<b>Fruit</b>

Abstract

High gloss coatings are used to improve apple fruit (<b><i>Malus domestica</i> Borkh</b>) appearance and sales. The industry standard has been shellac-based formulations, which have problems with whitening, low gas permeability, and association with non-food uses. Zein, a natural corn protein, was used to formulate alternative, shiny coatings by dissolving zein in aqueous alcohol with propylene glycol (PG). At least 4% (by weight) PG has been found necessary for adequate gloss. However, increasing levels of both compounds resulted in increased gloss. Whitening, which occurred on the coated fruit surface upon wetting, was reduced by decreasing zein content to less than 11% [Bai <i>et al</i>, <i>Postharvest Biol Technol</i>, 2003, <b>28</b>(2), 259-268].