Lettuce should be part of any healthy diet; most varieties are highly nutritious, packed with antioxidants and are a good source of roughage. The darker your lettuce is, the more nutritious it is. Keeping a lettuce whole while storing it in the refrigerator is the best way to keep it from turning brown. If you need to cut your lettuce before storing it, a few simple steps will help you prolong its fresh taste and green leaves. A cut lettuce can be kept for up to 1 week using this method.
Rinse your lettuce. Cut the bottom off with a plastic knife. A metal knife may cause your lettuce to turn brown.
Cut your lettuce into small pieces with your plastic knife, or use your hands to tear it apart.
Place paper towels in the bottom of a sealable plastic container. Place the lettuce pieces on top of the paper towels, which will absorb any moisture. Cover the lettuce with another layer of paper towels.
Seal your container and place it in the crisper section of your refrigerator at a temperature of 00 degrees Celsius. Keep quick-ripening fruits, such as apples, apricots and melons, in another part of the refrigerator, as they emit ethylene gas when the ripen. The gas will make your lettuce turn brown quicker.
Check the paper towels every couple of days; if they are wet replace them with dry paper towels. The key to keep lettuce fresh for as long as possible, and to stop it from wilting and turning brown, is to reduce moisture. Paper towels will absorb the moisture and keep it away from your lettuce.