Document Type : Research Paper

Abstract

Flaxseed is rich in omega-3 essential fatty acids, lignans, dietary fiber and natural antioxidants such as tocopherols. Because of its functional effect in preventing disease, flaxseed is used as an ingredient to fortify food formulations. Bread is a major food product in Iran. Fortification of wheat flour with ground flaxseed makes use of the healthy benefits of flaxseed. This study investigated the rheological properties of dough prepared using flaxseed-supplemented flour. Flaxseed flour was used to replace 50, 10, 150 and 200 g.kg-¹ of the wheat flour. Farinograph results showed greater water absorption, longer development time, increased softening and a higher farinograph quality number for the flaxseed-supplemented flours over the control flour. Dough stability time for all blends decreased except for that with 5% flaxseed. Extensograph testing revealed a significant increase in maximum resistance of dough to extension and a substantial decrease in dough extensibility and extension energy. Despite the beneficial health effects of flaxseed in fortification of bread, the negative effects of high concentrations of flaxseed powder on dough quality and rheological properties must be considered and precautions taken to compensate for these adverse effects.

Keywords

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