Iceberg lettuce and leaf lettuces are popular choices for creating salads and as a sandwich addition or garnish.
Iceberg: More accurately called crisphead, this familiar pale green lettuce forms a tight, cabbage-like head. Its texture is crisp and its flavor very mild. Although it is not the nutritional powerhouse that other, darker-green lettuces are, it is actually not as nutrition-free as most people assume. There are also few substitutes in the lettuce world when you want a very crisp lettuce, as for chopped salads.
Romaine: Also called cos, this lettuce has long, deep green leaves that form a loaf-shaped head. Romaine, the main ingredient in Caesar salads, has a crisp texture and an assertive, but not bitter, taste.
Loose Leaf: This type of lettuce comprises a number of varieties that don't form heads, but consist of large, loosely packed leaves joined at a stem. The leaves are either green or shaded to deep red at the edges, and may be ruffled or smooth. Their taste is mild and delicate.
Care & Handling
Try to choose lettuce with healthy outer leaves; these are likely to be the most nutritious part of the green, containing much more beta-carotene and vitamin C than the pale inner leaves. Unfortunately, the outer leaves are usually the most damaged part of the head, but from a nutritional standpoint, it's best to salvage as many as you can.
Most lettuces and other greens keep best in a plastic bag in the refrigerator crisper. 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.
Leaf Lettuce must be washed--and in some cases trimmed--before you put them in the salad bowl.
Since grit tends to collect at the stem end of looser-headed greens, it's important to twist off the stem and separate the leaves before washing them. (If you're not using the entire lettuce at one meal, just remove as many leaves as you need from the stem.)
A salad spinner greatly simplifies the preparation of greens by drying them quickly and thoroughly. Dry leaves are a must if the dressing is to adhere properly.
Nutrition & Health Benefits:
Most leafy greens are good sources of vitamin C, beta-carotene, folate, and dietary fiber, as well as some calcium.