Ice Structuring Peptides from Alcalase-hydrolyzed Fish Gelatin: Process Optimization, Peptide Isolation and Characterization

摘要

Ice structuring peptides from alcalase-hydrolyzed fish gelatin was first reported in this study. The inhibition of ice recrystallization in an ice cream mix matrix and in sucrose solution by collagen peptides derived from Alcalase hydrolysis of fish gelatin was investigated. Optimum conditions for producing ice structuring peptides from gelatin was determined as pH 9.0 at 45 C for 25 min and an Alcalase-to-gelatin ratio 0.176 units per gram gelatin. The collagen peptides were fractionated on size exclusion（Sephadex G-50）ion exchange（sulfopropyl-Sephadex C-25）columns, and the molecular mass distribution of the ice structuring peptide fractions was determined by matrix-assisted laser desorption ionization 儃 time of flight（MALDI-TOF）mass spectrometry. The gelatin hydrolysate fraction containing peptides in the molecular mass range of 800儃3300 Da inhibited ice recrystallization in a super-cooled ice cream mix and in concentrated sucrose solutions. The more cationic collagen peptides with molecular weight in the range of 1100-2000 Da were more effective in inhibiting ice crystal growth.