Tenderization of semitendinosus muscle using high intensity ultrasound

Semitendinosis muscle specimens, approximately 2.54-cm thick and weighing 200 g, were exposed to high-intensity ultrasound for periods of 0, 2, 4, 8, and 16 min. Four specimens were used at each period for a total of 20 specimens. A magnetorestrictive transducer produced CW ultrasound at a frequency of 25.9 kHz in a stainless steel tank filled with degassed saline. The semitendinosus meat specimens were cut either cross-sectionally or longitudinally to the muscle fibers. The cross-sectional cuts of the meat specimens were exposed to the ultrasound for periods of 2, 4 and 8 min while the longitudinal cuts were exposed for periods of 2, 4, 8 and 16 min. Tenderness was measured by Warner-Bratzler shear force by removing six 1.3-cm-diameter cores from each meat sample. For the samples exposed for 2 and 4 min, there was a statistically significant decrease in Warner-Bratzler shear force, which indicates an increase in tenderness for these specimens. These results suggest that high-intensity ultrasound is capable of tenderizing meat as assessed by an objective shear force measurement