Tenderness and collagen composition of beef semitendinosus roasts cooked by conventional convective cooking and modeled, multi-stage, convective cooking

Beef semitendinosus roasts were cooked in a forced-air convection oven usin g conventional or modeled, multi-stage cooking. Conventional cooking was de fined as cooking at 163 degrees C to a core endpoint of 65 degrees C. The m odel method was developed using a finite difference heat and mass transfer model optimized for a three-stage cooking process that included preheating, holding, and finishing. Model cooking resulted in lower (P < 0.05) Warner- Bratlzer peak shear force values than conventional cooking (3.3 vs 4.7 kg). Collagen total unaltered fraction was lower (44 vs 55%, P = 0.05) and enzy me labile fraction was higher (56 vs 45%, P < 0.05) in the model-cooked sam ples than in conventionally cooked samples. The three-stage cooking process results in a more tender product without adversely affecting product yield . (C) 2000 Elsevier Science Ltd. All rights reserved.