Preparation of sodium alginate antibacterial porous composite pads embedded with centrifugally spun nanofibers by freeze-drying and recasting for active food packaging

Abstract

In this study, nanofibers composed of ethyl cellulose (EC)/polyethylene oxide (PEO) impregnated with tea polyphenol (TP) were fabricated by the centrifugal spinning method. Subsequently, these nanofibers were incorporated into sodium alginate (SA) to generate porous composite pads with varying fiber contents. The porous composite pads were comprehensively characterized. The findings indicate that the nanofiber structure of the porous composite pads is maintained, the porosity of the porous composite pads ranges from 16 % to 28 %, the water vapor transfer rate decreases as the fiber addition increases, and the thermal stability improves. Additionally, the pads demonstrated enhanced slow-release characteristics, and the cumulative TP release reached 70 % to 81.44 % within 120 h. All the porous composite pads could effectively inhibit the growth of Staphylococcus aureus and Escherichia coli, and the inhibition rates of the two bacteria were 99.69 % and 99.54 % respectively, highlighting their potential application in active food packaging.