Drying is an ancient culinary technique that historians have traced back to caveman times. Since the invention of the refrigerator was several thousand years in the future, drying meat was the only way early man could keep food from going bad before they could eat it. And by drying strips of meat in the baking sun -- letting 80 to 90 percent of the water content to evaporate -- it was much easier for our ancestors to travel with a lighter and smaller cache of food.
Not much has changed about t…
e process and purpose of drying food. What has evolved are the tools we use for drying. We also know more about food safety and preventing bacteria from growing on food while it's drying. Food drying is something you can do along with canning and freezing, or instead of these other methods of food preservation.
There are primarily three common drying methods you can do at home, ranging from the old school (free, outdoor sun exposure) to state of the art (buy a food dehydrator). Oven drying is more sophisticated than doing it outdoors, but it's not as reliable as a dehydrator.
Sun drying is the most low-tech drying method. You don't need any special equipment, but you do need the cooperation of Mother Nature. The best way to do it right is by checking your local weather forecast and finding several consecutive 85-degree-F days, preferably with humidity no higher than 60 percent. Oven drying is much easier than outdoor drying, but you still need to monitor the food during the drying process. You can dry almost anything in the oven. For some types of food, you can even use a toaster oven. Food dehydrators are for drying hobbyists. These appliances are easy to use, they don't take up a lot of space on the counter or in the pantry, and they're not expensive.
Sun drying works best in locations where the weather is reliably hot and dry over the course of several days in a row. If you're expecting some rain showers at night, that's OK as long as you're going to have long, hot sunny days.
Here are instructions for making sun-dried tomatoes. Paste tomatoes (including plum tomatoes) are ideal for drying. But almost any kind of tomato can be dried. Your drying station should be over a patch of concrete, over bricks, or a wood patio. If you try to dry food over grass, and the land happens to be moist from rain or dew, drying could take a lot longer. At worst, the conditions will be too humid for drying, and you just sacrificed a bushel of fruit or vegetables and the time it took to prepare it for drying.
Place food on a rack that's elevated off the ground by several inches. Air should be able to circulate over and under the drying food easily. Place a sheet of aluminum foil on the ground (or on the bricks) to reflect the sun's heat and rays onto the bottom of the food that's on the drying rack.
- Slice tomatoes, lengthwise, in half or in thirds
- Sprinkle chopped herbs and sea salt onto the tomato slices
- Lay tomato slices on the rack
- Keep insects away by covering the tomatoes with cheesecloth or a mesh screen
- Leave the tomatoes outdoors until nearly all the moisture evaporates, and the dried tomatoes look like a plump raisin
- The drying process can take several days. It's OK to leave the tomatoes out at night, but you will need to provide protection from insects, animals, and also shield the food from humidity or any unplanned showers.
Once the tomatoes are finished drying, you can stash them in a vacuum-sealed bag in the refrigerator or freezer. Or seal them in a canning jar with olive oil and put in the pantry.
Is the weather being uncooperative? You can always finish the drying process in the oven. Or if the mercury keeps threatening to dip into the low 80s or lower, there's a cool hack for that.
Do you know how hot your car gets when it's been sitting in direct sunlight? If the weather is a breezy 70 degrees, inside the car can still hit a blistering 100-degrees F. That's precisely the kind of environment that you need to dry fruit and vegetables.
Outdoor & Sun Drying Equipment
Keep insects and animals away from your food by covering it with a food-safe screen. Use screens made with stainless steel, fiberglass, plastic, or coated with Teflon. Don't use metal-coated screens, like copper, aluminum, zinc, or cadmium. Some metals can leave a harmful residue on food, they can destroy vitamins, or the metals can break down. To keep birds from flying off with pieces of fruit and vegetables, double the layers of screen or cheesecloth and fasten down the corners with heavy bricks or a staple gun.
When drying freshly harvested herbs, you can use kitchen twine to tie into bunches, then secure the ends of the string to a horizontal bar or a clothes hanger you can hang from a fence or railing. Herbs are very delicate and can burn easily in the sun. So hang them upside from a string inside a paper bag. Using a paper bag will catch that seeds that you can plant.
Oven drying fruit and vegetables is a lengthy process, but just a fraction of the time it takes to dry food outside. You also don't have to plan for rain or cold weather. First, select ripe fruit, berries, or vegetables and remove stems, pits, and entire fruits and vegetables that have blemishes. There's no hard and fast rule for how thinly you should slice food that you're drying, but a good rule of thumb is slicing them into a single, uniform size so that you don't have to pick out small pieces that finish drying sooner than thicker slices. Removing the skin is optional. But some types of fruit, like peaches and apples, actually dry better when peeled.
Preheat the oven. In general, the temperature for drying fruit and vegetables should be between 130-degrees F to 160 degrees F. The thinner the slices, the lower the temperature should be. You can stop the fruit from browning by washing slices in a solution of 1/4 cup lemon juice and 1 quart of water.
Oven Dried Fruit Chart
- Temperature 130-degrees F to 160-degrees F: 6 hours
- Plumbs, pears, peaches, bananas, apples: 8 to 10 hours
- Grapes, citrus peel: 12 hours
Oven Dried Apples Recipe
Preheat oven to 140-degrees F (for thick slices of apple, up the temperature to about 150-degrees F). Cover the sheet pan with parchment paper and arrange apple slices in a single layer. Do not let apples touch or overlap. To keep the fruit from curling, you can place a screen or silicone baking liner over the slices. Keep the air in the oven circulating better by rotating the baking pan every two hours. It might take drying a batch or two before you settle on a temperature in your oven that works best. But until then, drying experts suggest setting the temperature on your oven to the lowest setting (140-degrees or 150-degrees F), and leave the oven door propped open about three inches. If you have a convection oven with a setting for drying food, it may have a latch that prevents the oven door from shutting all the way.
Oven Drying Tips
If you have a newer oven, you may have noticed that the lowest temperature setting is 170-degrees F. Don't panic! One solution is to see if your countertop toaster or convection oven has a lower temperature setting. If not, then cut the fruit and vegetables into thicker slices. For your first try at drying, be sure to take notes on slice sizes, oven temperature, and how long a drying session takes. This information will help you hone in on proper slice size and oven temperature for your other drying recipes.
When it comes to convenience and reliability, you can't go wrong with the appliance that was designed specifically for dehydrating fruit, vegetables, herbs, and meat. These gadgets come with drying instructions and time and temperature settings for drying different types of food. You don't even have to rotate the food inside a food dehydrator because they're designed like a convection oven in that the heat circulates within the chamber and hits the food from all angles.