Electrospun potato starch nanofibers for thyme essential oil encapsulation: antioxidant activity and thermal resistance.

Thyme essential oil (TEO) is a great natural substitute for synthetic compounds in order to maintain the quality and safety of food products acting as an antioxidant agent. We aimed at the nanoencapsulation of TEO at concentrations of 1, 3, and 5% (v/w, dry basis) in electrospun nanofibers made of starch (50% w/v) and formic acid (75% v/v). Rheological parameters of the fiber-forming solutions were measured, and various physical and chemical properties of the nanofibers were analyzed.The starch/TEO nanofibers presented homogeneous morphology. The starch nanofibers showed high encapsulation efficiency (EE, 99.1 to 99.8%), that along with FT-IR spectrum and TGA analysis, indicate great protection of the phenolic compounds of TEO. The nanofibers with 5% TEO retained up to 50% of the phenolic compounds after exposure to thermal treatment. The antioxidant activity against DPPH radical of the starch/TEO nanofibers varied from 11.1 to 14.2% and the values of inhibition (29.8%, p ≤ 0.05) against hydroxyl radical were same for free TEO and the nanofibers.Owing to these properties, electrospun starch/TEO nanofibers can be applied in food products or food packaging. This article is protected by copyright. All rights reserved.