Considering the large demand for marinated chicken breast meat, marinating is one of the most important processes in poultry industry. Moreover, tumbler machine plays an important role, in view of quality and economics, in marinating in industrial scale. In this study, 50 kg of chicken breast and 10 L of 3% marinating powder (meat base) were tumbled in a tumbler machine. Consequently, 9 runs of tumbling were performed at different values of vacuum percentage (70%, 80% & 90%) and rotation speed (14, 16 & 18 rpm), with the rest of parameters been fixed. Accordingly, the following properties were investigated: fat oxidation, pH, shear force value, expressible moisture value, surface color (= redness, =yellowness and = lightness) at two times (after marinating and after aging), and microbial characteristics at three times (after marinating, after aging and at the end of the storage). The results indicated maximum reduction in microbial count at the rotation speed and vacuum percentage of 18 rpm and 80%, respectively. Moreover, considering pH and fat oxidation,the rotation speed and vacuum percentage of 18 rpm and 90%, respectively, were recommended to achieve optimum outcome. This is while the rotation speed of 16 rpm and vacuum percentage of 90% showed the best results in terms of expressible moisture and color.