Effect Of Tumbling On The Quality Of Beef And Its Mechanism

During the meat products processing,curing plays an important role to improve the texture attribute(tenderness,water holding capacity,flavor and color)of meat products and extend its shelf life significantly.However,the traditional method of curing are limited to be applied in industrialization because of time-consuming,serious waste of pickling solution and the evolution of unacceptable microbes.Tumbling assisted curing technology has been widely used in the meat processing and productions of China as a rising kind of meat processing technology,especially in the process of raw meat tenderizing,marinating and seasoning to improve quality.At present,the research objects on tumbling and curing are mainly concentrated in pork and poultry products.The research on beef is relatively small.The study has found that different Tumbling assisted curing techniques have different roles on different types of raw meat,and the research purpose mainly stays at the macro level such as the improvement of meat quality and the changes caused by it,but little on the changes of internal mechanismIn this study,without tumbling was used as the control group in comparison with three other commonly used curing methods in actual production: atmospheric tumbling,vacuum tumbling and pulsating vacuum tumbling-curing method.The measured changes of protein structure and functional properties based on the myofibrillar protein extracted from cured beef to explore the macroscopic quality of beef.Secondly,the change of texture attributes of myofibrillar protein formation during heat induced gel and the mechanism of beef quality change were analyzed for preliminary discussion.Finally,we employed different tumbling assisted curing technologies to produce the beef brained ham and thus to provide reference and theoretical guidance for the application of tumbling assisted curing technologies in processing used by enterprises.The result we achieved as follows:1.The changes of beef quality after tumbling-curing were as follows: we used the shear force,p H value,yield,microstructure of muscle fiber,water migration law and secondary structure of protein were used as indicators,while without tumbling as the control group.The results showed that using vacuum tumbling curing the minimum shear force of beef was 4.59,which was 58% lower than that of the control group.The p H value and yield of beef were significantly increased(P < 0.05).Free water were largely transformed in to the bound water that remains more stable.The content of ?-helix in the secondary structure of beef protein increased,and the protein system was more stable.Overall,tumbling assisted curing technology can improve the quality of beef,and the effect with vacuum tumbling is better than other groups.2.Compared with the control group,The results showed that the solubility of myofibrillar protein increased by 45%,and the turbidity and viscosity decreased significantly after vacuum tumbled-curing method(P < 0.05).The emulsifying activity and stability of protein solution were significantly improved after vacuum tumbled-curing method and pulsating vacuum tumbled-curing method(P < 0.05).At the same time,it was found that tumbled-curing could change the functional properties of beef myofibrillar protein?The total sulfhydryl content and active sulfhydryl content of vacuum tumbling-curing method and tumbling-curing with pulsating vacuum were higher than those of atmospheric tumbling(P < 0.05),the hydrophobicity of surface and the content of ditryl were significantly decreased(P < 0.05),and the content of ?-helix in protein secondary structure was significantly higher than that of control group(P < 0.05),showing a more stable tendency.However,there was no significant difference between the control group and without tumbleing-curing method(P > 0.05),which can not contribute to the protein structure and functional properties.3.The results of the study on the property of heat-induced gel of beef myofibril protein based on tumbled-curing method shows that the gel strength and gel whiteness of myofibril protein increased,which are better than those of the control group(P<0.05),the cooking loss rate decreased compared with the control group,the water holding capacity increased,and the overall water holding capacity of the gel significantly improved(P<0.05).Research on thermorheological properties found that tumbling-curing method can increase the elastic modulus of the protein and form a high-quality thermal gel.The water migration of protein based on the low field nuclear magnetic resonance(NMR)showed that tumbling-curing method could significantly increase the content of bound water while reduce the free water(P<0.05).After vacuum tumbling-curing and pulsating vacuum tumbled-curing,the relative content of the ?-helix of the protein gel increased gradually(P<0.05).The protein gel formed a uniform,dense and ordered microstructure.In conclusion,tumbling-curing method could effectively improve the properties of heat induced gel based on myofibrillar protein,and vacuum tumbling-curing had the best performance.4.The effect of tumbling-curing on the quality of beef brined ham showed that the yield rate based on vacuum tumbling-curing method reached 122.40%,an increase of 11.85% compared to the control group.The water holding capacity,texture and microstructure of vacuum tumbling-curing beef brined ham were improved,and the total score of sensory evaluation was the highest.The secondary structure of protein during vacuum tumbling-curing changed from disordered structure such as random curl to an ordered structure such as ?-helix,making its gel net structure more stable and its texture characteristics better.In summary,vacuum tumbling-curing method is particularly useful in the processing of beef brined ham,which can effectively improve the quality of products.