Dry aging (hanging carcass beef in a cool, climate controlled environment) has a long history but the modern beef industry has abandoned it in favor of a poor substitute deemed “wet aging” where all the excess fluids associated with a beef primal cut are supposedly captured with it in vacuum sealed plastic.
Here is what Hugh Fearnley -Whittingstall, a British small holder , livestock raiser and food writer ( The River Cottage Meat Book) has to say: “What happens to the meat during hanging (dry aging)is that the natural enzymes begin to act on the fibers of the muscle meat, making them softer and more elastic so that the meat becomes more relaxed and tender.” “The meat will also begin to lose moisture as it hangs. Paradoxically this is a good thing when it comes to cooking. Wet, fresh, underhung meat carries too much water, which expands as the temperature rises during cooking, stretching the fibers of the meat and leaching out between them-especially when the meat contracts again after cooking and during carving. This means that wet meat actually ends up drier after cooking and vice versa.” “In general, another great but rarely discussed benefit of proper hanging… is that dry aged meat will emerge from the freezer with far greater credit than immature, wet meat. Again, moisture is a key issue. Water expands as it freezes so that ice crystals will tear and push apart the fibers of the meat.Not only will dry aged meat contain less of the damaging moisture but the more elastic fibers will cope better with the expanding ice crystals. So, as the meat defrosts , and again as it cooks , there will be less tendency for water to leach out.”
Remember that “dry meat” (dry aged) is “moister” than “wet meat” (fresh or wet aged) every time you discard the costly tray bib from a package of grocery store beef.