Functional characterisation of muscle and skin collagenous material from hake (Merluccius merluccius L.)

The purpose of this paper was to examine the modifications occurring in certain functional hydration properties (protein solubility in 0.5 M acetic acid, apparent viscosity and water-binding capacity) of the collagenous material from skin and muscle of hake (Merluccius merluccius L.) in relation to the pH and the ionic strength (expressed as variation in NaCl concentration) of the medium. At the same time, these modifications were compared with those reported for collagenous material from trout in a previous paper. Generally speaking, skin collagenous material showed higher functionality than muscle collagenous material. It was found that protein solubility, apparent viscosity and water-binding capacity presented maximum values at pH levels between 2 and 4, and at concentrations of less than 0.25 M NaCl. Finally, the functional values were found to be higher in collagenous material from hake than from trout, especially in the skin material. ©