Supplementation of wheat flour products with wheat bran dietary fiber: Purpose, mechanisms, and challenges

The emergence of chronic diseases has increased interest in foods with high nutritional value and health benefits. In particular, high-fiber food is becoming more popular. However, current milling processes extract the grain cortex, which contains most of the dietary fiber. This results in commercial available flour that contains mainly of starch and protein, but is lacking in dietary fiber. The direct addition of purified dietary fiber from wheat bran to processed flour results in enriched flour with improved nutritional properties without the issues of high enzymatic activity, high lipid content, and short shelf life associated with whole wheat flour. This review discusses the supplementation of supplementing flour products with wheat bran dietary fiber (WBDF) and how WBDF affects the quality of flour products by influencing dough components, especially protein. Challenges of WBDF supplementation in flour products are discussed and solutions are proposed. WBDF-enriched flour has a longer shelf life than whole wheat flour. WBDF can weaken the gluten network structure and change the secondary structure of glutenin to change the gluten network strength and protein properties of the dough. This is due to changes in the physical structure and chemical bonds of WBDF and gluten. Understanding effects of WBDF on gluten protein should guide the development and production of improved flour products. Overall, using modified WBDF can expand the application range and improve the market appeal of WBDF-rich flour products.