Editing Raisin (section)

==Processing==
[[File:Elaboració de pansa a Gata de Gorgos (Museu Valencià d'Etnologia).webm|thumb|Drying raisins at [[Gata de Gorgos]], Video by [[Valencian Museum of Ethnology]].]]

Raisins are produced commercially by drying harvested grape [[berry (botany)|berries]]. For a grape berry to dry, water inside the grape must be removed completely from the interior of the cells onto the surface of the grape where the water droplets can evaporate.<ref name="raisin processing">{{Cite journal | last1 = Esmaiili | first1 = M. | last2 = Sotudeh-Gharebagh | first2 = R. | last3 = Cronin | first3 = K. | last4 = Mousavi | first4 = M. A. E. | last5 = Rezazadeh | first5 = G. | title = Grape Drying: A Review | doi = 10.1080/87559120701418335 | journal = Food Reviews International | volume = 23 | issue = 3 | pages = 257 | year = 2007 | s2cid = 83652015 }}</ref> However, this diffusion process is very difficult because the grape skin contains wax in its cuticle, which prevents the water from passing through.<ref name="raisin processing" /> In addition to this, the physical and chemical mechanisms located on the outer layers of the grape are adapted to prevent water loss.<ref name="raisin production">Christensen, L.P., and Peacock, W.L. (20 April 2013) [http://iv.ucdavis.edu/files/24413.pdf "The Raisin Drying Process"] {{webarchive|url=https://web.archive.org/web/20130612192433/http://iv.ucdavis.edu/files/24413.pdf |date=12 June 2013 }}. ''Raisin Production Manual'', [[University of California]] at [[University of California, Davis|Davis]].</ref> The three steps to commercial raisin production include pre-treatment, drying, and post-drying processes.<ref name="raisin processing" />

===Pre-treatment===
Pre-treatment is a necessary step in raisin production to ensure the increased rate of water removal during the drying process.<ref name="raisin processing" /> A faster water removal rate decreases the rate of browning and helps to produce more desirable raisins.<ref name="raisin processing" /> The historical method of completing this process was developed in the Mediterranean and Asia Minor areas by using a dry emulsion cold dip made of [[potassium carbonate]] and ethyl esters of fatty acids.<ref name="raisin production" /> This dip was shown to increase the rate of water loss by two- to three-fold.<ref name="raisin production" />

Recently, new methods have been developed such as exposing the grapes to oil emulsions or dilute alkaline solutions. These methods can encourage water transfer to the outer surface of grapes which helps to increase the efficiency of the drying process.<ref name="raisin processing" />

===Drying===
[[File:Nearly Dried Raisins.jpg|thumb|Sun-dried raisins]]
The three types of drying methods are: sun drying, shade drying, and mechanical drying.<ref name="raisin processing" /> Sun drying is an inexpensive process; however, environmental contamination, insect infections, and microbial deterioration can occur and the resulting raisins are often of low quality. Additionally, sun drying is a slow process and may not produce the most desirable raisins.<ref name="raisin processing" />

Mechanical drying can be done in a safer and more controlled environment where rapid drying is guaranteed. One type of mechanical drying is to use [[microwave]] drying. Water molecules in the grapes absorb microwave energy resulting in rapid evaporation. Microwave drying produces puffed raisins.<ref name="raisin processing" />

===Post-drying processes===
After the drying process is complete, raisins are sent to processing plants where they are cleaned with water to remove any foreign objects that may have become embedded during the drying process.<ref name="raisin processing" /> Stems and off-grade raisins are also removed. The washing process may cause rehydration, so another drying step is completed after washing to ensure that the added moisture has been removed.<ref name="raisin processing" />

All steps in the production of raisins are very important in determining the quality of raisins. Sometimes sulfur dioxide is applied to raisins after the pre-treatment step and before drying to decrease the rate of browning caused by the reaction between polyphenol oxidase and phenolic compounds. Sulfur dioxide also helps to preserve flavor and prevent the loss of certain vitamins during the drying process.<ref name="raisin production" />
{{nutritional value
| name=Raisins, seedless
| kcal=299
| protein=3.3 g
| fat=0.25 g
| carbs=79.3 g
| fiber=4.5 g
| sugars=65.2 g
| calcium_mg=62
| iron_mg=1.8
| magnesium_mg=36
| phosphorus_mg=98
| potassium_mg=744
| sodium_mg=26
| zinc_mg=0.36
| copper_mg=0.27
| selenium_ug=0.6
| vitC_mg=2.3
| thiamin_mg=0.106
| riboflavin_mg=0.125
| niacin_mg=0.766
| pantothenic_mg=0.095
| vitB6_mg=0.174
| folate_ug=5
| choline_mg=11.1
| vitE_mg=0.12
| vitK_ug=3.5
| water=15.5 g
| note=[https://fdc.nal.usda.gov/fdc-app.html#/food-details/1102640/nutrients Link to USDA Database entry]
}}