Cooking frozen Turkey: duration, yield and stuffing alterations with solid-state starting temperature

Abstract

Frozen pre-stuffed turkeys from 12 week females were conductively cooked at 163°C to an 85°C internal breast end-point. Bread cubes having 50% added water filled crop and body cavity to 20% of weight the turkeys were then frozen. Each of 4 treatments employed 7 carcasses: one was thawed to +5°C with repetitions at -5, -15, and -25°C enabling a regression analysis. Time to attain breast end-point was 44 min when the starting temperature was +5°C, which increased to 63 min at -5°C, and 69 min at -25°C (P < 0.001, Q: quadratic). Thigh temperatures averaged 77°C. Crop stuffing was 80°C when cooking was initiated at +5°C and increased to 84°C as the starting temperatures fell to -25°C (P < 0.01, Q). Body cavity stuffing reached 65°C when the carcass had been thawed prior to cooking, thereafter decreasing to 59 and 60°C when at -5 and -15°C, respectively, before returning to 65°C for the -25°C case (P < 0.01, C: cubic). Total carcass loss was 18.8% when cooking was initiated at +5°C. This increased to 22.6% at -25°C (P < 0.01, Q). Total drip after cooking averaged 23.7% however, the percentage of fat in the drip increased from 51.1% when using +5°C, to 57.2% with carcasses at -25°C (P < 0.05, Q). The stuffing gained in weight, which could be attributed to associated water when thawed, as opposed to frozen (147 vs. 102g, P < 0.05, Q). Stuffing moisture was less when the carcasses had been frozen than if cooked after thawing, particularly for crop (59.4% using +5°C vs. 55.8% frozen, P < 0.05, Q). Fat dominated the DM: increase, which was similar among treatments and both locations (22.6%). Stuffing CP: increased with +5°C carcasses on thawing compared to frozen carcasses, particularly for crop (15.1 vs. 13.2% DM, P < 0.05, Q from +5 to -5°C, respectively). Changes in part yield and meat composition were minor. Heat for ice to change to liquid was the primary basis for alterations when cooking from the frozen state, while cavity stuffing consistently failed to attain a safe temperature.