Combining bran-enrichment with sugar replacement in biscuits enables the flexible use of a sustainable and fibre-rich by-product

Fibre-rich by-products like wheat bran are a sustainable source of health promoting components. However, substantial enrichment in bran of popular and convenient food like biscuits negatively impacts dough rheology and baked product properties. In this study, we suggest that alterations in dough rheology and biscuit properties resulting from bran enrichment can be compensated for by steering the properties of the water-sugar mixture as obtained by concomitant sugar replacement. In particular, the plasticizing properties of the water-sugar mixtures and the hygroscopicity of the sugar mixture were used as quantitative parameters in combination with the ratio between bran and flour. These three parameters were varied independently and tested against dough rheology (amplitude sweep tests and dynamic mechanical thermal analysis) and biscuit properties. The results indicated that the three parameters could well describe all the relevant physical properties related to dough rheology after mixing and during heating and to biscuit properties. The increase in dough elastic behavior induced by bran addition could be compensated for by reducing the plasticizing and hygroscopic properties of the sugar (replacers) mixture. Increased mechanical strength and reduced biscuit spread of bran enriched biscuits could be compensated in a similar manner. Overall, the formulation strategy presented in this study suggests the possibility to decouple texture from nutritional composition of bakery products like biscuits, allowing a more flexible use of fibre-rich and nutrient-dense by-products like bran.