We all know that the raisin is a dried grape, but did you know that there are a few different varieties? The most common are natural (the dark purple ones) and golden. But you may also come across seedless raisins, as well as those that are the crimson and flame variety, especially if shopping in an organic or gourmet market.
Most raisins are sold in boxes or resealable packages you cannot see through so it is difficult to judge freshness by the eye.
However, if you squeeze the box and it submits to the pressure, you can be sure the product is fresh. As raisins age, they dry out too much and will rattle around if the box or bag is shaken. So give the container a good shake and listen for any loud noises.
The natural raisin, made from the Thompson Seedless grape, is labeled "natural" because of how the grape is dried--simply by the sun, without any oils or solutions. Golden raisins are actually made from the same types of grapes used to make natural raisins but go through a different processing method, as well as a sulfur dioxide treatment, that gives these raisins their rich, golden hue.
It's important to properly store raisins so they don't dry out too quickly. Seal raisins in an airtight container or bag and store in a cool, dark place. Most kitchen cabinets are too warm. A month on the shelf is maximum, after which they begin to dry out, darken and lose vitamins.
Refrigeration is recommended for storage longer than a month, and in a properly sealed container, raisins can last six months to one year.
The high concentration of sugars in raisins are what make them sweet, but it is also what causes the raisins to become dried out and gritty, and stick to your teeth, after a long storage period.
The sugars can crystallize inside the fruit, but that does not mean you can't use them. There are a few ways you can revive dried-up raisins:
- Plump up the raisins by blanching them in hot water. Place raisins in boiling water for 10 to 15 minutes until they begin to expand. You can add citrus zest, spices or liquor to the water for extra flavor.
- Soften the raisins in the microwave. Place raisins in a bowl and drizzle with a few tablespoons of warm water. Microwave for 12 to 15 seconds, pour off any left over water and let sit, covered, to cool and absorb the moisture.
- Revive the raisins in the oven. Between layers of paper towels, spread the raisins on a cookie sheet and place in a 200 F oven for 20 to 25 minutes.
After reviving the raisins, they should be eaten, added to recipes or refrigerated on the same day. As raisins age, they may attract bugs, so be sure to examine them carefully for insect infestation before using.