Study On Microscopic Quality And Molecular Regulation Mechanism Of Low Sodium Salted Meat Products Based On Polyhydroxy Alcohol-mediated Curing

Sodium chloride,as a common salty flavoring agent,is widely used as a curing agent in salted meat products.However,most salted meat products contain high levels of sodium chloride,which poses a risk of cardiovascular diseases.Salt reduction has become a hot topic in the field of food science.Nevertheless,traditional salt reduction curing techniques have certain limitations,lacking the research on exogenous substances within the curing system that can remove meat matrix and traditional curing agents,while also influencing the curing process.Therefore,this study proposes a"mediated curing"strategy based on exogenous media other than table salt,aiming to achieve low-sodium curing of meat products by using exogenous food additives as media to affect salt permeation and diffusion pathways and moisture migration in the meat matrix.The focus of this study is on the excellent food permeation enhancer,polyhydroxy alcohols.Firstly,we investigate the effects of polyhydroxy alcohol-mediated curing using different polyhydroxy alcohols on the quality and microscopic structure of minced pork loin.Subsequently,we explore the impact of polyhydroxy alcohol-mediated curing with different polyhydroxy alcohols on the structure and functionality of myofibrillar protein(MP)in minced pork loin.Finally,we employ molecular docking and molecular dynamics simulations to reveal the theoretical mechanisms of polyhydroxy alcohol-mediated curing,providing a theoretical basis for the future application of polyhydroxy alcohol-mediated curing in meat products.The main conclusions are as follows:(1)Firstly,the effects of different polyhydroxy alcohol-mediated curing on the quality and microstructure of pork tenderloin mince were investigated.The tissue structure and moisture status of the minced meat were evaluated using low-field nuclear magnetic resonance(LF-NMR)and scanning electron microscopy(SEM).The use of polyhydroxy alcohol-mediated curing significantly reduced the salt content and A_w(p<0.01)and improved the water holding capacity and texture of ground pork tenderloin.LF-NMR and SEM analyses revealed that curing with 1%glycerol,1%xylitol,1%sorbitol,and 10%glycerol led to reduced water migration,enhanced water holding capacity,and the development of more uniform and compact microstructures.(2)The effects of different polyhydroxy alcohol-mediated curing on the structure and function of minced pork tenderloin MP were investigated.Results obtained from total sulfhydryl groups,surface hydrophobicity,fluorescence and Raman spectroscopy,and solubility showed that polyhydroxy alcohols(especially xylitol)significantly improved the MP tertiary structure,making the structure more hydrophobic and compact.However,no significant differences were detected in the secondary structure.Furthermore,the thermodynamic analysis showed that polyhydroxy alcohols could develop an amphiphilic interfacial layer on the MP surface,significantly increasing the denaturation temperature and denaturation heat thermal energy(p<0.05).(3)Polyhydroxy alcohol-mediated curing is an effective approach to reducing the salt content in cured meat products.To investigate the underlying mechanisms,molecular docking and molecular dynamics simulations were performed to reveal how different polyhydroxy alcohols mediate curing.The simulations showed that polyhydroxy alcohols interact with actin through hydrogen bonding and van der Waals force,leading to a more compact actin structure.This reduces the impact of high levels of salt ions on MP denaturation and improves the quality of cured meat.These findings provide a theoretical basis for the application of polyhydroxy alcohol-mediated curing in the cured meat industry.