The rheological properties of differentially extracted polysaccharides from potatoes peels

The effects of concentration, temperature, pH, and salt ion concentration on the apparent viscosity of potato peel (PP) polysaccharide solutions were studied. The results showed that the PP polysaccharides exhibited the characteristics of "non-Newtonian fluid". The apparent viscosity of the PP polysaccharides decreased under acidic, alkaline conditions, and with the increasing temperature. At the increasing concentration of PAC with the addition of four ion concentrations, the apparent viscosity was decreased gradually. The apparent viscosity of PAL increased with four ion concentrations, while that of PW increased initially with the rising concentration of Na⁺, Mg²⁺, and K⁺ and then decreased. Addition of Ca²⁺ lowered the apparent viscosity initially which was followed by further increase. The results of dynamic rheological experiment showed that the loss modulus G″ of PP polysaccharide was higher than the storage modulus G' at lower frequencies, and vice versa at higher frequencies. With the increasing concentration of PP polysaccharides, the values of the intersection of G' and G″ were lowered. The results showed that the rheological properties of PP polysaccharide solutions were affected by concentration, temperature, pH, and salt ions.