I've heard that most apples have wax or shellac on them that's hard to wash off. I'm especially concerned about shellac -- is it safe to eat?
Yes, you can rest assured that even something called "shellac" can be safe for consumption.
While most people think of shellac as a time-honored wood finish, the natural substance comes from resin secreted by the female lac bug, found in Thailand and India. Many compare it to beeswax, another substance stemming from an insect secretion that's perfectly safe to eat.
Shellac, or lac resin, and waxes are often used on produce to help retain quality and reduce moisture loss. Like any food additive, the Food and Drug Administration demands that any such coatings used on fruits and vegetables meet FDA regulations for safety.
Many grocery stores and distributors require the coatings on produce they sell -- the coatings extend shelf-life and offer customers a higher-quality product. However, products with such coatings are labeled as such, so you can tell what you're eating -- signs and labels often say something like, "Coated with food-grade vegetable-, petroleum-, beeswax-, or shellac- based wax or resin, to maintain freshness."
The extra coating is needed because when produce is washed after being harvested and prior to being shipped for commercial sale, some of its natural waxy coating is lost. The coatings also help inhibit mold growth, protect produce from bruising, prevent other physical damage and disease, and enhance appearance, the FDA says. Only a very small amount is necessary -- just a drop or two per piece of produce. That amount is far outweighed by the natural wax still remaining on the fruit, but it has a big impact: Studies by the U.S. Department of Agriculture have shown that coated apples retain more moisture and firmness during storage than those that aren't coated.
Some people are bothered enough by the thought of these coatings that they are tempted to scrub their produce in soapy water. That's not recommended. First, anything more than rinsing produce under running water is unnecessary. Second, it's never a good idea to wash produce with detergent that's not meant for human consumption. It's illogical: You're trying to eliminate something that's edible by using something that's not.
However, you can avoid the coatings altogether by purchasing apples at farm markets. That way, you can ask the grower directly about any coatings (or lack thereof) on the produce they sell. Normally, only apples that are sold to retailers are coated.
For more information, see the FDA's web site at http://www.fda.gov and search for "produce safety."
Chow Line is a service of Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH, 43210-1044, or filipic.3@cfaes.osu.edu.
Editor: This column was reviewed by Diane Miller, tree fruit specialist with Ohio State University Extension and researcher with the Ohio Agricultural Research and Development Center.