Experimental estimation of the viscous component of ultrasound attenuation in suspensions of bovine skeletal muscle myofibrils.
It has been suggested that viscous losses, caused by the motion of myofibrils relative to their environmental fluid, could be the major cause of ultrasound attenuation in muscle. This Paper presents theoretical and experimental estimates of the viscous component of attenuation in suspensions of myofibrils. Experimental estimates were made by monitoring the effects of varying the viscosity and density of the suspending fluid and ranged from 0.55 to 0.72 cm2 g-1 protein at 7 MHz, when expressed as mass attenuation coefficients. This represented 16-22% of the total attenuation measured in suspensions. Corresponding theoretical calculations were lower: 0.44 and 0.21 cm2 g-1 protein, respectively, for suspensions with the myofibrils aligned along and across the direction of sound propagation. It was concluded that most of the attenuation was caused by other absorption processes.
Shore
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AFRC Institute of Food Research, Bristol Laboratory, Langford, Avon, UK.
Miles
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CA
D000818:Animals; D002417:Cattle; D066298:In Vitro Techniques; D009210:Myofibrils; D014465:Ultrasonics; D014783:Viscosity