3 Simple Methods of Dehydrating Grapes for Raisins

Red raisins in bowl next to red grapes
You can dehydrate grapes for raisins in the sun, food dehydrator, or oven. To dry grapes in the oven or dehydrator, wash them and blanch them to break their skins. Dehydrate the fruits at 135°F for 18-48 hours in a dehydrator or 4 hours in the oven at 140°F. Dry unblanched grapes directly in the sun for at least 3 days.

How Do You Dehydrate Grapes for Raisins?

You can dehydrate grapes for raisins in the sun, in a food dehydrator, or in a conventional oven. The drying time differs with each method, but the quality of the dried fruit will be closely similar in flavor and degree of dryness.

Golden raisins being dried on the vine
Grapes being dried on the vine

Can You Put Grapes in a Food Dehydrator to Make Raisins?

Yes – grapes dehydrate into flavorful raisins when dried slowly in a food dehydrator. Here’s how to dehydrate grapes to make dehydrator raisins:

  1. Select ripe grapes. Seedless grapes like Thompson green grapes are the best for making raisins, but other types such as moon drops, cotton candy, and white, red, black, or purple grapes will work.
  2. Pluck the grapes from the stems.
  3. Wash grapes in a colander using cool running water to remove bloom and surface dirt.
  4. Break the skins of the grapes by blanching them in boiling water for 30 seconds and immediately submerging them in ice water to end the cooking process.
  5. Pat the grapes with paper towels to remove excess water droplets.
  6. Slice large grapes in half, with or without cutting all the way through, depending on your preference.
  7. Arrange the blanched grapes in a single layer on dehydrator trays with the skin side down.
  8. Load the dehydrator and dry the grapes at 135°F or the fruit setting for 18-48 hours until leathery. The drying time will depend on your dehydrator type, the number of fresh grapes, the area humidity, and the juiciness of the fruits.
  9. Monitor the dehydration process and flip the grapes every 8 hours to keep them from sticking to the trays.
  10. Test the drying grapes for doneness after 18 hours. Remove a few pieces and squeeze them. They should be leathery and have no moist center. It’s okay if they are firmer than store-bought raisins.
  11. Remove dried grapes from the dehydrator once dried and cool them to room temperature.
  12. Condition your homemade raisins for 7-10 days in large airtight containers. Shake the containers once daily and monitor them for stickiness and evidence of moisture or condensation inside the jars. Re-dehydrate the grapes with signs of moisture.
  13. Store all the fully dried grapes in airtight fruit containers like Mason jars and Mylar bags in a cool, dry, dark place.
Homemade raisins in a bowl
Homemade raisins

How to Dry Grapes for Raisins in an Oven

Dehydrating grapes in the oven is a faster way to produce homemade raisins. However, you must be careful not to overcook the fruit. Do it right the first time by following these steps:

  1. Prepare your fresh grapes by plucking them off the stems, washing them, and blanching them. Dab them with paper towels to absorb excess water. Cut the large ones lengthwise in half.
  2. Arrange the grapes with the skin side down in a single layer on a baking sheet lined with oiled parchment paper. You can brush a thin layer of cooking oil over the parchment paper to prevent sticking.
  3. Place the loaded baking sheet into the oven and dehydrate the grapes at 140°F or the lowest temperature setting, preferably no more than 170°F. Use an oven thermometer to monitor the real-time oven temperature.
  4. Leave the oven door 2-6 inches open for moisture removal and aeration. If you have multiple trays, place them 2-3 inches apart for aeration.
  5. Dry the grapes for 3-5 hours until leathery and check for dryness after 4 hours. Take out a few grapes and cool them to room temperature. Feel them by touch for leatheriness, and squeeze the center to check for evidence of moisture.
  6. Continue dehydrating in 15-minute increments if the grapes are not fully dried. The total time will depend on your oven, prevailing humidity, and the size and juiciness of the grapes.
  7. Once fully dried, remove all the grapes from the oven and condition them at room temperature for 7-10 days. Re-dehydrate any grapes that show signs of moisture.
  8. Store your successfully made raisins at room temperature in airtight containers in a cool, dry, dark place.

How to Sun Dry Grapes for Raisins

Sun-drying grapes may take longer than using a food dehydrator or oven, but it’s better because solar energy is free. Follow these steps to dehydrate grapes in the sun:

  1. Arrange washed grapes on a baking sheet.
  2. Cover the loaded baking sheet with a drying screen to avoid dust, bugs, and pets.
  3. Weigh the drying screen down with large spoons to keep it from shifting.
  4. Keep the baking sheet directly in the sun and dehydrate the grapes for at least three days. Bring the grapes indoors every night to prevent rehydration by night dew.
  5. Once all the grapes have dried to a leathery texture, bring them inside. Store the raisins in airtight containers and monitor them for condensation for a few days before long-term storage.
Large amount of grapes on straw, drying outside with a thin tarp over them
Drying grapes outside

Are Raisins Just Dehydrated Grapes?

Raisins are dehydrated grapes. The dehydration levels may differ between homemade and store-bought raisins, but they are all just dried grapes.

What are Grape Raisins?

Grape raisins are dried grapes. Raisins are classified as sultanas, currants, and black, green, golden, or red raisins.

Shot glass of raisins surrounded by green Thompson grapes
Thompson grapes and raisins

What are the Benefits of Dehydrating Grapes?

Dehydrating grapes offers convenience and the following health benefits:

  • Dehydrated grapes have a longer shelf life than fresh grapes.
  • Dehydration concentrates the nutrients in grapes into a small package.
  • Dehydration minimizes storage space requirements since the grapes shrink as they dry.
  • Dried grapes are rich in calcium, B vitamins, iron, dietary fiber, carbohydrates, and vitamin C.
  • Dried grapes are versatile healthy snacks, outdoor dried fruit, appetizers, and lunch treats.
  • Making raisins from your own raisins at home eliminates the possibility of consuming the preservatives that make raisins from the grocery store or supermarket last longer.
  • The laxative effect of dried grapes helps reduce constipation for a healthier digestive system.

How Many Raisins Are in a Cup?

One cup of 160 grams contains approximately 320 raisins. The USDA recommends a daily serving size of ¼ cup or 40 grams, roughly 80 raisins based on 0.5 grams weight per dried grape.

Since each grape shrinks about 4.63 times when dried, you would need roughly 742 grams of fresh grapes to make a 160-gram cup of raisins. The number of grapes in one cup depends on the size and weight of each fruit and how loosely or tightly they are packed.

A cup filled with golden raisins
A cup of raisins

How Long Do Dehydrated Grapes Last?

Dehydrated grapes have a shelf life of 1-2 years in a cool, dry, dark place. Homemade raisins must be properly conditioned and stored. The grapes will lose their texture and quality with time.

You can prolong the shelf life of your raisins by storing them with an oxygen absorber in airtight storage containers like glass jars, Mylar bags, Mason jars, and vacuum-sealed bags.

Alex Maina

Preserving food has become a meeting point for Alex's passions—gardening, cooking, and writing. Having grown up on a farm with cows, goats, chickens, and fresh fruits and vegetables, Alex knows the importance of preserving food for leaner times. He spends his time drying and canning foods, trying new recipes, and writing for Dehydrated Cookbook.

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