Underlying mechanism governing the influence of peanut oil addition on wheat dough viscoelasticity and Chinese steamed bread quality
Tingjing Zhang, Erqi Guan, Yuling Yang, Lili Zhang, Yuanxiao Liu, Ke Bian
Abstract
In this work, how the added Peanut oil (PO) influenced dough characteristics was in depth revealed by dynamic oscillatory test, bread quality determination, gluten properties evaluation, lipids distribution, size exclusion chromatography, matrix-assisted laser desorption ionization-time of flight mass spectrometry, free sulfhydryl and disulfide bonds analysis, electrophoresis, and Fourier transform infrared spectroscopy, which showed the PO addition from 2.0% to 4.0% (Flour weight base) facilitated dough viscoelasticity and steamed bread quality, especially with 3.0% PO displaying the most improved effects. The trapped PO in gluten preferentially interacted with SDS-soluble gluten through hydrophobic and hydrogen bonds and weak electrostatic interactions, resulting in medium glutenin aggregation via dityrosine and disulfide bonds. The extra PO interacted with non-gluten proteins and made globulin retain in gluten network. The retained globulin was then cross-linked with SDS-soluble gluten through non-covalent interactions, weakening disulfide bonds and causing depolymerization of the formed medium glutenin polymers in some degree. This behavior conferred related dough with a moderate protein aggregation which combined with the retained globulin itself contributed to ameliorated dough qualities.