Tenderness is one of the most important traits in beef quality, and Wagyu is famous for its high-quality tenderness. Figure 5 shows the relationship between fat level and tenderness expressed as a Warner–Bratzlar shear-force value (SFV). SFV ranged from 2.08 to 4.56 kg/cm2 and a significant negative correlation was observed between the SFV and fat level, which ranged from 4.8 to 39.0% (r2 = 0.62, P < 0.05).