 0.46 % root mean square error of cross validation (RMSECV). The calibration and prediction models also showed the same R2 with root mean square error of calibration (RMSEC) and prediction (RMSEP) of 0.41 % and 0.46 % respectively. Hence fluorescence spectroscopy can be used to estimate the level of adulteration which is helpful for developing a sensor for determination of low-levels of gluten as a rapid and non-invasive method in food applications. (C) 2016 Elsevier Ltd. All rights reserved.