Phosphate marination of pork loins at high and low injection pressures

Whole, boneless pork loins, divided into anterior and posterior sections, were injected with deionized water or sodium tripolyphosphate/NaCl solution at an injection pressure of 200 or 345 kPa with a constant injection level of 13%. A vacuum tumbling process subsequent to injection at 345 kPa was also evaluated. Increasing injection pressure of STPP/NaCl marinades improved cook loss, overall yield, but increased Warner-Bratzler shear values of water-only injected loins. Overall yield ranged between 84.6-98.1% for phosphate treated loins compared with yields of that ranged between 61.0-67.7% for no treatment and water injected controls. Posterior loin sections exhibited greater weight loss after 4 days storage than anterior sections. A significant marinade/position interaction was observed for total moisture. Tumbling of pork loins after needle injection increased overall yield.