The cow's diet affects the flavor of the resultant meat and milk. A 2003 Colorado State University study^[44] found that 80% of consumers in the Denver-Colorado area preferred the taste of United States corn-fed beef to Australian grass-fed beef, and negligible difference in taste preference compared to Canadian barley-fed beef.

Grass-fed beef is not standardized. Most is leaner than conventional feedlot beef, but some is equally marbled due to carefully managed grazing, excellent pastures, and improved genetics. Another technique for producing well-marbled grass-fed cattle is to keep the animals on pasture for two years or more. Most pasture-based ranchers dry-age the beef for 7–21 days, enhancing the flavor and tenderness of the meat