低钠复合盐体系中L-赖氨酸和L-精氨酸对肌原纤维蛋白结构及凝胶性能的影响OA

This study investigated the effects of a low-sodium salt mixture(0.4 mmol/L,concentration ratio of NaCl to KCl=2:1)added with L-lysine(L-Lys)or L-arginine(L-Arg)at concentrations of 1,3,and 5 mmol/L on the structure and gel properties of myofibrillar protein(MP)using the salt mixture added with 1 mmol/L pyrophosphate(PP)as the control.The results indicated that compared with conventional salt treatment(0.4 mol/L NaCl+1 mmol/L PP),the low-sodium salt+PP treatment slightly but not significantly improved the water-holding capacity,texture,and rheology of MP gels.Compared with its combination with PP,the low-sodium salt mixture combined with basic amino acids(L-Lys and L-Arg)promoted the transformation of α-helix into other secondary structures and induced alterations in the surface properties of MP.Furthermore,the addition of L-Arg significantly reduced the average particle size and increased the solubility of MP.The addition of 5 mmol/L L-Arg decreased the average particle size by 22.1％and elevated the solubility by 330.9％(P<0.05).The incorporation of basic amino acids enhanced the storage modulus(G'),reduced the cooking loss,and improved the water-holding capacity of MP gels.Low-field nuclear magnetic resonance(LF-NMR)analysis revealed that the addition of basic amino acids resulted in an overall shortening of the relaxation time of immobilized water in MP gels,which signifies a reduction in the mobility of water molecules within the gel matrix.Scanning electron microscopy(SEM)showed that the addition of basic amino acids promoted the formation of a more fine,uniform and compact microstructure during the heat-induced gelation of MP.In conclusion,basic amino acids(especially L-Arg)can significantly improve the solubility and gel properties of MP under the condition of"low sodium and no phosphorus",which provides a theoretical basis and reference for the development of healthy meat products.