Plums are a juicy, sweet fruit with a thin skin and a large pit in the middle. They are related to apricots, peaches and nectarines. Plums are popular worldwide and are grown on every continent except Antarctica. Wild American plums were prized by Native Americans and were thought to be served at the first Thanksgiving. Today the United States and Chile are the main producers of plums for the rest of the world.
Varieties of Plums
There are several dozen species of plums that are categorized into European, Japanese, or American varieties.
- European plums (Prunica domestica) are thought to have originated thousands of years ago in the region around the Caspian Sea. They were brought to the United States by colonists and missionaries. Today they are grown mainly in California and the Pacific northwest. European plums are easily recognized by their deep blue or purple skin and yellow flesh. The plums tend to be oval or round and about three inches in diameter and have a freestone pit that is easy to separate from the flesh of the fruit. They are sweeter, firmer, and drier than the other varieties and are used mainly in cooking and to make prunes. Popular kinds of European plums include Italian plum, Damson, and Stanley. European plums generally reach supermarkets in August.
- The Japanese varieties (P. salicina) are actually native to China and were introduced to Japan several hundred years ago. They were transported to the United States by traders. Japanese plums have light to deep red skins (never purple) and their flesh is red to yellow. The plums are round and may have a small depression on one side and a pointed end at the other. The pits are clingstone, meaning they are much more difficult to pry from the flesh than freestone. The fruits are larger and juicier than the European varieties and are more commonly eaten raw than cooked. Their flavor is also more complex, ranging from sweet to tart to spicy. Popular kinds of Japanese plums include Santa Rosa, Kelsey, and Red Beauty. Japanese varieties are more commonly sold in American supermarkets and have an earlier season from June to September.
- The American plum varieties (P. americana) grow wild throughout the United States. They can be purple, red, orange, or yellow in color and are about one inch in diameter, smaller than the other two commercially grown types. They also have a wide range of juiciness and flavors and are mainly used in cooking. They are not commercially sold, although you may find them at local farmer's markets when they are in season or find a wild tree of your own.
Several varieties of plums are commonly crossed with apricots to yield plumcots. These plumcots can then be crossed again with an apricot to produce apriums or crossed with a plum to produce a pluot. These fruits tend to be sweeter and more flavorful than either of the parent fruits. While they are much rarer than plums or apricots, it is possible to find them in supermarkets.
Plum Plants
The plum plant varies in size from shrubs to medium sized trees. They are rather hardy and can grow in a wide variety of climates. They are more tolerant to frost than other fruit trees and therefore can be grown in almost all the 50 states. The plants produce clusters of white flowers in the spring. Plums ripen between May and October, depending on the region and variety. They are generally picked before they are fully ripe to avoid bruising during transport.
Buying and Using Plums
When shopping for plums, look for fruits that are somewhat soft and unbruised. Plums bruise very easily and should be handled carefully. The plums may have a faint white dusting which is just harmless bloom. Firm fruits can be ripened by placing them in a paper bag for several days, but they will not become sweeter or more flavorful, just softer. Ripe fruit will keep in the fridge for several days. The most flavorful kinds of plums will be in supermarkets from June until September. Plums varieties available earlier in May or later in October are not as sweet.
Japanese types are the best to eat raw while European types are drier and more suited for cooking. To cut a European plum, make one slice all around the pit, twist to separate the halves, and remove the pit. It is more difficult to cut a Japanese plum because of the clingstone pit. To cut one, slice segments out of the plum like a melon, avoiding the pit. The plum's skin can be removed by peeling or blanching, but it adds flavor and color to the cooked dish. Fresh plums make wonderful pies, tarts, and cobblers. Plums can and freeze well and can be made into preserves and chutneys. They also are good in stews and curries with savory meats.
Many plums are commonly dried to make prunes. However, only European varieties are used, as they contain a high level of sugar which ensures that the prunes will be sweet. The French Agen is the most famous variety of prune and is made from Ente plums that were first grown in the French shipping town of Agen. Recently, the prune industry has renamed prunes as "dried plums", apparently to give them a more youthful appeal. Prune juice made from semi-dried plums can also be purchased.
The Joy of Cooking, revised edition, 1997.
http://www.wholehealthmd.com/refshelf/foods_view/1,1523,65,00.html
http://www.psgrill.net/Food/FoodInfo/Fruits/Deciduous/plums.html
http://www.uga.edu/fruit/plum.htm
http://www.tonytantillo.com/fruits/plums.html