The edible-coating market for food products—particularly fresh fruits and vegetables—has grown from a small cottage industry in 1985, when only 10 companies were in the business, to more than 1,000 companies that exceed $100 million in annual sales today.
One of the gurus of the edible-coating industry, Attila Pavlath, PhD, currently with the USDA’s Western Regional Research Center in Albany, Calif., developed the calcium ascorbate coating that has brought packaged, ready-to-eat apple slices to fast food restaurants, grocery stores, and school cafeterias.
At the 246th National Meeting & Exposition of the American Chemical Society on September 10th, Dr. Pavlath said that the next big challenge he is working on is an edible coating that will stave off the unattractive white film that appears on baby carrots after several days due to drying of the outer layer from exposure to the atmosphere.
Just like the browning that appears on apples after exposure to the air, the white film on carrots doesn’t interfere with their nutritional value, Dr. Pavlath said. “But just try to tell your kids to eat it!”
Edible coatings, which are usually made of natural components including proteins, such as keratin and collagen, polysaccharides, such as starch and pectins, or fats and waxes, must be not only safe to eat, but also acceptable to the consumer, said Dr. Pavlath. “They should retain the original taste, texture, and appearance of the product. In addition, the taste buds should not be able to detect the coating’s presence. It is estimated that the thickness of the coating should not exceed .3-.4 millimeters, or the tongue will be able to detect it.”
To date, the coatings have been applied primarily to fruits and vegetables—with more success in some areas than others. The apple-slice market has grown from $1 million when Dr. Pavlath first developed the coating, to some $33 million today. But he said that attempts to develop edible coatings for avocados have been unsuccessful thus far.
“With appropriate research, I believe edible coatings could be used to help preserve meat products, cheese, dried fruits, snacks, and sandwiches as well,” Dr. Pavlath added.