Efficacy of tumbling in soy sauce marination of pork loins: effects of tumbling time and temperature

The objectives of this study were to determine the effects of tumbling time on the processing characteristics of soy sauce marinated pork loins, and to compare its efficacy at two different tumbling temperatures. In experiment I, pork loins (M. longissimus thoracis et lumborum) were pumped to 115% (w/w) of original sample weight with soy sauce solution (75%, w/w) and tumbled for 0, 1, 3, and 5 h. In experiment II, the soy sauce pumped pork loins were tumbled at two different temperatures (- 1 and 4 °C) for 4 h. The pH, color characteristics, water-holding capacity, protein solubility, and shear force of pork loins tumbled with soy sauce marinade were determined. An increase in tumbling time increased the cooked pH and yellowness of soy sauce marinated pork loins (p < 0.05). Protein solubility, particularly that of total and salt-soluble proteins, increased with increasing tumbling time (p < 0.05), and a tumbling time of at least 3 h may guarantee excellent water-holding capacity and shear force. In addition, low tumbling temperature of - 1 °C could positively contribute to the improvement of water-holding capacity and shear force of soy sauce marinated pork loins. In conclusion, this current study indicates that the efficacy of tumbling in soy sauce marination of pork loins is affected by tumbling time and temperature, moreover, tumbling at - 1 °C for at least 3 h could be an effective method in the experimental operating condition.