A novel EGCG-Histidine complex improves gelling and physicochemical properties of porcine myofibrillar proteins: Insight into underlying mechanisms

Herein, an EGCG-Histidine complex is prepared, characterized, and further used to improve gel properties of myofibrillar proteins (MP). Results of FTIR, XRD, UV–Vis spectroscopy showed that histidine is covalently bound to EGCG by Michael addition or Schiff base reaction to form EGCG-Histidine complex, and antioxidant activity of EGCG-Histidine complex is significantly increased compared to EGCG or histidine alone (P < 0.05). The addition of EGCG-Histidine complex results in cooking loss of gel decreasing from 66.7 ± 0.23 % to 40.3 ± 2.02 %, and improves rheological properties of MP, and enhances gel strength from 0.10 ± 0.01 N to 0.22 ± 0.03 N, indicating positive effect of EGCG-Histidine complex on MP gel formation, above results is supported by results of SEM, CD spectroscopy, SDS-PAGE, and tryptophan fluorescence. These results indicated that EGCG-Histidine complex can be used as a functional ingredient to improve gel quality of meat products.