Lettuce is one of the world’s most popular edible plants, serving as the basis for most salads, and adding texture and color to sandwiches. Quite possibly, lettuce is eaten more often than any other vegetable. Depending on the variety, the texture of lettuce ranges from crisp to velvety, and its flavor from mild to assertive and peppery. Lettuce is in the daisy family (Asteraceae).
The ancient Egyptians grew lettuce some 4,500 years ago in the Nile Valley, and lettuce plants appear in hieroglyphics. It was the Egyptians who transformed the wild lettuce plant (whose seeds were harvested for their oil) into a vegetable plant. The Romans—for whom romaine lettuce is named—grew many varieties, and ultimately bequeathed us the word “lettuce” itself, derived from Latin lactuca. Christopher Columbus introduced lettuce to the New World on his second voyage. By the mid-1800s, lettuce was regularly eaten throughout Europe and North America, and by the late 1900s its popularity had spread worldwide.
Most lettuce supplies a small amount of vitamin C, and modest amounts of beta carotene, the carotenoids lutein and zeaxanthin, vitamin K, the B vitamin folate, and the mineral iron. Still, compared with many other leafy green vegetables, lettuce offers low amounts of essential nutrients, with iceberg lettuce at the bottom of the list. A good rule of thumb is the color of the lettuce: the darker and more colorful the leaves the greater the nutrient content. Whatever its intrinsic nutritional value, lettuce does serve as a perfect salad backdrop for more nutrient-dense vegetables such as tomatoes, bell peppers, corn, avocado, broccoli, beets, and carrots.
How to store lettuce at home
If you don’t plan on using the lettuce right away, store unwashed greens in perforated plastic bags. If you’ve bought the lettuce in plastic bags, poke a few holes in the bag to allow air to circulate, and leave the bag open. Soft-leaved lettuces do not keep as well as firm greens, such as romaine or iceberg lettuce. Iceberg should keep for up to two weeks, romaine for about 10 days, and butterhead and leaf lettuces for about four days. Hydroponically grown butterhead lettuce with roots will stay fresh in the refrigerator for about a month if the roots are in water.
Don’t store lettuce near fruits like apples or bananas, which give off ethylene gas as they ripen. The gas causes the lettuce to develop brown spots and decay rapidly. For appetizingly crisp lettuce—and to minimize last-minute preparation at mealtime—wash and dry the leaves, then layer them in clean paper towels and place in a plastic bag. Refrigerate in the crisper drawer until serving time, but not for more than a few hours, for optimal nutrient retention. If you buy a cellophane-wrapped head of iceberg lettuce, leave it in the wrapper until you are ready to use it. Hydroponic lettuce should be left in its plastic package, and can be stored on any shelf in your refrigerator.
Published August 03, 2015