Analysis Of Differences Ofchinese Traditional Bacons And Pressure Varied Static Brining Technology

In this project, the comparative analysis of physicochemical properties, volatile flavor compounds and optimized parameters were carried out to research the influence of PVSB processing onsalting efficiency, meat quality, protein and microstructure of pork myolin. The results are as follows:(1) Sixty-seven samples from Hunan, Sichuan Guangdong, Jiangxi, and Yunnan Provinces in China were analyzed to understand their geographical properties. Classification was performed by determining their physicochemical properties through chemometric techniques, including variance analysis, principal component analysis(PCA), and discriminant analysis(DA). Results showed that certain differences existed in terms of nine physicochemical determinations in traditional Chinese pork bacon. PCA revealed the distinction among Hunan, Sichuan, and Guangdong style bacon. Meanwhile, seven key physicochemical determination criteria were identified in line with DA and could be reasonably applied to the classification of traditional Chinese pork bacon. Furthermore, the ratio of overall correct classification was 97.76% and that of cross-validation was 91.76%.(2) The discrepancies of volatile flavor compounds in Hunan style bacons, Sichuan style bacons and Cantonese style bacons using SPME-GC/MS and electronic nose were evaluated in this work. Principal compound analysis based on the data from electronic nose showed that the differences in aroma between Cantonese style bacons and others were observed, while Hunan style bacons were similar with Sichuan style bacons. 32, 38 and 42 volatile flavor compounds were identified from Hunan style bacons, Sichuan style bacons and Cantonese style bacons, respectively.(3) Atmospheric pressure brining, vacuum brining and pressure increasing brining were combined to Pressure varied static brining operation, the optimized method was identified based on the brining efficiency and sensory evaluation scores: varied pressure amplitude is-70 k Pa —Atmospheric pressure—160 k Pa—Atmospheric pressurein a circle, brine concentration is 15.87%, curing time is 5.22 h, pressure-transform alternation ratiois 6, pulsation ratio is 1.5.(4) Pressure varied static brining(PVSB-test group), atmospheric pressure brining(APB-control group 1), vacuum brining(VB-control group 2) and pressure increasing brining(PIB-control group 3), were employed to prepare cured meat. Subsequently, salting efficiency(salt content, marinade absorption) and various quality indexes including p H value, eating quality(water content, centrifugation loss, drop loss, color, shear force, TPA), salt-soluble protein content, microstructure of pork myolin and myofibrillar protein degradation were investigated. Test group for 4h resulted in higher salting efficiency than control groups(P<0.05). In comparison with control, the p H valueand eating quality increased. water content and water capacity of pork muscle treat with PVSB were increased significantly(P<0.05). The test group had lower shear force, hardness, springiness, chewiness and gumminess than control group(P<0.05). PVSB resulted in higher b* of the external than control groups(P<0.05), a*,b* of the internal and content of myoglobin had no significant differences among four treatment. The test group resulted in higher salt soluble protein in pork muscle and lower in marinade, respectively. The degree of myofibrillar protein degradation in test group and control groups was inconsistent. There was no apparent bands appeared or disappeared from 1.5 to 4.5h in test group, while it had 40 k D fragment appeared at 6h, but not apparent. All control groups had 40 k D fragment appeared. In was showed that test group resulted in lower protein degradation than control groups. During the curing, the muscle fiber bundles of the control groups were damaged seriously after curing.