The Preliminary Study On Functional Characters And Protein Structure During The Preparation Of Chicken Ham Sausage

In china, the total amount of meat had reached 68.657 million ton in 2007 while the products of meat had reached 2 million ton. The ham sausage is the most important products. In this paper, the formula optimization, functional characters and the structure of salt-soluble protein in chicken ham sausage are studied. The major results are as follows:1. Formula optimization of the chicken ham sausageThe influence of lipid, starch, sodium pyrophosphate and soybean protein isolate on hardness, springiness, cohesiveness and resilience in chicken ham sausage are studied by single factor experiments and orthogonal experiments in this article. Regression equation between the texture properties and the content of additions in the chicken ham sausage are established. The result shows when the formula includes 10% lipid, 4% starch, 0.4% sodium pyrophosphate, 1.5% soybean protein isolate, the chicken ham sausage has its optimum texture profile which the hardness, springiness, cohesiveness and resilience is respectively 1488g, 0.9, 0.73 and 0.28 through texture profile analysis and sensory evaluations. And lipid content has significant influence on hardness, cohesiveness and resilience while sodium pyrophosphate on springiness. What is more, we find that instrumental hardness can predict sensory general acceptability effectively.2. The changes of functional characters of chicken’s breast protein in ham sausage processingSolubility, water holding capacity, fat holding capacity and emulsifying capacity in chicken’s breast protein are studied during the course of ham sausage processing. The result shows that water holding capacity and fat holding capacity increase steadily to 82.92% and 1.2mL/g with NaCl from 0% to 2.88% in the course of salting. During the course of chopping, sodium pyrophosphate and soybean protein isolate is added to the chicken sausage. The former makes water holding capacity increased significantly while the latter increases fat holding capacity and emulsifying capacity. During the course of cooking, with the increasing temperature from 40℃to 90℃, solubility decreases significantly, and tends to 2.3mg/mL at last. And fat holding capacity also decreases significantly while water holding capacity increases. In the bath of 90℃, both fat holding capacity and emulsifying capacity decrease with prolonged heating time.3. The preliminary study on the structure of salt-soluble protein in chicken ham sausage processingWhen 2.16% NaCl is added to the chicken breast in the course of salting, the content of abstracted salt-soluble protein take 56.37% account of total protein. And there is no significant change in AA component of salt-soluble protein abstracted by different NaCl content. SDS-PAGE shows that 65.6KD protein is abstracted by 1.44% NaCl while more myosin is abstracted by 2.16% NaCl, and the content of 97KD, 56.5KD, 45KD, 39KDand 37KD proteins increase with NaCl content. Because of solvent effect and the change of protein conformation, the UV absorption peaks of salt-soluble protein violet shift totally with the increase of NaCl content. Contrast to water-soluble protein, the amide A and the amide B’s band intensities of salt-soluble proteins are both weaker in FT-IR spectra.During the course of heating, hydrophobic interaction and disulfide bond are the most important chemical forces which maintain protein gel net work. After cooking in 90℃water bath for 1h, hydrophobic interaction value reaches 0.55mg/mL, while the total sulfhydryl group reaches 5.99mol/10~5g and the active sulfhydryl group reaches 0.75mol/10~5g. With the increase of heating temperature and the prolonging of heating time, more and more salt-soluble proteins denature and precipitate. 210KD, 96.5KD, 43KD and some low MW proteins precipitate at 50℃while 56.5KD, 40KD and some other low MW proteins also precipitate at 60℃. 37KD protein is heat-resistant.4. The correlated analysis between the structure of salt-solubleproteins and functional characters in chicken’s breast proteinThought the correlated analysis between the structure of salt-soluble proteins and functional characters in chicken’s breast protein, we know that the peak gray of actin, whose MW is 45.8KD is extremely significantly correlated with water holding capacity and fat holding capacity while 39KD and 37KD proteins are significantly correlated with water holding capacity and fat holding capacity during the salting course.After heating in different temperature, the peaks gray of 96.5KD, 56.5KD proteins in salt-soluble protein precipitation are significantly negative correlated with the solubility and emulsifying capacity ,while significantly positive with water holding capacity. What is more, 56.5KD and 45.8KD proteins in salt-soluble protein precipitation are significantly negative correlated with fat holding capacity. After heating in different time, there is no correlations among the content of salt-soluble protein precipitation, solubility and water holding capacity, but the peaks gray of 56.5KD and 45KD proteins in salt-soluble protein precipitation are significantly negative corrected with fat holding capacity and emulsifying capacity. And the myosin whose MW is 210KD is significantly negative correlated with fat holding capacity.