Controlling dough rheology and structural characteristics of chickpea-wheat composite flour-based noodles with different levels of Artemisia sphaerocephala Krasch. gum addition

Abstract

The effect of Artemisia sphaerocephala Krasch. gum (ASKG) addition on the dough performance and structural characteristics of the wheat-chickpea composite flour-based product was studied. The low levels of ASKG addition (0.03-0.5%) tended to cause a remarkable increase in the viscoelastic properties of the composite dough system, followed by a decreased trend at higher level of gum addition (0.8%). This trend was in agreement with the variations found for cooking loss, free -SH content, and relative crystallinity measured by X-ray diffractometer for dough samples. The confocal laser scanning micrographs (CLSM) further confirmed the above trend. For cooked noodle samples, the variations in pasting properties was supported by the changes in relatively crystallinity and free sulfhydryl content, suggesting a relatively more compact structure was formed at the 0.3% of gum addition. The scanning electron microscopic and CLSM observations both revealed that a relatively denser and more coherent network structure was achieved at 0.3% ASKG addition. On the other hand, the higher levels of gum substitution at 0.5% and 0.8% tended to disrupt this stronger network with visible signs of starch deformation, due to the inefficient entrapment of starch molecules during cooking as a result of the lack of gluten network.

Keywords: Artemisia sphaerocephala Krasch. gum; Confocal laser scanning microstructure; Dough rheology; Structural characteristics; Wheat-chickpea flour-based noodle.