What Is Beef Marbling?

Let’s talk about fat. There are two kinds of fat in cattle: intermuscular and intramuscular. The first one refers to those solid white chunks or strips of fat between the muscles. This is the fat you or your butcher trim off before cooking or eating because it doesn’t contribute to an elevated dining experience. If you’ve ever tried to eat cooked intermuscular fat, you understand why it’s the origin of the phrase “chew the fat.” It’s rubbery and, other than the charred exterior, can be unpleasant to eat.

Intramuscular fat, on the other hand, occurs inside the muscle tissue. It’s those flecks and streaks of white you see scattered among the red parts of the meat. When we say marbling, this is what we’re talking about. The name comes from its resemblance to swirled color patterns on marble and other kinds of stone. We’ll get to more on how it affects flavor in a moment.


The U.S. Department of Agriculture created grade standards for domestic beef to indicate uniform levels of safety and quality. They use a combination of subjective characteristics and electronic instrument data to place all U.S. beef into eight categories, although the top three grades are the ones most commonly available in stores and restaurants. The one you most often see at grocery stores is Select, which indicates lean but good-quality meat. Grades of Choice and Prime generally feature more steak marbling and a higher price tag, with Prime grade beef being sold almost exclusively to high-end restaurants.

The Japanese use an international grading system called BMS, or Beef Marbling Score. This system assigns a number between 1 and 12 to reflect a cut of meat’s overall marbling. USDA Prime grade maxes out at a BMS of 5, whereas luxurious Japanese Wagyu beef can score as high as 12.


When it comes to marbling in beef, fat equals flavor. Intramuscular fat liquifies when you cook meat, providing a kind of self-marinating effect. As the marbling melts, it infuses the meat with a savory richness and velvety texture. Each bite of a well-marbled steak delivers extraordinary juiciness and robust flavor beyond compare.


All Snake River Farms American Wagyu beef grades above USDA Prime. One of the marvelous qualities of Wagyu cattle is that they naturally produce more marbling than other breeds. Part of that marbling comes from the carefully controlled diet we feed our cattle, including local grass and other grains. But part of it is simply a genetic trait — which is why our founder gambled on importing Japanese Wagyu in the 1980s and crossbreeding them with domestic cattle.

Because our American Wagyu beef surpasses most other domestic beef in marbling, we developed four categories for our products by synthesizing the USDA and Japanese systems:

  • USDA Choice – BMS of 2 to 3, great flavor and tenderness, above average steaks
  • USDA Prime – BMS of 4 to 5, includes only about 5% of all domestic beef
  • SRF Black Grade – American Wagyu beef with a BMS of 6 to 8, superior to USDA Prime
  • SRF Gold Grade – American Wagyu beef with a BMS of 9+ that delivers a rich flavor and buttery texture