The effects of different cooking regimes on the cook yield and tenderness of non-injected and injection enhanced forequarter beef muscles.

The aim was to investigate the effect of different cooking regimes on the cook yield and tenderness of non-injected and brine injected (0.5% residual NaCl) bovine M. triceps brachii caput longum (TB), M. supraspinatus (SP) and M. pectoralis profundus (PP). Injected and non-injected TB, SP and PP muscle sections (400 g) were (a) conventionally oven cooked to 72 degrees C or cooked slowly (using a Delta10 programme) to 72 degrees C or (b) cooked in a water bath to 72 degrees C or cooked in a water bath to 55 degrees C and held at this temperature for 2 h before heating to 72 degrees C. In addition, injected PP muscle sections were oven cooked to 69 degrees C and held at this temperature for up to 12 h. Slow cooking using a Delta10 programme had no significant (P<0.05) effect on WBSF values of injected or non-injected SP and TB muscles but significantly (P<0.05) decreased the WBSF values of injected and non-injected PP muscles when compared to conventional cooking. Slow cooking significantly (P<0.05) increased % cook yield of injected PP, SP and TB muscles. Staged cooking significantly (P<0.05) decreased the WBSF values and had no significant effect on sensory tenderness ratings of non-injected TB, SP and PP muscles and injected PP muscles. Staged cooked injected or non-injected PP, SP and TB muscles had lower % cook yield values than those cooked straight to 72 degrees C. Increasing the cooking time of injected PP muscles at 69 degrees C to 8 and 12 h decreased % cook yield, decreased WBSF values and increased sensory tenderness ratings. It also alleviated the problem of residual chewiness which was evident in PP muscles cooked using the other regimes.