Use of antimicrobial nanoemulsions as edible coatings: Impact on safety and quality attributes of fresh-cut Fuji apples

• Sodium alginate edible coatings formed from essential oil-loaded nanoemulsions.
• Edible coatings from nanoemulsions present a high antimicrobial activity.
• Nanoemulsions are more effective against bacteria than conventional emulsions.
• Fresh-cut apples shelf life extended up to two weeks by using edible coatings.

This work aims to study the effect of nanoemulsion-based edible coatings with lemongrass essential oil (LEO) at several concentrations (0.1, 0.5 or 1% v/v) on the safety and quality parameters of fresh-cut Fuji apples along storage time. Comparison between nanoemulsion-based coatings and coatings obtained from conventional emulsions is also provided. Edible coatings with LEO droplets in the nano range exhibited a faster and greater inactivation of Escherichia coli during storage time compared with conventional emulsions. Also, nanoemulsion-based edible coatings with LEO at 0.5% or 1% (v/v) completely inhibited the natural microflora of fresh-cut Fuji apples during 2 weeks and it was significantly slowed down with LEO at 0.1% (v/v). The droplet size of emulsions incorporated in edible coatings did not have a significant influence on the quality parameters during storage time. High LEO concentration led to reduced respiration rates and ethylene production. Significant browning was observed during storage time on fruits coated with high LEO concentrations (0.5 or 1% v/v), but not on those coated with 0.1% (v/v) of oil. Flesh firmness was maintained practically constant during storage time regardless the coating applied. These results contribute to evidence the potential benefits of incorporating nanoemulsions as delivery systems of antimicrobial compounds in edible coatings for minimally processed fruit.

Formation of nanoemulsions containing essential oils and sodium alginate and further formation of edible films onto fresh-cut Fuji apples.Figure optionsDownload as PowerPoint slide