Does Grass-Fed Prime Rib Actually Taste Different Than Grain-Fed?

When you're selecting a prime rib for a special dinner, you're likely to be confronted with a number of choices. Of course, there are different grades of beef — prime (spendiest and best, with the fattest marbling), choice (more widely available and affordable, with good marbling), and select (least expensive of the acceptable options, with the least marbling), based on the USDA guidelines. But that's not your only decision to make, it's also common to find prime rib that's labeled as grass-fed. Understanding exactly what the term "grass-fed" means can help you pick the prime rib you'll be happiest with.

"Grass-fed" should be pretty straightforward, right? It would be, except for the fact that the North American Meat Institute says "All cattle are grass-fed" before continuing to explain that while all cattle do eat grass, not all of them eat grass exclusively. Some are fed grain, much of it corn, for a portion of their lives, usually right before they're slaughtered. Grain-fed cattle graze for most of their lives, spending the last four to six months in a feedlot, where their grain-based diet increases the fat content of the meat. Because grass-fed beef — which really means grass-finished, since all cows do eat grass at some point — is more expensive than grain-fed beef, the real question is whether there's a difference in flavor.

The short answer is yes, you will taste the difference between grass-fed prime rib and grain-fed. In addition to the fact that grass-fed beef tends to be leaner than grain-fed, it also has a different flavor. Serious Eats explains that grass-fed, grass-finished beef "tends to be a little more grassy and funky in its flavor than grass-fed, grain-finished beef, which tends to be richer." Lean and Tender Beef characterizes grass-fed beef as tasting "meatier and even more similar to game meat." Grain-fed beef, by comparison, according to Steak School, has "A more buttery flavor and brighter meat, along with whiter fat." 

America's Test Kitchen also said some people perceive grain-fed beef as more "mild" compared to grass-fed. There is, in fact, a difference in flavor between grain-fed and grass-fed beef, but that doesn't necessarily mean one is better than the other. When you're selecting your prime rib, you may factor in cost as well as flavor, knowing that paying more for grass-fed prime rib will, actually, make a perceptible difference in your finished product. Whether you prefer grass or grain is simply a matter of personal taste.