Edible Coating for Shelf-Life Enhancement and Deterioration Prevention of Fresh- Cut Apple

Abstract

Bay leaf (Laurus nobilis) has been used for many years as a food flavoring and in traditional medicine due to its antidiabetic, anti-diarrhea, antiviral, and anti-inflammatory properties. This work's objective was to assess the impact of bay leaf extract (BLE) at different concentrations (0, 4, 8, 12, and 15 mg/g) on the properties of edible coatings made of whey protein isolate (WPI) for shelf-life extension of apple slices. Fresh apple slice quality parameter such as weight loss, browning index, pH, and texture profile were evaluated. Antioxidant activity (Total phenolic content, total flavonoid content, and radical scavenging activity) and antimicrobial activity against different microbes (Salmonella Typhamirum, Escherichia coli, Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Candida albicans, and Aspergillus flavus) of BLE were investigated. Also, shelf life was studied by measuring antioxidant properties and also through microbial analysis for coated apple slices during 15 days of cold storage at 4°C. The results indicate that the quality properties of fresh-cut apple slices were improved by the addition of BLE. The BLE showed higher antioxidant properties such as total phenolic content (105.59 mg GAE/g) and free radical scavenger (67.13%). The addition of BLE especially in high concentrations of whey protein improved the antioxidant properties of fresh apple slices during storage periods. Adding BLE to coating solution could be a promising novel and effective natural antimicrobial agent (p< 0.05) when used concentration up to 12 mg/g.