The conversion of muscle to meat

Postmortem changes that occur during the process of converting muscle to meat play a critical role in the development of quality traits and the overall acceptance of the fresh product. After an animal is harvested, muscle glycogen along with high-energy phosphate compounds is anaerobically metabolized in an effort to maintain adenosine triphosphate (ATP) homeostasis. As a consequence of postmortem glycolysis, lactate and hydrogen ions accumulate in the muscle and cause a drop in pH. Ultimately, postmortem metabolism is arrested due to substrate depletion or the inactivation of the glycolytic enzyme phosphofructokinase-1, resulting in ATP depletion and the development of rigor mortis. The muscle subsequently undergoes proteolytic disruption of myofibrillar proteins, thereby improving meat tenderness and flavor. Factors such as genetics, nutrition, environmental conditions, and pre- and postmortem handling can drastically influence the conversion of muscle to meat and ultimately end-product quality.