Hydrolysates\nfrom Sorghum Crude Kafirin Extract Exhibit\nIce Recrystallization Inhibition Activity

Ice recrystallization can damage\nthe microstructure of\nfood products,\nand one potential solution is the use of molecules with demonstrated\nice recrystallization inhibition (IRI) activity. The objective was\nto determine the IRI activity of sorghum kafirin hydrolysates as affected\nby succinylation and the dispersing medium. The IRI activity of the\nsorghum kafirin hydrolysates was analyzed by the splat assay in phosphate-buffered\nsaline (PBS) and 10 mM NaCl. At 2% concentration, sorghum kafirin\nhydrolyzed by bromelain for 1 h resulted in 55% reduction in ice crystal\nsize in 10 mM NaCl, while this was not observed when the dispersing\nmedium is PBS. Succinylation at 0.25:1 molar ratio (succinic anhydride:\namine group of the peptides) yielded modified hydrolysates that were\nslightly more IRI active in PBS, but the difference was not significant.\nThe data showed the potential application of sorghum kafirin hydrolysates\nto act as antifreeze molecules to preserve the quality of frozen materials.