Did you know that in California, where weather conditions are optimal for vineyards, grapes are dried by being placed in the sun? They produce natural seedless raisins, mostly made from Thompson Seedless varieties. In Turkey, before sun drying, grapes are treated with a dipping solution, which aims to increase the permeability of the wax layer of the berries to water and quicken drying(1).
As the home of the Sultanina variety, Turkey is the leading supplier of Sultana raisins. Other major dried grape producing countries include USA, Iran, China and India. The most common dried grape varieties are Sultanina (synonyms Sultana, Thompson Seedless) and Currants (Black Corinth and Zante currant).
Bites of Health
Raisins are high in potassium, which contributes to the maintenance of normal blood pressure(2). Scientific studies have also seen an association between eating raisins and lower blood pressure. Not only that, raisins are a low-to-moderate-glycemic-index food (an indication of their effect on blood sugar level), which may help in the prevention of type 2 diabetes(3).
Facts and Figures
The origin of the word raisin is the Latin ‘racemes’, which means a “cluster of grapes or berries "(4). cultivated by the anatolian and Egyptians since ancient times, grapes were prized for their sweetness and wine production. Legend has it that Noah became the first viticulturist after seeing a male goat becoming cheerful after eating grapes.
 Resolution OIV-VITI 522-2016. OIV Good Practises for Dried Grape Production Systems: http://www.oiv.int/public/medias/4956/oiv-viti-522-2016-en.pdf.
 Anderson JW et al. Raisins compared with other snack effects on glycemia and blood pressure: a randomized, controlled trial. Postgrad Med. 2014 Jan;126(1):37-43.
 Anderson JW et al. Raisin consumption by humans: effects on glycemia and insulinemia and cardiovascular risk factors. J Food Sci. 2013 Jun;78 Suppl 1:A11-7.
 California Raisins Advertising History & Fun Facts. http://calraisins.org/california-raisins-advertising-history-fun-facts/