Establishment of nondestructive testing model of the protein content in wheat flour by near infrared spectroscopy

The 107 samples of wheat flour were scanned directly by NIRS and their protein contents were measured by Joe Dumars combustion method. The protein content model was built up using near infrared spectroscopy (NIRS) and the FOSS system as the analyzer. The influences on the model of factors, such as the mathematics methods and optics treatment methods were studied. Experimental results indicated that the optimal model was built by using the Modified partial least square (MPLS) under none scattering approach and two rank differential coefficient derivative preprocessing method, its standard deviation of cross validation (SECV) was 0.4112%, fore cast standard deviation(SEP) was 0.492%, predicted RSQ was 0.937. To sum up, the NIRS technique can realize fast detection of flour protein content and provide technical support for food regulator when they are monitoring the flour market.