Boston lettuce, also known by the names Tom Thumb, Bibb, Butter and Buttercrunch, is one of six types of lettuces generally available for human consumption throughout the world. It is a member of the butterhead family, so-named based on the velvety, butter-like texture of the leaves, particularly those at the heart or internal center of the head. First popularized in Europe, it is now commonly available in many supermarkets worldwide.
The two most popular varieties of lettuce in North America are Boston and Bibb. Bibb lettuce has leaves that are narrower and darker green than Boston lettuce. It was developed by John Bibb, a Kentucky farmer, as a hybrid of Boston lettuce in the mid 1800s. Both of these varieties are frequently sold, especially in health food markets, with the roots attached to them to preserve freshness. The appearance of both lettuce types resembles a blooming rose, with soft leaves that part like rose petals.
This type of lettuce is rich in vitamins K, B, C and A and is an excellent source of sodium, calcium, potassium and magnesium. Boston lettuce also contains significant levels of lactucarium, which affects the human physiology much like opium. Based on these tranquilizing effects, Boston lettuce is sometimes recommended as a natural treatment for heart palpitations, spasms of the intestines and insomnia.
Based on its fragility and tendency to quickly grow limp when handled or left unrefrigerated, it is generally recommended that Boston lettuce be stored in a lightly perforated bag in the vegetable drawer of the refrigerator, with the humidity dial turned to a moderate setting. It is normally suggested that the lettuce be washed and dried immediately before serving. Boston lettuce’s large, pliable leaves make it a popular wrap for appetizers and hors d’oeuvres, and it is frequently paired with fruits and creamy cheeses.
There are five other types of lettuce grown as food products worldwide. They all have different properties that make them appropriate for a variety of dishes. Chinese lettuce has sturdy leaves and stems that hold up well in stir-fry cooking. Crisphead lettuce, commonly called iceberg lettuce, is so-named based on its high water content and crunchy texture. Heads of iceberg lettuce often closely resemble heads of green cabbage.
The variety called looseleaf looks much like arugula. It has tender stems and fragile leaves that impart a mild flavor. Romaine lettuce, also regularly referred to as Cos, is a long, lanky lettuce that has a sturdy middle rib and large, ruffled leaves. Summer Crisp lettuce, sometimes labeled Batavian, is a pleasant cross between iceberg and looseleaf. Its head is moderately dense, with tender leaves that have a mild crunchy texture.