Synergistic Benefits of Essential Oil Nanoemulsions in Orange Juice: from Antimicrobial Effects to Sensory Improvement and Computational Bitter Taste Predictions

Abstract

This study investigates the dual role of essential oil components (EOCs) in enhancing microbial safety and shaping sensory perception, specifically against Escherichia coli O157 in orange juice. Four EOCs—carvacrol, citral, linalool, and limonene—were tested in nanoemulsified (n-EOC) and suspended (s-EOC) forms, individually and at low heat. Nanoemulsified EOCs showed up to a 13-fold increase in antimicrobial efficacy, achieving a 5-log reduction in bacteria more efficiently than s-EOCs or heat alone. This synergistic effect enabled lower processing temperatures while maintaining juice quality. Molecular docking studies revealed strong interactions between EOCs and the bitter receptor TAS2R46, suggesting potential effects on bitterness perception. Computational predictions indicated specific binding affinities of each EOC to TAS2R46, highlighting their potential influence on sensory acceptability. Sensory analysis using principal component analysis (PCA) and hierarchical cluster analysis (HCA) showed distinct groupings based on EOC composition, with significant differences observed between control (P1), limonene (P2), carvacrol (P3), linalool (P4), and citral (P5) samples. Samples treated with mild heat at 54 °C for 10 min showed similar clustering, with minor variations related to acidity, a key factor in acceptability. The study underscores the importance of balancing antimicrobial performance with sensory attributes to optimize consumer satisfaction, demonstrating the potential of nanoemulsified EOCs to enhance both microbial safety and sensory quality in food products. By fine-tuning combinations of EOCs with mild heat, this research offers valuable insights into preservation strategies that ensure both safety and consumer appeal.