A mapping method for the description of Warner-Bratzler shear force gradients in beef Longissimus thoracis et lumborum and Semitendinosus.

A novel approach to mapping Warner-Bratzler shear of whole muscles was explored. The procedure was used on the Longissimus thoracis et lumborum (LTL) and Semitendinosus (ST) from six beef cattle by first marking skeletally defined anatomical landmarks on the muscle in situ. After removal from the carcass, further divisions were made while preserving sample orientation during cooking and preparation for shearing. Shear gradients were observed in all planes of the LTL, particularly the medial-lateral. The mid-section of the ST had the lowest shears while superficial locations of the cross-section had greater values. Muscle comparison indicated the ST was more uniform than the LTL. The mapping technique was subsequently used to identify localized effects of altered carcass suspension on shear values and sarcomere length in the lumbar Longissimus from four beef cattle. This mapping method will provide guidance for further intensive investigation across the carcass musculature and under varying carcass conditions.