Preparation of Coaxial Polylactic Acid-Propyl Gallate Electrospun Fibers and the Effect of Their Coating on Salmon Slices during Chilled Storage.

Abstract

Pseudomonas fluorescens bacteria can grow well in cold-storage conditions and cause food spoilage. Quorum sensing (QS) is a biological pathway existing in a large number of microorganisms, through which bacteria regulate several of their physiological activities. A number of substances have been identified as quorum sensing inhibitors (QSIs); they can interfere with the QS system and control bacterial spoilage characteristics and production of virulence factors. In our previous study, propyl gallate at sub-minimum inhibitory concentration levels showed a potent anti-QS activity. Thus, in this study, coaxial polylactic acid-propyl gallate electrospun fibers were fabricated and their physicochemical properties were characterized. Salmon slices were coated with these electrospun fibers and the effect of this coating on the salmon slices during chilled storage was evaluated. The results showed that the electrospun fibers had a small diameter and smooth surface with no beads or other defects. The thermal stability, tensile strength, and other properties of the fibers were suitable for refrigerated storage conditions. Without inhibiting the bacterial growth in the salmon slices, the QSI-containing electrospun fibers exerted a significant inhibitory effect on the production of total volatile base nitrogen and trimethylamine. Furthermore, the deterioration of muscle tissue in the salmon slices was significantly delayed during cold storage. Quantitative analysis indicated that the electrospun fibers had a significant inhibitory effect on the bacterial spoilage ability. The results suggested that the electrospun fibers loaded with QSIs might be an effective strategy to control food spoilage and enhance the quality of aquatic food products.