Heat-induced Gelation of a Mixture of Myofibrillar Protein and Succinylated Soy llS Protein

Abstract

Mixture of natural actomyosin and succinylated soy l1S protein were heated at 70°C for 30min, and thermally induced gelation properties were tested by measuring physical properties and observing micro-structure. Succinylation up to 50% of amino groups of soyllS proteins, 10-60mg/ml increased the heat-induced turbidity with increasing protein concentration. However, the ratio of protein remaind after centrifugation was less affected by the difference of protein concentration. Succinylation up to 50% increased the heatinduced gelation of the mixd two proteins with increasing protein concentration, while physical properties of native (unmodified) protein systems showed the highest values at 30mg/ml protein concentration. Values of elastic modulus and modulus of breaking elasticity of succinylated protein systems were higher at more than 30mg/ml protein concentration, and value and of breaking energy of the systems were higher at the range of all protein concentration compared with native proteins. It was suggested that these changes of physical properties were caused by micro-structural changes of gels, especially the difference in porocity of respective gel networks.