Effect of Flaxseed Flour on Rheological Properties of Wheat Flour Dough and on Bread Characteristics

Flaxseed (Linum usitatissimum) is an oilseed that is high in omega-3 fatty acid, dietary fiber and lignan. These components are responsible for the health promoting effects of flaxseed. Incorporating flaxseed into foodstuffs such as bread is an approach to increase dietary flaxseed. However, the need for a rapid screen method is needed since a complete baking process may take several hours. Correlating Farinograph parameters with bread characteristics may result in a rapid test that would allow for researchers to identify the proper levels of flaxseed addition to bread without a lengthy baking procedure. Therefore, the effect of 0, 6, 10, and 15% (wt/wt) flaxseed flour (FF) on Farinograph rheological properties of bread flour dough and on bread characteristics were investigated. Results showed that FF significantly (p< 0.05) increased dough water absorption, peak time, and mixing tolerance index, but decreased dough stability. Oven spring was significantly lower for all flaxseed treatments compared to the control. However, the loaf volume of bread made with 6 and 10% FF did not differ significantly (p < 0.05) from the control. The FF concentrations tested did not affect the specific volume of the bread even though the water absorption values were higher for doughs with FF. The breads containing flaxseed had darker crust color and a more yellow crumb color compared to control bread, but the crumb structure was not negatively impacted. Results indicated that Farinograph parameters of bread flour dough could be used as a method for screening FF addition to bread.