There's an old saying to the effect that your enjoyment of eating sausage is seldom enhanced by knowing how it is made. If this makes sense to you then move along, there's nothing for you here. . .

There's another old saying that the closer a cut of beef is to the horns or hooves the more tasty it is, but also tougher. There's a logic to this since the more exercised a muscle is the tougher it is. That's not the only consideration:

The toughness of a cut of beef depends upon the age of the animal. The older the animal, the tougher its flesh tends to be. But how does one determine the age of an animal when purchasing meat? One determines it by examining the color of the fat. The fat in the meat from an older animal tends to be yellow, compared to the meat from a younger animal, wherein the fat tends to be creamy white.

On the other hand, it’s important to note that an animal’s diet can also affect the color of the fat. For example, a free-roaming grass-fed animal’s fat tends to be more yellow in color than the fat in a factory-raised animal.

The outside layer of fat and the marbling between lean fiber muscles contribute to meat’s tenderness, and although fat meat is not popular, a cut with too little fat and marbling tends to be tough. This is why a roast with a thin outer layer of fat is tougher than one with a more generous layer.

The yellow color comes from beta-carotene. ß-carotene is a fat-soluble antioxidant that is healthful to consume. There is more of it in grass than there is in grain and other byproducts fed to confined animals. If health and flavor are your goals then you would seek out youngish grass finished animals with more yellow in their fat.

No matter the age or diet of beef the way in which it is cut and processed matters greatly, especially aging:

This process involves considerable expense as the beef must be stored at or near freezing temperatures. Also only the higher grades of meat can be dry aged, as the process requires meat with a large, evenly distributed fat content. For these reasons one seldom sees dry aged beef outside of steak restaurants and upscale butcher shops. The key effect of dry aging is the concentration of the flavor. The taste of dry-aged beef is almost incomparable[citation needed] to that of wet-aged with four weeks being a recommended minimum.

The process enhances beef by two means. First, moisture is evaporated from the muscle. This creates a greater concentration of beef flavor and taste. Second, the beef’s natural enzymes break down the connective tissue in the muscle, which leads to more tender beef.

Dry aging of beef is rare in the United States today is rare due to the significant loss of weight in the aging process.

This Wikipedia entry is a bit over the top (incomparable?), but it hits the main points. Aging improves flavor and tenderness while reducing moisture and it is rare except for foodie class meats . . . such as the grass finished beef that I produce. It does add cost since it takes time and space in a costly facility, the temperature and moisture controlled aging room of the processor, and it reduces the weight of the product. Beef is sold by weight so there is an apparent loss to the producer, though it was mostly water that was lost.

There is also wet aging in which the carcass is vacuum sealed into a bag and kept for 7-10 days at just above freezing. This is about the amount of time it takes to handle and ship it to a butcher for preparing retail cuts, so it has become the dominant practice. There is no water loss as with dry aging so the weight is constant, an important issue since beef is generally sold by the pound.

The very best way is to eat it super fresh, within hours of slaughter. After 12 hours rigor mortis has set in which makes it tough. Aging is about undoing rigor mortis as well as flavor intensification. It's similar to the rule for good sweet corn - get the fire started and the pot boiling and only then go pick the corn. Run.

We've always done dry aging, and since our animals are well finished they can be aged for longer periods. We currently dry age for 21 days. It's traditional. Since I'm a contrarian I want to try wet aging of our fancy grass finished beef and do a cook off with the crew. We'll do blind taste testing and evaluation. If nothing else it's a good excuse for a party.

Update:

BTW, we do have excellent Munich style brats made up with our grass beef. They're expensive due to the labor costs but I find them to be truly worth the price.