SUNFLOWER SEED TOTAL PROTEINS - EFFECT OF DRY AND WET HEATING

Proteins in sunflower seeds, heat treated (dry and autoclaved), show c hanges in physicochemical properties. Changes include the ultraviolet absorption spectrum, specifically at 324 nm due to bound chlorogenic a cid. Wet heating under steam pressure at 2 kg/cm2 causes protein aggre gation, as shown by polyacrylamide gel electrophoresis. Sedimentation velocity experiments show that dry heating at 150-degrees-C and wet he ating at 2 kg/CM2 increase low molecular weight components (2S) while decreasing the percentage of high molecular weight proteins (11S). The gel filtration profiles of proteins from seeds treated at high temper atures (autoclaving at 2 kg/cm2 and dry roasting at 150-degrees-C) als o show an increase in the percentage of low molecular weight proteins. Heat-treated total proteins are less susceptible to proteolysis by tr ypsin and chymotrypsin.