Effect Of Pulsating Positive And Negative Pressure On Pickling Of Duck

Brining is the key step in meat processing,which contributes a typical salty taste and influences the development of a proteolysis phenomena affecting texture and flavour. However, curing is a very time consuming process.The length of the curing time directly affects the production efficiency and economic benefit of the production enterprises.The salt content of traditional dry-salting products may be high and of low homogeneity, which consequently causes the poor sensory quality and great quality fluctuation of salted meat products. So exploring new curing process caused widely attention of scholars.A series of experiments from choosing the cured method, optimization parameters and the impact on meat quality. A total of three sections are included in this study, the contents and results are as follows:1. Effect of different curing strategies on curing rate andquality index of duck meatTo investigate the effect of vacuum and pressure on curing rate and duck meat quality, this study evaluated the pulsed vacuum brining (PVB), pulsed pressure brining (PPB), vacuum and pressure combined brining (VPB) on the curing rate and the quality indexes of duck meat samples including pH, cooking loss, protein content and shear force, with atmospheric pressure brining (APB) as the control. Results showed that the salt content of the muscles after APB, PVB, PPB, and VPB treatment was 2.61%,3.01%,2.91%,3.21% respectively. The pH-value showed a declining trend without significant difference between the four treatments (p>0.05). Compared with that of APB, PVB and VPB could reduce the cooking loss, while PPB increased the cooking loss. After curing for 4h, the shear force of the muscles treated by APB, PVB, PPB, and VPB was 1076g,938g,1093g,908g respectively, and the shear force PVB and VPB treated muscles were significantly different from that of APB, (p<0.05), whereas there was no significant difference between PPB and APB brined muscles (p>0.05). Protein content of PVB, PPB and VPB treated muscles all greatly increased compared with that of APB (p<0.05). On the whole, with regard to the curing rate and duck meat quality, the VPB treatment had more advantages than PVB and PPB.2. Optimization of the technical parameters for pulsed vacuum and pressure combined brining of duck muscleThe effect of pressure, vacuum and vacuum holding time/pressure holding time on the saltcontents of duck breast meat were studied by single factor design. Based on the single factor experiments, the pulsed vacuum and pressure combined brining were optimized by response surface methodology according to the Box-Behnken central composite designs experiment. Results showed that the optimum parameters for pulsed vacuum and pressure combined brining were at the pressure of 0.12MPa, vacuum of 0.084MPa, and the vacuum holding time/pressure holding time of 1.56. Under these conditions, the predicted salt content and the actual salt content were 3.71% and 3.65% respectively, the deviation was 1.64%. The optimized of the pulsed vacuum and pressure combined brining parameters of salted duck by response surface analysis methods was accurate and reliable, which gaved a technical reference for the fast salting of duck muscle.3 Effect of pulsed vacuum and pressure combined brining on quality changes of duck muscleTo investigate the effect of optimal conditions of pulsed vacuum and pressure combined brining, The moisture content, meat color, TVB-N, TBA, free amino acid, fatty acid profiles and microstructure were measured in comparison with that cured at atmospheric pressure. The results showed that pulsed vacuum and pressure combined brining accelerated moisture content, free amino acid content, saturated fatty acids, and polyunsaturated fatty acids, while it lowered a*, TVB-N, and TBA as compared to the control. Pulsed vacuum and pressure combined brining had no significant effect on L*, b*. The sarcomere length became remarkably longer, and the gaps between muscle fibers became larger after pulsed vacuum and pressure combined brining compared with muscles salted with atmospheric pressure brining.