Low-temperature enzymatic glycosylation minimizes AGEs in gelatin modification: Structure-function relationships.

This work aimed to investigate the effect of low temperature (-10 °C) enzymatic glycosylation with chitosan on the physicochemical properties of gelatin. Structural analysis showed that proper glycosylation changed the conformational structure of gelatin. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed the success of N-glycosylation between gelatin and chitosan using chymopapain as a catalyst in a water/ethanol system at -10 °C. Meanwhile, low temperature enzymatic glycosylation could alter the secondary structure of gelatin. Compared with other groups, the Ge-Ch-5:1 (gelatin/chitosan conjugate at a 5:1 mass ratio) showed reduction in syneresis (14.2 %) while water-holding capacity increased by 89.5 %, swelling power rose by 2197 %, and the clearance rates of ABTS+/DPPH radicals reached 93.8 % and 88.3 %, respectively. Additionally, the emulsion activity index improved to 0.99 and surface hydrophobicity increased to 33.45. Due to the side effects of chymopapain hydrolysis and the glycosylation reaction, Ge-Ch-5:1 exhibited lower melting temperature, gelling temperature, gelling strength, and storage modulus compared to gelatin and Ge + Ch.