A total of 100 broiler breast meat was cooked at 176°C to internal temperatures of either 71, 73, 75, 77, or 79°C. Tenderness significantly decreased as internal temperatures increased. The decrease was most pronounced at 79°C with a 26.4% increase in Meullenet-Owens-Razor-Shear (MORS) energy compared to that at 71°C. The toughness-temperature coefficient (TTC, change in tenderness/1°C increase) was calculated to be 4.48% across the temperature ranges. Cooking loss increased constantly with the increase of internal temperatures and ranged from 15 to 27% across the range of endpoint temperatures. Poultry breast meat cooked to a higher internal temperature was in average less tender and also more variable in tenderness.