| Jinhua ham as a local traditional food, how to effectively control and evaluate its quality characteristics has always been the focus for relevant scientific, corporate and even local governments. The current identification methods for quality of ham generally concentrated on the exterior style, such as odor and flavor, while the high-quality ham quality evaluation still lacks standardized and effective methods. Protein is the main compotent for Jinhua ham, and its changes effect the quality of Jinhua ham, so it is meanful for studying protein of Jinhua ham. Two-dimensional gel electrophoresis technology is the core of proteomics, and they provide a new way for ham quality evaluation. With Two-dimensional gel electrophoresis technology, we will search the characteristics protein associated with the ham-quality, and it can offer the basis for further study of differences in the different ham quality.By optimizing the ham sample preparation methods, two-dimensional electrophoresis conditions and other related technical parameters, we established two-dimensional electrophoresis methods for Jinhua ham. Then we compared the maps of "Xuefangjiang," "Guanmei", "Zongze," and "Jinzi" ham. We chose "Xuefangjiang," "Guanmei" ham in different shelves, and studied the changes of their maps, and the main results are as follows:1, At the basic of the general two-dimensional electrophoresis parameters of pork, we found gel filtration desalting columns is the better method through comparing maps with different methods. This method can remove salt and improve the rate of protein extraction with high resolution and good reproducibility.2, By optimizing the pH, the sample volume, isoelectric focusing parameters and staining methods and so on, we established two-dimensional electrophoresis methods for Jinhua ham. The results show that the pH 5～8, the content of proteins 300ug, progressive boost mode can get better isoelectric focusing effects and reduce the horizontal stripes, and the improved silver staining method can detect more low abundance proteins, and it is suitable for gel analysis.3, Using the established 2-DE for ham muscle tissue, we analyzed four different brands of Jinhua ham. SDS-PAGE gel electrophoresis showed that differences in protein mainly distributed between 18.4KD and 66.2KD and between 45KD and 116KD. Separated by two-dimensional electrophoresis, the average protein spots of "Xuefangjiang", "guanmei", "Zongze" and "Jinzi" separately are 1238±7,1126±6,1067±9,1035±10. By software analysis we obtained significant different spots that between "Xuefangjiang" and "guanmei", between "Xuefangjiang" and "Zongze", between "Xuefangjiang" and "Jinzi", between "guanmei" and "Zongze", between "guanmei" and "Jinzi", between "Zongze" and "Jinzi" separately are 11,12,11,8,6,6.4, Using the established 2-DE for ham muscle tissue, we analyzed Jinhua ham with different shelf life. SDS-PAGE gel electrophoresis showed that differences in protein mainly distributed between 18.4KD and 66.2KD and between 45KD and 116KD. "Xuefangjiang" ham with different shelves were analyzed, the significant different protein points between adjacent two shellf time were separately 10,8,5,12,10. The "Guanmei" ham with different shelves were analyzed, the significant different protein points that between adjacent two shellf time were separately 11,8,7,8,4. During shelf time the different protein points can be divided into three categories:(1) The amount of the expressed proteins are almost the same during shelf life. The effect of this kind of proteins on the quality of ham is very small, almost negligible. (2) During shelf life some expressed proteins decreased or disappeared. Such proteins may be involved in degradation, and form smaller proteins or other small molecules. (3) During shelf life some expressed proteins increased. Such proteins may be come from the degradation of protein with large molecules, and this part of proteins increased with the add of original proteins and made this part of proteins increased.
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