Preparation, characterisation, and application of gelatin/sodium carboxymethyl cellulose/peach gum ternary composite microcapsules for encapsulating sweet orange essential oil

Abstract

This study successfully developed a gelatin-sodium carboxymethyl cellulose-peach gum composite microcapsule system using the complex coacervation method. Optimal preparation conditions were determined by turbidity, complex condensate yield and encapsulation efficiency: the ratio of gelatin to sodium carboxymethyl cellulose was 7:1, the ratio of gelatin/sodium carboxymethyl cellulose to peach gum was 4:1, and the pH value was 4.2. The morphology of the system was evaluated using scanning electron microscopy and laser confocal microscopy. Structural properties and viscoelasticity were analyzed through Fourier-transform infrared spectroscopy, Raman spectroscopy, and rheology. Results indicated that adding peach gum enhanced the system's structural stability and solid behavior. Thermogravimetric analysis, differential scanning calorimetry, swelling, release, antioxidant, and antibacterial experiments confirmed that the addition of peach gum increased the thermal decomposition temperature of the microcapsule system to 246 °C, enhanced the sustained release capacity, and improved both the antioxidant effects and antibacterial properties. The highest lipid antioxidant value was 1.1 mg MDA/kg, while the total bacterial count reached a maximum of 5.3 log CFU/g, both of which remained below the threshold of food spoilage, thereby confirming the role of the gelatin-carboxymethyl cellulose sodium-peach gum composite system in meat preservation. The gelatin-sodium carboxymethyl cellulose-peach gum composite system's excellent sustained-release capacity, antioxidant effect, and the antibacterial properties of the gelatin-sodium carboxymethyl cellulose-peach gum composite system could provide a new carrier for the application of active substances in the food sector.