Evaluation of the antimicrobial potential of tea tree oil Pickering emulsions stabilized by soy protein isolate-xanthan gum composite and their application performance in Solenocera crassicornis preservation

Abstract

The food industry has witnessed an urgent demand for natural preservation methods, particularly with respect to the aggravating microbial contamination situation in aquatic products. In this study, Tea tree oil (TTO) was encapsulated by employing a soy protein isolate (SPI) and xanthan gum (XG) composite as an emulsifying carrier, generating Pickering emulsions (PE) with high stability and potent antimicrobial activity. The emulsion demonstrated optimal stability at an XG concentration of 0.8 wt%, with an enhanced stability of the SPI-XG gel network. PE showed significant antimicrobial activity against bacterial biofilm and cell viability, surpassing that of the essential oil solution (EOS), indicating emulsification could boost antimicrobial efficacy of TTO. Treatment with PE disrupted cell membrane structure, causing leakage of nucleic acids and proteins, and inhibited biofilm formation. The preservation trial suggested that PE could extend the shelf life of red shrimp (Solenocera crassicornis) by 4 d, highlighting its potential in the food preservation industry.