Pretreament for Fruit Dehydration

Question: Can you tell me what I should dip or soak fruit in before I dry it in my dehydrator?

Answer: According to the Master Food Preserver Manual of the University of California Cooperative Extension Common Ground Garden Program, “To prevent darkening and loss of Vitamin C, most fruits need pretreatment before drying. Sulfuring is the preferred pretreatment. Blanching in steam or in boiling water is an alternate pretreatment.

“Sulfuring--exposing fruit to sulfur fumes--helps preserve color and retain Vitamin C and makes a more pliable product due to retention of additional moisture. Sulfuring does cause a considerable loss of thiamine. Because fruits are a major source of Vitamin C but contain little thiamine, the overall nutritional effect of sulfuring is positive. Blanching gives a darker, less nutritious product than does sulfuring.”

The guide does warn, however: “Never dry sulfured fruits in the oven because of the objectionable odor of sulfur fumes.”

Complete instructions for sulfuring fruit are given in leaflet 2785, “Drying Foods at Home” available for $1.75 from ANR Publications, University of California, 6701 San Pablo Ave., Oakland, Calif. 94608-1239.

Q: What is the difference between fresh and dry bread crumbs? And how is each type made?

A: According to “How Cooking Works” (Macmillan, 1981) by Sylvia Rosenthal and Fran Shinagel, “Both fresh and dry crumbs are made by processing or blending bread in a food processor or blender until fine. Fresh bread crumbs are made from fresh bread that is slightly dried out. If the bread is too fresh, the crumbs may be gummy. Bread that is two to four days old is generally satisfactory. Don’t use stale bread, for stale bread will give you stale-tasting crumbs. For dry bread crumbs, crisp the bread on a baking sheet in a 250-degree oven. Some or all of the crusts may be used for either the fresh or the dry crumbs. Cut the bread into cubes before processing or blending.

“Store the crumbs in a tightly closed plastic bag or covered container in the refrigerator. If you must keep them for more than a short period of time, store them in the freezer to prevent mold. An average slice of white bread will yield about one-half cup of fresh bread crumbs; a slice of dry bread will yield one-quarter to one-third cup dry bread crumbs.”

Q: I’ve purchased unrefrigerated jumbo eggs from stores at the same price that some supermarkets sell small eggs. A friend says these less expensive eggs are as nutritious as the others because eggs may be kept up to six months. Just how long do eggs keep and how long is their nutritional value retained?

A: Publications from the American Egg Board state that freshness of eggs is determined by how recently an egg was laid, the temperature and humidity at which it is stored and how it is handled. “These variables are so important that an egg one week old, held under ideal conditions, can be fresher than an egg left at room temperature for one day.”

According to the board, “The ideal conditions (for egg storage) are temperatures that don’t go above 40 degrees and a relative humidity of 70% to 80%. Fresh shell eggs can be stored in their carton in the refrigerator for at least four to five weeks. Grade quality losses should be insignificant if the eggs are refrigerated as soon as possible after purchase from a refrigerated case.

“As an egg ages, the white becomes thinner and the yolk becomes flatter. These changes do not have any great effect on the nutritional quality of the egg or its functional cooking properties in recipes. Appearance may be affected, though. When poached or fried, the fresher the egg, the more it will hold its shape rather than spread out in the pan. On the other hand, if you hard cook eggs that are at least a week old, you’ll find them easier to peel after cooking and cooling than fresher eggs.”

Address questions on food preparation to You Asked About ..., Food Section, The Times, Times Mirror Square, Los Angeles 90053. Personal replies cannot be given.