Drying foods in the open air with the warmth of the sun is humankind's oldest preservation method. Lucky for us, we now have the convenience of the oven! Oven drying is one of the many dehydration processes found in Canning & Preserving Your Own Harvest, An Encyclopedia of Country Living Guide. Turn on your oven and try out the recipe for Oven-Dried Tomatoes (or as I call them, Christmas gifts for all my relatives).
This is an effective method for drying small batches laid out on a wire cooling rack on a sheet pan. The challenge with oven drying is maintaining a low, steady temperature of 120 to 150°F. Warmer than that and food will cook, not dry. A reliable oven thermometer placed at the rear of your top tray will help gauge the proper heat setting. Prop the oven door open to promote good air circulation; if you have a convection oven with an internal fan, be sure that the fan will work with the door open.
Small jars of dried tomatoes packed in oil are costly deli items. Preparing your own when the summer crop is abundant is easy and every bit as tasty.
Season: Late summer through fall
Yield: 1 pint
Store: Refrigerator or cool, dark pantry
4 pounds ripe but not overly soft Italian paste-type
(plum, Roma) tomatoes
1 sprig fresh rosemary
Preheat oven to 200°F. Line sheet pans with foil or parchment paper and set cooling racks on them. Halve the small tomatoes and quarter the larger ones, removing the tough core at the stem end. Gently squeeze the tomatoes to remove most of the seeds.
Arrange the tomatoes, cut sides up, on the cooling racks. Sprinkle them lightly with salt. Place pans in the oven and prop the door open to allow moisture to escape; a convection oven with a built-in fan is ideal. The tomatoes are done when they have shriveled and are leathery but not brittle. Their color should be a deep ruby red. The amount of time required will depend on the tomatoes, but count on 6 to 8 hours.
Cool the tomatoes completely. Place them in a bowl and sprinkle with vinegar, tossing with your hands to lightly moisten them. With a slotted spoon, remove the tomatoes and drain on paper toweling, patting them to thoroughly dry.
Pack the tomatoes into a sterilized pint jar together with the rosemary. Pour in enough olive oil to completely cover the tomatoes and cap securely. Store at cool room temperature for 1 month before serving. Refrigerate after opening.
A Tip for Drying Vegetables
To avoid increasing water content, vegetables should be steam blanched before drying, to preserve nutrients and color. Drain thoroughly and pat dry with towels to remove all surface water. You do not need to blanch chili peppers, onions, celery, zucchini slices, thinly sliced mushrooms, and garlic.