Introduction
(Pistum sativum ssp. sativum -- Family Leguminosae)
Peas are an ancient staple originating in western Asia. There are three main kinds: the familiar garden pea (Pistum sativum ssp. sativum), the field or gray pea (P. sativum ssp arvense, formerly P. arvense) grown mainly as fodder, and the small, wild Mediterranean pea (ssp. elatius), also known as the oasis or maquis pea. Other commonly called "peas" are legumes of different genera.
The earliest records are of smooth-skinned types found in Mediterranean and European excavations dating from 7000 BCE. Remnants were also found in relics of Bronze Age settlements in Switzerland, dating from around 3000 BCE, as well as in predynastic Egyptian tombs, in ruins of Troy, and in buried caves in Hungary. The Greeks and Romans cultivated and ate them in abundance, and it was the Romans who introduced them to Britain. They were also likely responsible for its spread through India, where it is still a popular vegetable. However, it appears that peas did not reach China until the 7th century CE, where they were given the name hu tou, meaning foreign legume.
In classical Greece, peas were known as 'pison', which was translated into English as 'peason'. By the time of Charles I, they became known as pease; and, by the 18th century, this was shortened to "pea". During the reign of Elizabeth I, various types were imported from Holland. The traditional English "pease pudding" is made from dried peas and was a versatile food as referred to in the popular nursery rhyme. Peas were generally eaten dried or ground until the 16th century, when Italian gardeners developed tender varieties for cooking and eating fresh, although it took another century before this practice was accepted by the wealthy and fashionable English. Peas were not eaten fresh until the 17th century, when Louis XIV developed a liking for them. Peas were a favourite vegetable of Thomas Jefferson, who held the annual competition among his friends to see who could grow the first peas of the season. The winner had the privilege of inviting other group members to dinner to celebrating their arrival. Invitations were issued saying "Come tonight, the peas are ready".
As peas age, they convert their sugar to starch; and, within a few hours after picking, as much as 40% of the sugars will be converted. Sugar peas should be eaten immediately after picking, and are eaten as immature pods. It takes about one pound of unshelled green peas to yield one cup of shelled peas. Fresh peas are a moderately good source of the food fiber of pectins, gums, hemicellulose, cellulose, and the noncarbohydrate food fiber lignin. Peas are also high in incomplete proteins, lacking only tryptophan, methionine, and cystine; but, by combining them with grains, the proteins are made complete. Peas are also an excellent source of vitamin A, which comes from the yellow carotenoids hidden under the green chlorophyll. As peas age, their chlorophyll fades and the yellow pigments begin to show through.
Peas are also a good source of vitamins C, E, B complex, iron, and magnesium. Snow peas and sugar snap peas supply about half the fiber but much more vitamin C than green peas, which are also an excellent source of Vitamin B6. Peas and other legumes are a good choice for diabetics as they help regulate the flow of blood sugar. Fresh peas are generally one of the most digestible and non-gassy of the legumes and have a mild diuretic and laxative effect. Instead of throwing out the pods after shelling, store them in the freezer until the next time a soup stock is needed. They can be leeched of their nutrients at that time.
Green split peas are one of the oldest of vegetables, but early varieties were quite starchy even when young. Both the Greeks and the Romans cultivated shelling peas for drying. When the peas are split, cooking time is much less. They are sometimes found in the whole, dried form but they take much longer to cook. Yellow split peas are a favourite of the French Canadians living in Quebec, as well as in India and Sweden. Thursday night is the traditional time for Swedes to make thick, yellow split pea suppers to commemorate the death of King Eric XIV, who was poisoned when arsenic was put in his yellow split pea soup. In India, the yellow split peas are sometimes roasted, ground, then used as a binder or thickener in foods.
Today, however, peas are cultivated in almost every country in the world. The largest producers are the US, Europe, and India, and cultivated almost exclusively out of doors, but only about 5% are ever marketed fresh. The vast majority is processed by the food industry in such forms as canned, frozen, and dried. At the end of the 19th century when canned vegetables began to be widely sold, peas were a popular item. When canned, however, they turned them a dull khaki colour as their chlorophyll was destroyed by heat. To counteract this, processors turned to dying them a bright green. Even though processing has come a long way since then, the canned pea bears little resemblance to the fresh interms of nutrition and taste, and may almost be considered a separate food item. Processed peas are treated with alkali to make them soft and starchy. The term "garden pea" is used to distinguish the fresh from the processed. Freezing peas, which began in the 1920s became a preferred method of processing as they retain much of their attractive qualities, including nutritive value.
There are only two varieties of plant in terms of growing habits. These are the low-growing and climbing peas, which can reach heights of over six feet. In seed catalogues, peas are usually listed according to the timing of the crop, early, second early maincrop, and maincrop types. However, some descriptions may refer to the pea itself or to the pod. Earlier varieties are lower growing than later ones, which are taller and higher yielding. Petits pois are small with a good flavour. They are a dwarf variety of pea, not ones harvested prematurely. Semi-leafless varieties have more tendrils than leaves, becoming intertwined and self-supporting as they grow. One unusual pea is the Marrowfat Pea, an old English variety thought to taste as good and rich as the marrow fat enjoyed in such dishes as osso buco.
Commercially, peas are classified as wrinkled, round, smooth, or having edible pods.
-- Round-seeded types (convar. sativum) are easily recognized by their smooth, round yellow or green seeds. The tough, green pods are harvested while the seeds are still small and tender. They are often dried when fully ripe, and, because of their high starch content, taste slightly mealy and less sweet than wrinkled or sugar snap peas.
-- Smooth-seeded types are hardy and are used for early and late crops.
-- Wrinkle-seeded varieties (convar. medullare) are less hardy and generally sweeter. They are a type of pea that is particularly large, sweet, and tender and do not become soft when cooked, but sold only as a fresh vegetable. Tall Telephone is a wrinkled type of marrow pea which grows on eight foot vines with pods that hang straight down. It is also known as Dwarf Telephone pea, Alderman pea, and Carter's Daisy pea.
There are differences between green peas, snow peas, and sugar snap peas. Green peas are the garden pea hidden within a large, green pod. Generally, the pod is discarded after the peas are removed; but some young tender varieties have an edible pod, which are often used in Chinese dishes. Green peas are highly perishable and the sugar to starch conversion begins the moment they are picked. Snow peas have flat, tender pods three to four inches long that protects tiny, immature peas inside. Both the peas and the pod are edible and the colour is a bright green. Sugar snap peas are totally edible and are a combination of the green and snow peas. Like green peas, they are slightly tubular, but a little smaller. The pods are thicker than snow peas, but more delicate than the green. The peas inside are more developed than the snow peas. Both snow peas and sugar snap peas last much longer than the green pea.
