Improvement of meat tenderness by simultaneous application of high-intensity ultrasonic radiation and papain treatment

The present study aims to develop a novel process for improving meat tenderness. Three muscles were selected among five young Holstein bulls Longissimus lumborum muscles and were cut into 3 × 3 × 3 cm pieces. Samples were sonicated by ultrasonic probe (20 kHz) at power of 100 and 300 W for 10, 20, and 30 min both in the presence and absence of 0.1% papain enzyme solution. The effects of treatments were investigated on proteolytic activity, filtering residues, Warner-Bratzler shear force (WBSF), meat textural profile (TPA), and muscle microstructure. Application of enzyme, either singly or coupled with ultrasound significantly (P < 0.05) decreased the filtering residue, WBSF and textural parameters. The most proteolytic activity and the highest tenderness were obtained when the combined treatment was applied at ultrasonic power of 100 W for 20 min. Finally, the results showed that, combined treatment can be employed as a useful tool for the meat tenderization.