Fortification of set yogurt with Tribute citrus essential oil: effects on physicochemical properties, multi-spectroscopic features, and microstructure

This study aimed to develop an alternative yogurt product with high consumer acceptance by evaluating the effects of <i>Tribute citrus</i> essential oil (TCEO) at various concentrations (0-10‰) on its physicochemical properties, multi-spectroscopic characteristics, microstructure, and sensory functionality. Increasing the essential oil (EO) concentration enhanced key parameters of set yogurt: The water-holding capacity increased from 0.64 (control) to 0.98 (10‰) (<i>p</i> < 0.05). Rheological behavior was altered, with the crystalline angle (2<i>θ</i>) decreasing to approximately 20°. The glass transition temperature also decreased from 76.45 °C to 74.32 °C (<i>p</i> < 0.05). A total of 88 volatile organic compound (VOC) fingerprints were identified using headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS), contributing 93.6% to the principal component analysis (PCA). Analysis through scanning electron microscopy (SEM) further highlighted a more uniform and dense microstructure. This research demonstrated the feasibility of fabricating high-quality EO-fortified set yogurt.