Relationship between beef consumer tenderness perception and Warner-Bratzler shear force

The aim of this study was to determine consumer ability to discern different levels of beef tenderness established by Warner-Bratzler shear (WBs). A panel of 220 people evaluated 60 samples of longissimus thoracis using a 5-point intensity scale (1: very tough; 5: very tender). Samples differed for commercial category, breed of animals and ageing length of meat. Shear force was measured by Instron equipped with a Warner-Bratzler device on 1.27cm diameter cores. Correlation coefficient of WBs measurements with tenderness sensory ratings was -0.72. WBs value corresponding to class 3 of the sensory tenderness was 47.77N. From this value, the range of WBs (22.96-72.59N) was split into five categories to which connect the five classes of sensory tenderness. The results suggest consumers' difficulty in discriminating category 1 (WBs>62.59N) from category 2 (WBs: 52.78-62.59N) and a greater inclination to distinguish category 5 (WBs<32.96N). As WBs category boundaries were probably too restrictive for the panel's selective ability, WBs scale was reduced to 3 categories by joining the two extreme categories (i.e. category 2 with 1 and category 4 with 5). In this case, 55.6% of consumers significantly discriminated tough from intermediate and tender meat and 62.3% distinguished tender from intermediate and tough meat (P<0.01). Hence, WBs values >52.68N and <42.87N allow classification of tough and tender beef in a sufficiently reliable way.