Weichun Pan
Zhejiang Gognshang University School of Food and Biotechnology, PRC
Title: Salting-in effect on muscle protein extracted from the giant squid (Dosidicusgigas)
Biography
Biography: Weichun Pan
Abstract
The salting-in effect of muscle protein is a well-known phenomenon in food science but is hard to explain by conventional theories. Myofibrillar protein extracted from the giant squid (Dosidicusgigas) was selected as a model muscle protein to study this mechanism in potassium chloride (KCl) solutions. Studies have reported changes in the secondary structures of myofibrillar protein molecules caused by concentrated salt, particularly in the conformation of the paramyosin molecule. Zeta-potential determinations showed that these secondary structures have modified protein molecule surfaces. As salt concentration increased from 0.1 to 0.5M, the zeta-potential of the myofibrillar protein molecules fell from −7.24±0.82 to −9.99±1.65 mV. Meanwhile, the corresponding second virial coefficient increased from –85.43±3.8×10-7 to –3.45±1.3 × 10-7 mol mL g-2. Based on the extended law of corresponding states, the reducing attractive interactions cause protein solubility to rise. Determining the solubility in alternating KCl concentrations also demonstrated that this conformational change was reversible.