A jumbo squid (Dosidicus gigas) protein concentrate obtained by alkaline dissolution and its conformational changes evaluation

Abstract

Jumbo squid (Dosidicus gigas) is an important fishery resource in Mexico. It is abundant, but with little or nothing added value, therefore is necessary to search alternatives of processing. Due to its muscle characteristics, the aim of this study was to obtain protein concentrates by means of alkaline-aided solubilization followed by isoelectric protein precipitation. A protein concentrate (PC) was obtained from jumbo squid, and then compared with unwashed mantle mince (M). Surface hydrophobicity of PC was lower than M. Zeta potential showed a major potential of aggregation for PC. The total and reactive sulfhydryls groups were higher in M, while in sol-gel transition a reduction of total sulfhydryl groups was noticed. Thermogravimetric analysis revealed that PC loses water more easily that M, while the rheological evaluation showed that M formed a more elastic gel. The gelling properties of PC and M are governed by the physicochemical properties of proteins, which are affected by processing conditions.