The impact of ultrasound and vacuum pack on quality properties of beef after modified atmosphere on display

Beef steaks (L. lumborum and Semitendinosus) were randomly assigned to one of three treatments: 1) No-ultrasonicated; 2) 16 W/cm(2) or 3) 28 W/cm(2) ultrasonicated in vacuum bags (VAC). Later, steaks were also randomly packed in either VAC or modified atmosphere (MAP, 25-75%, CO2-O-2). After simulated retail display (SRD, 3 degrees C, 12 h light) for 6 d, High-intensity Ultrasound (HIU) increased redness and saturation on VAC meat (p < 0.05) and produced an increase on L. lumborum (p < 0.05) but not on Semitendinosus (p > 0.05) shear force. High concentrations of O-2 in MAP increased loss of redness (2.83 vs. 2.13 MAP vs. VAC, respectively) and saturation (2.64 vs. 1.99, respectively) during SRD. MAP also increased L. lumborum shear force (4.4 vs. 3.2 kgf, respectively p < 0.001) and lipid oxidation (p < 0.001). HIU may be consider as a strategy to improve beef color on VAC. Moreover, high O-2 concentrations on MAP should be used with caution for beef, because of a possible negative impact on oxidative stability and tenderness.