Thermophysical Properties of Beef Steaks of Varying Thicknesses Cooked With Low and High Grill Surface Temperatures

Abstract

The objective of this study was to determine the thermodynamic and physical properties of beef strip loin steaks of varying thicknesses and USDA quality grades cooked with high and low grill surface temperatures. Thermal characteristics described by changes in the denaturation temperature (between 55°C – 60°C) and enthalpies of protein denaturation (70°C – 75°C) both differed (P = 0.031 and P = 0.001, respectively) among thick steaks, with thick steaks cooked on a high grill surface temperature having a lower denaturation temperature and enthalpy compared with thick steaks cooked on a low grill surface temperature. No differences (P > 0.05) were observed among thin steaks for denaturation temperature or enthalpy. The elastic behaviors of the surface and center of the steaks were analyzed to determine how the microstructure of the beef responded to applied stress. The elastic behavior of steak centers was influenced in a three-way interaction (P = 0.029) between quality grade, steak thickness, and grill surface temperature. The elastic behavior of the surface of steaks was influenced by the interaction of quality grade and steak thickness (P = 0.031). These interactions, along with the differences in the thermal characteristic of proteins, suggest that the microstructure of steaks was affected by each cooking treatment group. Hardness, resilience, and chewiness were each influenced by a three-way interaction (P = 0.023; 0.014; and 0.030; respectively). Thin steaks possessed greater cohesiveness (P = 0.038) and shear force ( P = 0.007) values. Meanwhile, thin steaks exhibited lower springiness (P = 0.002). The measured alterations in thermal and physical proper- ties in the beef steaks suggest that the composition, thickness, and cooking regiments impact the microstructure of beef, and this was ultimately confirmed through textural measurements. The results of this research can be used in the design of cooking processes that match beef characteristics.