Thermal gelling properties and mechanism of porcine myofibrillar protein containing flaxseed gum at various pH values

Abstract

© 2016 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. Flaxseed gum (FG) was reported to enhance the water holding capacity and thermal stability of myofibrillar protein (MP). However, the role of pH in the interaction of MP and FG is still unclear. The aim of this study was to evaluate gelling properties and physicochemical properties of MP-FG gel at various pH values, to explore the mechanism. The results reveal that higher pH value could increase the water holding capacity of MP-FG gels and the highest gel strength is achieved at pH 6.5. Raman spectroscopic analysis reveals that decreasing the pH from 7.5 to 5.5 induces the partial transformation of α-helices into β-sheets. At the same pH value, addition of FG also leads to the transformation of α-helices into β-sheets, affecting the formation of gel. The storage modulus (G’) values and gelation rates during gelation process gradually declines with the increasing pH, which might be conducted to form a fine dense network.