Brining serves the dual purpose of keeping meats moist and imparting deep flavors. Most beef cuts have sufficient fat to stay tender. Beef brisket is a leaner beef cut that does tend to dry out when smoked. Cold smoked brisket is often held in the bacterial danger zone below 140 degrees F for several hours. A curing agent in the brine can preserve the beef brisket and prevent dangerous bacterial growth during the smoking process.
Heat the water to a full boil in a large stockpot. Remove the stockpot from the heat. Stir in the kosher salt until it is all dissolved.
Add curing salts to the brine if the meat is slow smoking at cold temperatures. Smoking above 180 degrees F usually brings beef brisket to temperature fast enough to make the curing salts unnecessary. Curing salts add a flavor to the beef that many associate with cured ham.
Cover the stockpot with a lid and wait for the salty water to cool to room temperature. Add any seasonings you want to flavor the interior meat of the smoked brisket with to the cooled brine. Common choices for beef brines include juniper berries, cloves, peppercorns, coriander and garlic.
Lower the beef brisket into a large food-safe container. Pour cooled brine into the container until the beef is completely covered. Seal the container.
Place the sealed brine container in the refrigerator for seven days. Open the container and turn the beef brisket over in the brine with a clean fork. Reseal the container and allow the meat to soak for another three to 14 days, depending on the level of seasoning intensity you desire.