Where Do Raisins Come From?
Special varieties of grapes are dried, and are then called “raisins”, the French word for grapes. Until the 20th Century they were produced mainly in the Mediterranean regions. Now huge quantities come from California and Australia. Naturally produced raisins are spread out on trays and dried in the sun to a grayish brown color. They have a tough skin and sometimes keep the bloom—the bluish powdery coating—found on grapes.
But most of the raisins grown commercially are dried quickly in heated sheds and treated with sulphur to preserve them. These are usually small and dry and are used in cakes and puddings. One type of raisin which is particularly good to eat is called the muscatel. These raisins are grown near Malaga in the south of Spain, and are dried in bunches partly while still on vine and partly after picking.
Raisin varieties depend on the type of grape used, and are made in a variety of sizes and colors including green, black, brown, blue, purple, and yellow. Seedless varieties include the sultana (the common American type is known as Thompson Seedless in the USA), the Greek currants (black corinthian raisins, Vitis vinifera L. var. Apyrena) and Flame grapes. Raisins are traditionally sun-dried, but may also be water-dipped and artificially dehydrated.
“Golden raisins” are treated with sulfur dioxide after drying to give them their golden color. Black Corinth or Zante currant are miniature, sometimes seedless raisins that are much darker and have a tart, tangy flavor. They are often called currants. Muscat raisins are large compared to other varieties, and also sweeter. Several varieties of raisins produced in Asia are available in the West only at ethnic grocers. Monukka grapes are used for some of these.
How Are California Raisins Made?
Natural seedless raisins are dried by the sun, and then loaded into bins for delivery to the processing plants. The raisins can either be dried on paper trays on the ground between vineyard rows or dried on the vine, and mechanically harvested once the desired level of dryness is achieved. Before they are unloaded from their bins, government inspectors take long prods to gather samples from the middle of each box.
United States Department of Agriculture (USDA) inspectors examine incoming fruit to ensure that each box meets incoming fruit guidelines. Next, raisins are cleaned, which means they go through a series of conveyor belts and drums to remove remaining stems, chaff or lightweight fruit. The raisins also are sent through a vacuum air stream to catch any other undesirable materials. Finally, they’re size-graded and thoroughly washed in pure water.
In preparation for packaging, the raisins are moved through a laser sorter where the sorter’s light beams, along with a computer, to see if anything beside raisins is passing through the stream. If material other than a raisin is present, the computer sends a burst of air to knock it out of the stream of raisins and down a trough.
California Raisins are inspected under the most rigid standards by both plant quality control technicians and USDA inspectors throughout the packaging process, thus assuring that California Raisins are the cleanest, highest quality in the world. After final inspections, raisins are automatically weighed and packed in a variety of bulk industrial and convenient retail sizes. California Raisins are then shipped throughout North America and the world for consumers to enjoy.
Part of the crop is used to make raisin juice concentrate (a minimum of 70 percent natural fruit soluble solids) and raisin paste (made from 100 percent raisins), which are added to a variety of foods, including dairy, confectionery and bakery items.