Why Don’t Tomatoes and Fruits Rot When They’re Sun-Dried?
Why don’t tomatoes, apricots, raisins, and other fruits rot when they’re sun-dried? The high concentration of sugars in dried fruit prevents bacterial growth, but the trick is getting the fruit dry before mold can grow. Even under optimal hot-and-dry conditions, like those of Central California or the Mediterranean, it takes four to six days to sun-dry tomatoes and two days or longer for stone fruits, says Paul Walker, director of sales for Traina Foods, growers and driers of apricots, peaches, nectarines, cherries, plums, pears, and tomatoes. The vast majority of sun-dried fruits are preserved with artificial chemicals. The most common of these are sulfites, which prevent bacterial growth and preserve color by absorbing oxygen, and also keep insects away from the drying fruit. The only common sun-dried fruits not preserved with sulfites are dark raisins—they’re small enough to dry before rot takes hold, Walker says. Their color is a natural result of oxidation; golden raisins come fro
