The paper deals with methodological approaches to study the rheological properties of gelatin gels based on the thorny skate cartilage broth ( Raja radiate ), which is an aqueous extract of chondroitin sulfate, depending on the manufacturing technology. It is shown that the use of modern instrumental methods for studying the rheological properties of gels and methodological approaches typical of physical and colloidal chemistry allows to obtain the most complete and objective information about the mechanisms of formation of key consumer properties of fish products and the main directions of improving the technology of its manufacture. The influence of gelatin concentration in the range from 0.5 to 5.0 % in chondroitin sulfate-containing broths from the thorny skate cartilage on kinematic and dynamic viscosity of broths, as well as on the strength, melting point and shear stress indices of gels based on these broths was studied. As control samples, aqueous solutions of gelatin in concentrations from 0.5 to 5.0 % and gels based on them were used in the studies. The analysis of the results of the study showed that the broths prepared on the basis of the thorny skate cartilage have increased relative to the control samples the values of kinematic and dynamic viscosity, the increase in indicators is characterized by a directly proportional dependence on the concentration of gelatin in the broth. Gelatin gels based on chondroitin sulfate-containing broths made from the thorny skate cartilage have increased strength, which has a positive effect on the organoleptic evaluation and consumer properties of the finished culinary products.
Rheological properties of gelatin gels filled with phospholipids vesicles. Dynamic and uniaxial compression measurements