Study on the variation of stable isotopic fingerprints of wheat kernel along with milling processing

In the present study, the variation of stable isotopic ratio of carbon and nitrogen in wheat kernel along with milling fractions (bran, germ, break flour, reduction flour) in three genotypes from three different locations in five years (2012-2016) was investigated. Isotope ratio mass spectrometry (IRMS) was used to analyze the samples. Analysis of variance revealed significant differences among regions, genotypes, years, and their interactions for all wheat fractions. Region showed the largest variability in the δ13C and δ15N values of wholemeal and different fractions. A Significant positive correlation was found between whole kernel and different milling fractions for both carbon and nitrogen isotopes suggesting reliability of fractions fingerprints for geographical traceability of wheat. Moreover, a classification model based on the canonical discriminant analysis (CDA) was built which correctly classify 93.8% samples in all regions using light stable carbon and nitrogen isotope of whole wheat and milling fractions. Present findings significantly contribute to understand the variations of isotopic composition in different wheat milling fractions depending on geographical origins and offer valuable insight into the control of mislabeling regarding geographical origin.