Imported Raisins -
The principal types are Malagas, or Muscatels, Valencias and Sultanas.
Raisins" synonym2="muscatel Raisins">Malagas, or Muscatels, the finest grade, are prepared by partly cutting through the stalks of the grape bunches and allowing them to dry as far as possible on the vine. grapes">Valencias are dried after being taken from the vine, either in the sun or in ovens. In both cases the fruit is next dipped in an alkali solution, which slightly cracks the skins, and then washed, laid on benches to drain and dried in the sun (when possible) for two weeks. The Raisins are then ready for packing - in casks, boxes, cartons, etc. They vary in quality from the best "cluster" and "layer" to the cheapest "loose" Raisins. "Layer Raisins" are those of fine quality, packed in bunches between sheets of paper. "Cluster" signifies "bunch."
Lexias is a term sometimes applied to Raisins more suitable for cooking than dessert use.
Sultana Raisins, or "Sultanas" as they are generally styled, are small, oval, naturally entirely seedless, and, in the best grades, of a pale yellow transparent tint. They come from Smyrna, but there seems to be no essential difference between the vine which yields them and the ordinary grapevine - the special characteristic of seedlessness may have been produced by exceptional circumstances of soil and climate, leading to partly abortive flowers.
Corinthian Raisins is another name for CURRANTS (which see).
Arround Imported Raisins in The Grocer's Encyclopedia