Effects Of High Pressure Processing And Calcium Chloride On The Gelling Properties Of Myosin-sodium Alginate Gel And Its Mechanism

Polysaccharides substitute for fat and non-sodium salt substitute for sodium, is an effective way to develop low-fat and low-salt meat products.As a new food processing technology,high pressure processing(HPP) is often combined with other means to improve the quality of meat products.The addition of polysaccharides and salts and applying HPP might be very beneficial to the development of low-salt and low-fat restructured meat products.Myosin,which is the most abundant and important protein of muscle, plays an important role on the gelling properties of meat and meat products. In this study,the effects of the concentration of CaO2 on the properties of chicken breast myosin gel containing 0.5%(w/w) sodium alginate(M-SA) and the HPP on the properties of myosin gel containing sodium alginate and calcium chloride (M-SA-CaCl2) were investigated.And the changes in gelling properties were explained with different methods, which in order to provide theoretical basis for the development of low-salt and low-fat meat products.The results indicated that:(1) The water-holding capacity (WHC) of M-SA gel was significantly (P<0.05) decreased with concentration of CaCl2,while the gel strength was increased.(2) The addition of CaCl2 could reduce the hydrophilic effect and solubility of M-SA; increase the relaxation-relaxation time(T22) of water proton,and weak the water mobility.High concentration of CaCl2 could change the viscoelastic character and enhance the thermal gelation abilities of M-SA.High concentration also could change the networked structure,enhancing the aggregation and reducing the holes.Those resulted in the increased gel strength and the decreased WHC of M-SA gel.(3) The water-holding capacity (WHC) of M-SA gel was significantly (P<0.05) increased with elevating pressure,while the gel strength was decreased.(4) HPP could significantly increase the turbidity of M-SA-CaCl2,accompanied by increasing the surface hydrphobicity and reactive sulfhydryl groups.HPP could damage the interaction with the polymer of SA-Ca2+, enhancing the mobility and solubility of M-SA-CaCl2;HPP also could reduce the binding force between SA and Ca2+ and increase the amount of hydrophilic group of the M-SA-CaCl2.These changes could result from the HPP-induced significant (P<0.05) increase of the surface hydrophobicity and reactive sulfhydryl contents, weakened thermal gelation ability of M-SA-CaCl2, and the reduced protein aggregation within mixed gel.HPP at 300-400MPa could weak thermal gelation ability of M-SA-CaCl2, and the reduced protein aggregation within mixed gel.Those resulted in the decreased gel strength and the increased WHC of M-SA-CaCl2gel.(5) It was interesting to find that combination of HPP、CaCl2 and SA level could bring about variation of properties of meat protein gels to meet defferent needs of customers.