Effects of dough mixing time before adding konjac glucomannan on the quality of noodles

In this study, effects of 5% konjac glucomannan (KGM) blended with low-protein flour at different dough mixing duration on the properties of dough and noodles were investigated. To prepare the KGM noodle samples, 5% KGM was added after low-protein flour mixed with water for 0, 2 and 4 min, respectively. The three samples above were defined as T₀ KGM, T₂ KGM and T₄ KGM noodle samples, respectively. The results revealed that the elastic modulus (G') and viscous modulus (G″) of dough both increased with extending dough mixing time before adding KGM. T₄ KGM samples showed the least cooking loss. Textural properties including hardness, cohesiveness and tensile strength of KGM noodles had a tendency to increase with a longer dough mixing time before adding KGM. Microstructure of dough and noodles confirmed that a longer dough mixing time before adding KGM made microstructure more compact with a thickened gluten matrix. The sensory quality of the T₂ KGM and T₄ KGM samples was better than that of the T₀ KGM samples.