Things You'll Need
Rectangular pan that is only two inches or so deep
Several large immaculate white cotton dish towels
There are two kinds of aging when it comes to beef: wet aging and dry aging. Wet aging is when the beef is put into a vacuum sealed plastic bag and allowed to age in its own juices. Wet aging takes less time than dry aging, generally around seven days. Wet aging is the type of aging that most butchers do now. Dry aging is different though, and is actually when you want the beef to dry out. It takes anywhere from seven to twenty-one days to dry age beef. The reason people like dry aged beef is that the process allows the moisture in the muscle to evaporate, and this gives the meat a beefier flavor. Also, the beef is naturally tenderized because of the fact that the enzymes in the beef are breaking down. One thing to keep in mind is that you cannot dry age single steaks because they are too thin. For the purposes of this article you will need a piece of beef such as a whole ribeye or a whole loin strip.
Rinse your piece of beef with cold water.
Dry the beef well with one or two large white dish towels. Set it aside for a minute and allow it to drain.
Put your pan and wire rack on the bottom shelf of your refrigerator (because this is where it is coldest).
Wrap your beef in another of your large white dish towels and put it on the rack. Using your thermometer measure the temperature, you don't want a temperature any warmer than 36 degrees F.
Change the towel(s) wrapping your beef daily. Empty and rinse the pan daily as well. This is to ensure that your beef stays as dry as possible and that hopefully no mold or any other kind of bacteria has a chance to start growing.
Age your beef for ten days to two weeks. Cut off anything on the outer layer that is dry, crusty, or that seems like it could be bad for you to eat such as if you notice some green mold growing for example.
Store dry aged beef in your refrigerator for up to twenty-one days. If you haven't eaten all the beef in twenty-one days, cut the rest of it into steaks. Put it in freezer-proof, heavy duty plastic wrap, or plastic bags and put it in your freezer.
To get your white dish towels clean soak them in cold water overnight. Then soak them in cold salted water for 2 to 3 hours. This will get out any blood stains. Then just wash them like you normally would. Check your thermometer daily to make sure the temperature isn't above 36 degrees F. If it is any warmer it could cause the meat to spoil. Use only USDA Prime or USDA Choice that is yield grade 1 or 2 only cuts of meat when dry aging beef. The reason for this is that these have a thick layer of fat that will prevent your beef from spoiling while you dry age it.
If you see anything on your beef that looks like it could harm you if you ate it at any time, be sure and cut it off right away, so there is little to any chance that you accidentally give yourself food poisoning. One thing to bear in mind before you decide to dry age beef at home is that The National Cattleman's Beef Association does not endorse dry aging beef at home because of concerns about beef spoiling and people getting food poisoning. Only get into your refrigerator when you really need to. Don't be constantly opening it to check on your beef as this could disrupt the even temperature necessary to dry age your beef, and could make the beef spoil before the process is complete.