Ken Prusa, a professor of food science and human nutrition at Iowa State University, said that's because a deeper, richer red pork can indicate a higher pH than lighter pork. That means the darker the pork, the less acid it contains that damages muscle proteins and causes meat to be pale, watery and more sour.

Prusa, who has been researching ways to improve pork quality since he joined the Iowa State faculty in the mid–1980s, described the flavor of the darker meat as sweeter and nuttier.

"Higher pH products are more tender, juicy and flavorful," he said.

In the 1980s, Prusa said the pork industry was pushing for a leaner pork and launched "The Other White Meat" marketing campaign meant to highlight pork as a healthy alternative to poultry.

Source: The Hawk Eye