Reduction of rutin loss in buckwheat noodles and their physicochemical characterisation

Tartary buckwheat was subjected to hydrothermal treatments for minimising rutin loss in buckwheat-based foods by water addition. When native buckwheat flour was mixed with water for 60 min, the rutin content was distinctly reduced from 3.74 g/100 g to 0.31 g/100 g, increasing the amount of quercetin. However, the rutin content remained constant and quercetin was hardly detected in hydrothermally-treated buckwheat flour. Also, when noodles were prepared with wheat and buckwheat flours (7:3, w/w), the noodle samples containing hydrothermally-treated buckwheat flour, showed higher amounts of rutin (more than 0.83 g/100 g) than the control noodle with native buckwheat flour (0.27 g/100 g). In addition, the use of hydrothermally-treated buckwheat flour gave less pasting parameters and lower viscoelastic properties. The noodle dough with hydrothermally-treated buckwheat flour also had greater water absorption and development time during mixing while the elongation stress of the noodle dough was reduced.