Microencapsulation with chitosan-embedded Houttuynia cordata oil: Integrating antibacterial and antioxidant...

Fresh pork is difficult to preserve given its high water content and nutrient density. The controlled release of encapsulated essential oils may be an effective way to prevent spoilage. The aim of this study was to develop chitosan (CS) and carboxymethyl tamarind gum (CTG) wall material for Houttuynia cordata oil microcapsules (HCOMs) for use in pork preservation. We adopted a complex coacervation method utilising CS and CTG to encapsulate H. cordata oil. Differential scanning calorimetry and thermogravimetric analysis revealed significantly enhanced stability of the oil. Moreover, HCOMs displayed sustained release and excellent antioxidant activity (DPPH scavenging activity 38.89 %, ABTS scavenging activity 40.03 %). The preliminary exploration of the inhibitory mechanism of oil and its microcapsules on Staphylococcus aureus showed that: 1 × MIC oil or microcapsules treatment extended the time for Staphylococcus aureus to enter the logarithmic phase to 14 h, while 2 × MIC completely inhibited the growth of bacteria, and suppressed the production of thiobarbituric acid reactive substances, maintained total volatile basic nitrogen content, and reduced the juice loss rate. Simultaneously, the pork's colour and texture were maintained, and its shelf life was prolonged. Hence, HCOMs exhibit excellent pork preservation properties with potential industrial applications.