Impact of altered starch functionality on wheat dough microstructure and its elongation behaviour.

The effect of kneading on dough microstructure development, dough elongation and bread volume was investigated using wheat flour with a high mechanical starch modification (MSM) level. The resistance to extension (Rmax) of dough produced from wheat flour with a high MSM level increased by 52.5% because of higher protein network connectivity with prolonged kneading time. The improved network structure was caused by an increased protein branching rate (+14.8%), a decreased protein end-point rate (-24.3%) and a decreased mean lacunarity (-64%). Rmax was highly correlated with specific bread volume (r = 0.97, P < 0.05) only if the dough was not over-kneaded. Kneading time adaptation of the dough produced from high MSM flour significantly increased specific bread volume by 24.4%. Differences compared with the standard can be attributed to weakened network connectivity because of weakened protein interfacial interactions and larger cavities within the gluten network, both caused by starch swelling.