Alginate-based edible coating with magnoliae essential oil/β-cyclodextrin inclusion complex for Kyoho grape preservation

To prolong the shelf life of Kyoho grapes at room temperature, an edible coating composed of sodium alginate (SA) containing an inclusion complex of Magnoliae essential oil (MEO) and β-cyclodextrin (β-CD) (SA/MEO@β-CD coating) was developed. Initially, the inclusion complex of MEO with β-CD was developed to enhance its thermal stability. MEO@β-CD was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). In addition, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) results show that β-CD can improve the thermal stability of MEO. The entrapment efficiency and loading efficiency were 82.56% and 8.8%. MEO@β-CD was added to the SA coating for preserving Kyoho grapes, while monitoring the enzyme activity, total bacterial count, and sensory characteristics of the grapes. Compared to the uncoated group, the SA/MEO@β-CD coated group exhibited a significant reduction in total color difference, decay rate, weight loss rate, enzyme activity, and total number of bacterial colonies, while also slowing the decline in hardness and total soluble solids. The effect of the SA/MEO@β-CD1 group was highly effective. Conclusively, the SA/MEO@β-CD coating preserves Kyoho grapes by reducing lipid oxidation and inhibiting microbial growth, demonstrating its potential as an advanced edible packaging solution for grape preservation.