Dehydrating (drying) tomatoes is easy to do, requires little skill or equipment, and produces very satisfactory results. You can dry tomatoes in a food dehydrator, in an oven or in the sun (if you have sufficient steady sunshine). Dried tomatoes are great for cooking; the dried 'maters will re-hydrate in liquid, like soups or stews, and the intense tomato flavor is a great bonus when used dry for breads and salads because the tomato flavor is concentrated when the water is removed.
Also, dried tomatoes store very compactly for long periods if you vacuum seal them into pouches. If thoroughly dried, they can be kept in your pantry or in a decorative jar on your kitchen counter.
For drying, you will want firm, meaty tomatoes, not the juicier ones like beefsteak. Romas are an excellent choice, as are small Best Boy and Lemon Boy tomatoes. Freeze the big ones, dry the small ones. Before dehydrating, wash, dry, remove the cores and cut your tomatoes. There is no hard and fast rule on how to cut tomatoes for drying; some like wedges, some like slices, some like halves. Mostly it seems to depend on the size of your tomatoes. Cherry tomatoes, plumb tomatoes and even Romas, do well as halves because of their small size. Anything larger dries faster and with fewer hassles as wedges. ¼ to ½ inch thick slices dry the fastest, but will wither up to practically nothing in the process. Use the same "equatorial cut" I described in Freezing Tomatoes and clean out the wet, seedy goop with a spoon or paring knife to speed proper drying… except with cherry tomatoes, it's not worth the bother on them; just cut them in half. Regardless of the drying method you use, place the tomatoes skin side down while drying. Refrigerate them if you must stop the dehydration process for the night or if you must leave the house for an extended period.
Using Solar Power
To sun dry tomatoes, first prepare your "rack"; a piece of plywood works well, cover it with Saran Wrap and tape that to the wood around the edges. Cut your tomatoes and arrange them on the rack. Slices work best for sun drying. Sprinkling with salt will hasten drying by absorbing some liquid, but this is optional. Set the rack in a secure location that will get the maximum amount of direct sunshine. Do what you can to keep bugs away until they "skin over" at that point the bugs seem to lose interest. This will take 18 to 24 hours of strong sunshine, so you will need to plan on setting them out for several consecutive days. Refrigerate them between sessions. This method won’t work well for us here in the mountains of Tennessee; folks in Texas, Arizona or California would have better luck with it.
To dry in a regular oven, spray a rack (could be an oven rack or a special drying rack) with cooking spray or rub with olive oil to prevent sticking. Cut and clean your tomatoes and arrange on the rack(s) skin side down. Place the rack(s) in the oven and set the temperature to 135°. Anything below 120° promotes bacteria growth; anything above 145° can scorch your 'maters. Prop the door open a little to allow moisture to escape. It will take 12-15 hours to dry larger cuts this way, keep an eye on them and remove the ones that are done as they get there, differences in size, shape and moisture content will cause variance in this. This method works well, but tends to heat up the house quite a bit. I cannot find anything on the use of a convection oven, but I should think that if the oven vents moisture, it would be even more effective. If not, you will still have to prop the door open. Do not dry tomatoes in a microwave. Trust me on this, just don't do it. Really.
In many ways using a food dehydrator is the easiest way to go - if you have access to one. Even if you don't own one, someone you know might: ask around. I borrowed my Mom's. We really don't have room to store such a large contraption in our kitchen, and she doesn't use it very much, so borrowing hers works well for both of us because I will share the product of my labors as "rent". Spray the racks of your dehydrator with cooking spray or rub with olive oil and arrange the tomato pieces on the racks so they are not touching. If yours has fan speed and temperature controls, set them on low and 135°. It will take up to 15 hours to complete, check them occasionally and remove those that have finished drying. Slip the racks in the fridge if you must stop for the night so they don’t start to mold.
How Dry is Dry Enough?
You may go two routes: leather-like or crispy-dry. Crispy dry will last longer in storage and can be easily crushed if you desire. Leather-dry means there are no moist pockets left and the tomato does not stick to your finger when you poke it, but it is not dried hard. The danger is that if moisture is left in leather-dry tomatoes they will mold. Refrigeration slows this down but does not prevent it. Vacuum packing will also extend their life in the fridge. Since we intend to store these for the winter, I’ve been drying mine to the crispy-dry state and vacuum packing them using our Food Saver machine. Using this method I can store about 10 pounds of whole tomatoes in one quart-sized vacuum bag. Theoretically, these can be stored in the pantry, but we’ll put them in the fridge just the same.
Uses for Dried Tomatoes
For use in most cooking, dried tomatoes will need to be re-hydrated by soaking in water for around two hours. More if they are crispy-dry, less if you use boiling water. Dried cherry tomatoes can be added to homemade bread dough or sprinkled on a salad for a flavorful punch. We’ve found we like “tomato chips” made from halved tomatoes just as a snack. A particularly gourmet way to store dried tomatoes is to layer them into a decorative jar with seasonings and cover them with extra virgin olive oil. When the tomatoes are gone, use the seasoned oil in your cooking.
I made several jars of dried tomatoes in olive oil – and botched them badly. I believe the mistakes I made were: The dried tomatoes will absorb the oil and expand, therefore you must not fill the jars with tomatoes, but leave room for this expansion and add oil as needed to keep them covered. I filled the jars with tomatoes layered with fresh basil, oregano and thyme from our garden. They looked beautiful, but began to push oil out the top of the jar in short order, making quite a mess! I transferred them to larger (less attractive) jars. It was my impression from the several articles I used to research this tomatoes-in-oil thing that they could be used as a decorative touch on the counter. I did not refrigerate my tomatoes in oil and those on top of the jar molded, necessitating disposal. I’m not sure if I didn’t dry them enough, or didn’t keep them covered with the oil or if refrigeration is required despite the many photos of decorative jars sitting on counters. One of the folks who drop by The Prattle from time to time is Aussie Sire; and he’s an old hand at making these, perhaps he will favor us with an explanation of what I did wrong on his next visit.
What About You?
Have you tried drying tomatoes? Do you have a favorite use for dried tomatoes? Do you have any tips to share? Please join in through the comments below. Thanks for reading!