Encapsulation of Ascorbyl Palmitate in Zein by Electrospinning Technique

Abstract

In this study, ascorbyl palmitate was encapsulated in electrospun zein fibers at different loading levels (2.5%w/v, 5%w/v and 10% w/v). HPLC, SEM, FTIR, XRD, DSC and BET characterized the resulting electrospun zein fibers containing ascorbyl palmitate. Results indicated that the diameters of electrospun zein fibers increased with increasing concentration of ascorbyl palmitate. The physical status of ascorbyl palmitate in electrospun zein fibers was determined by X-ray diffraction (XRD), and differential scanning calorimetry (DSC). Fourier transform infrared (FTIR) was used to study the interaction between ascorbyl palmitate, and zein. The results showed that there was hydrogen bonding between protein and ascorbyl palmitate. Pore size was characterized by N2 adsorption–desorption isotherms. Contact angle results showed that hydrophobicity of electrospun fiber mats was not affected by ascorbyl palmitate. Encapsulation efficiency of ascorbyl palmitate in electrospun zein fibers was about 22.5–65.5% w/v. Release study results indicated that pH and morphology affected the release. This is the first report describing that ascorbyl palmitate was successfully encapsulated in electrospun zein fibers. This product is intended to be used as an active coating for the delivery of ascorbyl palmitate to butter and other food products.