Study On The Effect Of Precooked Temperature On Processability Of Beef

Beef is favored by consumers because of its high protein,low fat and low cholesterol.With the rapid development of the economy and consumption,the demand for beef in our country is increasing rapidly.As the third largest consumer beef country in the world,there is a shortage of beef in China.In order to expand trade exchanges and cater to domestic demand,this project intends to introduce beef into prefabricated form to study the prefabricated degree of beef,and secondarily process prefabricated raw materials into traditional Chinese products to meet the needs of the domestic market and verify its application value.In this study,the effects of precooking temperature on the water retention of beef were studied by examining precooking loss,centrifugation loss,storage loss,and moisture content.Simultaneously,shear force,DSC(differential scanning calorimetry),and LF-NMR were measured.The changes in low-field NMR were further explored to explore the effect of precooking temperature on the quality of beef.The precooked raw materials were then processed into beef and dried beef products for reconstitution.The results were verified by testing the yield,tenderness,texture,and sensory scores of cured beef,and the yield,water activity,and LF-NMR of dried beef.The practicability of precooking raw materials for secondary retorting also provides a theoretical basis for product development of precooked beef.The main findings are as follows:(1)The effect of precooking internal temperature on beef processing performance: Precooking internal temperature had a significant effect on beef moisture content,precooking loss,centrifugal loss,and storage loss(p<0.05).The35-40℃ is the critical temperature control range for the change of its water retention performance.At the same time,the precooking temperature also had a significant effect on the shear force of beef(p<0.05),and 40℃ was its key temperature control point.The LF-NMR results showed that the peak area A21 of the less-flowing water significantly decreased,but the relaxation time T21 shifted to the left when it was greater than 45℃,that is to say,the degree of freedom decreased.DSC showed that the protein on the beef surface had been completely denatured under heating at 90℃,and the degree of protein denaturation increased as the internal temperature increased.(2)Effect of precooking heating temperature on beef processing performance:Precooked heating temperature had a significant effect on beef moisture content,precooking loss,centrifugal loss,and storage loss(p<0.05).Significant changes occurred at 90-100℃(p<0.05),and there was no significant difference between the two.Shear forces also undergo critical changes at 90-100℃.LF-NMR results showed that the peak area A21 of the non-flowable water at the heating temperature of 80℃ is closer to the raw meat.And as the heating temperature increases,the relaxation time T21 shifts to the right,the water degree of freedom increases.DSC showed that the beef surface was not fully denatured at 60℃ and 70℃,and the meat surface was completely denatured at a heating temperature of 80℃ or more.As the heating temperature increased,the degree of denaturalization of the meat increased.(3)The influence of different precooked raw materials on the quality of reprocessed beef marinated beef: Compared with the control group,the complete yield of precooked marinated beef did not show a significant difference(p>0.05),but semi-complete production is affected by the precooking temperature.The key changes occur at the internal temperature of 40℃ and the heating temperature of 90℃.Similarly,the precooking temperature had no significant effect on the sensory index of marinated beef(p>0.05),but its texture performance showed a significant difference(p<0.05).(4)The influence of different precooked raw materials on the quality of the second-processed dried beef: Compared with the control group,the complete production and semi-complete production of precooked dried beef showed significant differences(p<0.05),and at the internal temperature of 40 ℃ and the heating temperature of 90℃,there was a critical change in the yield.Precooking temperature had a significant effect on water activity and water distribution status of dried beef(p<0.05),and the results were better when the heating temperature was around 90℃and the center temperature was 40℃.Through precooking temperature research on beef processing performance and product quality after secondary processing,precooking processing technology suitable for secondary processing of ready-to-eat meat products was determined,which provided theoretical scientific basis for the development and processing of beef products.