Macroscopic wrinkling of muscle fibres, a source of error in objective assessment of meat toughness.

Post-rigor shortening of muscle resulting in macroscopic fibre wrinkling was studied in muscle samples which entered rigor restrained in a stretched condition and were subsequently freed. The amount of wrinkling varied with the initial degree of stretch pre rigor and with the muscle treatment post rigor, depending on such variables as (1) whether or not the muscle was heated and (2) if heated, at what stage the restraint was removed. The consequences of fibre wrinkling relative to the objective testing of meat toughness are discussed.