Red and White Fiber Content and Associated Post‐Mortem Properties of Seven Porcine Muscles

SUMMARY The red fiber content of several porcine muscles was estimated by a histochemical method (affinity for Sudan Black B due to high intracellular lipid content) and a biochemical method (high succinic dehydrogenase activity). Even though the muscles varied widely in total lipid content, the histochemical method was comparable to the biochemical method in categorizing porcine muscles as red or white. Red muscles (> 40% red fibers) contained greater myoglobin concentrations and generally had longer post‐rigor sarcomeres than white (< 30% red fibers) muscles. Interrelationships of percent red fibers, succinic dehydrogenase activity, fat content, glycolytic rate, and post‐rigor contraction state were discussed.