Considered one of the first fruits cultivated by humans, plums are the second most popular fruit in the world, with apples being the first.
Classified as a stone fruit, plums are related to peaches, apricots, cherries, and almonds, and the flesh surrounding the hard seed pit is the fruit that we enjoy. The flavors can range from sweet to tart, with the skin sometimes being particularly tart.
Technically, a “plum” is a fruit that does not easily separate from the pit (“clingstone”). It has a red, yellow, or green skin when ripe and is primarily enjoyed fresh. Varieties include beauty, shiro and Hollywood.
A “prune plum” is a specific plum variety that has a blue or purple skin when ripe, a higher fiber content and a flesh which easily separates from its pit (“freestone”). Typical uses for prune plums include dehydrating, juicing or cooked preparations. Varieties include Mirabelle, Seneca and Italian.
In the 1920s, prune plums were a major product in Clark County with more than 10 million pounds of prunes shipped annually throughout the U.S. and the world. Unfortunately, the 1929 Great Depression and an agricultural insect called “thrip” caused the demise of the industry. Today, there are only two remaining prune plum orchards in the area: Kunze Farm and Joe’s Place Farms.
When dehydrated, all plums are called dried plums. Prune juice is made from dehydrated plums, while plum juice is made directly from the fresh fruit. Prune and plum juices have distinctive flavors.
When selecting plums, choose those with smooth skins, free of cracks and bruises, and fairly firm. Tree-ripened fruit ensures proper texture, flavor and nutrition as the essential sugars develop in the final stage of tree ripening. Fruit harvested underripe to allow time for transportation can be bland and mealy. Locally sourced, tree-ripened fruit is definitely preferred for best flavor and texture.
If ripe plums are too firm, leave at room temperature for a couple of days to soften. To speed softening, place in a brown paper bag. Note that plums will not become any sweeter, only softer. Plums can be stored for three to four days in the refrigerator.
Wash plums just before using in cool running water. Briskly rub the surface of the fruit with your hands or a soft brush to remove of any debris or microorganisms on the fruit surface.
Room-temperature fruit offers best flavor.
Plums are a treat enjoyed fresh, but can be used in cooking and baking. Dehydrated plums make excellent snacks and great additions to baked products.
Plums are commonly canned or juiced but they also make tasty plum jams, preserves, conserves, spiced chutneys and barbecue sauces. Plums can be frozen for future fruit spread and sauce preparations. Plums also can be fermented to make wine and brandy.
One pound of plums (nine small, six medium or five large) equals 2 1/2 cups pitted and chopped or 2 cups cooked fruit. Four pounds of fresh plums produces 1 pound dried. A 16-ounce can contains 10 to 14 plums.
If preserving plums for future enjoyment, remember to use a tested, approved recipe and procedure to ensure food safety and best product quality.
For information and free downloadable how-to publications on canning, fruit spreads, sauces, pickling, freezing, and dehydrating, visit the WSU website http://ext100.wsu.edu/clark/?p=1134.
Leigh Rosenberger is a WSU Clark County Extension master food preserver. For more information, call the Master Food Preserver hotline at 360-697-6060, ext. 5366, or visit clark.wsu.edu.
