For dry-aging, whole sides of beef or primal cuts are hung in open air at a temperature just above freezing and left to age for several weeks. Not only are the enzymes working on the muscle tissues during this time, but the meat is also slowly dehydrating. This concentrates the meat and changes the texture and flavor.
The benefit of this process is very tender meat with an intense flavor. The downside is that you lose quite a bit of the meat due to moisture loss, which decreases the yield and increases the cost per pound. Also, the surface of the meat usually needs to be trimmed away before the beef is portioned and sold, resulting in further loss of volume.
Wet-aging is a relatively recent technique that developed along with advances in plastics and refrigeration. In this process, cuts of beef are vacuum-sealed in plastic and shipped to the market. The aging takes place in the 4-10 days between slaughter and sale while the meat is in transit.
The enzymes still have time to tenderize the meat enough to make it acceptable, and the biggest plus is that there's no weight-loss in the meat due to dehydration. Wet-aging also costs less for the manufacturer since the meat doesn't need to be stored or monitored, ultimately resulting in a lower consumer cost.
Which is Better?
Honestly, it's a matter of preference. The biggest difference between the two kinds of meat is in the flavor. Dry-aged beef can be described as having a roasted, nutty flavor, while wet-aged beef can taste slightly metallic and lacks the same depth of flavor.
Unless the beef is specifically labeled as dry-aged, the meat you buy in the store has almost definitely been wet-aged. Most of us have come to associate the flavor of beef with wet-aged meat, to the point that dry-aged beef might not taste as palatable anymore.
You should definitely try some dry-aged beef if you have the opportunity. It costs a lot more and is harder to find, but it's worth knowing that there are other options out there.
What do you think?
Related: Good Beef: How to Find Local Meat