Effect of Rice Bran Waxing on Fruit and Vegetable Storage

Abstract

Sweet peppers and limes were coated with one of three wax emulsions—namely, rice bran wax (RW), carnauba wax (CW) or the two combined (CR). The emulsions were prepared and diluted to four concentrations. After waxing, samples were both physically and chemically examined. The optimum stability formula of RW required 121, 38.4, 24, 56 and 48 g of rice bran wax, oleic acid, triethanolamine, water and paraffin wax, respectively. The quantity of wax emulsion used was varied depending on the formulation and the fruit or vegetable. Sweet peppers and limes used a coated emulsion of 0.9–1.1% by weight. All the emulsions used were effective in retaining chlorophyll color and reducing weight loss. Limes with 10% CR had 22.8% weight loss after 30 d storage, which was similar to the unwaxed samples kept for only 10 d at 30–35 °C. Sweet peppers with 10% RW had only 9% weight loss compared with 18.3% for unwaxed sweet peppers after 7 d at 22 °C. Waxing reduced the changes in firmness, total acidity, pH and juice content.