Edible antibacterial gelatin/zein fiber films loaded with cinnamaldehyde for extending the shelf life of strawberries by electrospinning approach

Abstract

Strawberries are a kind of nutritious fruit but they are easily spoilt by mold. Therefore, it is significant to prolong the shelf life of strawberries for the avoidance of their numerous wastes. To achieve the aforementioned objective, in this paper, the edible and biodegradable natural polymers of gelatin/zein were used to prepare the antibacterial fiber films loaded with cinnamaldehyde by electrospinning method. The fibers prepared in this study were smooth and bead-free, with the average diameters ranging from 1.46 to 2.02 μm. The successful encapsulation of cinnamaldehyde in obtained fiber films was confirmed by Fourier transform infrared spectra. The prepared fiber films decomposing at about 230 °C were shown by thermogravimetric analysis curves, indicating their high thermal stability. The amorphous structure of the polymers in the produced fiber films was displayed by X-ray diffraction curves. Compared with the untreated strawberries, strawberries treated with fiber films encapsulated with 15 wt.% and 20 wt.% cinnamaldehyde showed the smallest changes in appearance, weight loss rate, hardness, pH, and total soluble solids at 6 d. The shelf life of strawberries was increased to 6 days by the fiber films containing 15 wt.% and 20 wt.% cinnamaldehyde. The fiber films prepared in this study were potentially expected to be used as edible antibacterial packaging films, nutrient and drug carriers.