Controlled release and antibacterial properties of PEO/casein nanofibers loaded with Thymol/β-cyclodextrin inclusion complexes in beef preservation

There are still many limitations in the application of natural active compounds in meat preservation. Herein, thymol was first inserted into the cavity of β-cyclodextrin (β-CD) to form a stable inclusion complex (THY/β-CD-IC). The computational investigation showed that the optimized complexation energy for THY/β-CD-IC was -12.95 kcal mol-1. It contributed to the improvement of the thermal stability of thymol in the inclusion compound. Furthermore, the functionalized nanofibers (THY/β-CD-IC-NFs) loaded with THY/β-CD-IC were successfully fabricated by electrospinning of the mixture of casein and polyethylene oxide. When dealing with protease-producing bacteria, controllable release of thymol from THY/β-CD-IC-NFs was achieved through the response of casein to the hydrolysis of bacterial protease. The application results indicated that the prepared THY/β-CD-IC-NFs had a long-term antimicrobial activity for chilled beef preservation during 7-days storage. The information from this study presents a feasible strategy for the development of natural extracts for use in meat preservation.