The Effect Of Ultrasound Combined With Calcium Chloride On The Ultrastructure And Tenderness Of Beef

In this experiment,the effects of different treatments on beef quality were determined by measuring the microstructure and mechanical indexes of different tender treatments for beef.Connective tissue was treated by acetic acid,ultrasound and heating,and the ultrastructural changes of collagen fibers were measured to analyze the structural stability of connective tissue under different treatment methods.The effects and mechanism of ultrasonic and CaCl₂ separate treatment on beef tenderness and other indicators were determined.On this basis,the appropriate range of ultrasonic intensity and concentration of CaCl₂ used for combined cross processing,and the optimal treatment method was determined through the changes of sarcomere length,shear force,water retention,color and internal enzymes,so as to obtain the mechanism of the effect of ultrasound and CaCl₂ on the internal structure of beef.The changes of meat quality under different processing methods were measured in order to provide theoretical basis for meat processing.?1?The effects of acetic acid,ultrasound and heating on collagen fibers were studied by measuring the D-spacing of collagen fibers,the height difference between gap and overlap,and the height of collagen fibers.The results showed that low concentration of acetic acid could maintain the intact structure of collagen fibers.However,after the superposition of ultrasonic and heating treatment results on acetic acid and the comparison with ultrasonic and heating results in the homogenated group,it was found that although acetic acid could maintain its complete structure,it had destroyed the internal cross-linking of collagen fibers.Therefore,when ultrasonic and heating treatment were added,the structural damage was more serious than that in the homogenated group.?2?The effect of ultrasonic and CaCl₂ treatment on beef quality was studied through the measurement of sarcomere length,shear force,water holding capacity,colors,calpains,desmin and troponin-T.The results showed that ultrasound treatment had a certain effect on the length of the sarcomere length,but could not improve meat tenderness,significantly change the water holding capacity and colors of the meat,or activate the calpains to activate its subunit to degrade the skeletal protein.CaCl₂ treatment can increase the length of the sarcomere length and improve its tenderness value,but it also has no significant influence on such indicators as water retention and colors.However,it can activate the calpains in the muscle fiber to degrade its subunit and exert its degradation effect on the skeletal protein of the muscle fiber.?3?According to the results of the second part,the ultrasonic intensity and CaCl₂concentration of the combined treatment were determined.Sarcomere length,shear force,water holding capacity,colors,calpains,desmin and troponin-T were measured after combined treatment.The results showed that the combined treatment could promote the Ca²⁺movement by ultrasound,activate the calpains subunit,and play a role in the degradation of fiber skeletal protein,thus improving the length of sarcomere and significantly improving the tenderness of meat.At the same time,the combined processing improved the water holding capacity of the meat samples by reducing the cooking loss.It could not significantly affect the colors,but kept the bright red color of the meat samples preferred by consumers.And through the comparison of the combined treatment results of each group,it shows that the tendering effect is the best under the treatment of 900 W/m² ultrasonic intensity and 0.3mol/L CaCl₂ concentration.