Dietary fiber variation in ancient and modern wheat species: Einkorn, emmer, spelt and hard red spring wheat

Dietary fiber in wheat is highly variable in whole grain and bran and is strongly dependent on species, variety, milling procedure, and processing. Contradictory information has been reported on the variation of dietary fiber in hulled wheats, and detailed analysis of fiber components is rare. This study was conducted to analyze different dietary fiber fractions of hulled wheat flour and bread. Non-starch polysaccharides such as arabinoxylans and beta-glucans were localized using staining and immunolabelling techniques. The experimental design was separately analyzed randomized complete block designs for einkorn, emmer, and spelt with four field replicates. Imaging dietary fibers revealed the differences in the distribution of non-starch polysaccharides in the kernels depending on the species. Different dietary fiber fractions of flour and bread were analyzed by AOAC 2011.25 integrated dietary fiber assay. Einkorn and spelt wholemeal flour reported significantly (p < .05) lower insoluble dietary fiber and total dietary fiber contents compared to hard red spring wheat. A similar trend was observed for the bread. A few genotypes of einkorn and emmer had a higher content of low molecular weight soluble dietary fibers (SDF-LM). Further research studies are needed to evaluate the health benefits of SDF-LM in these wheat species.