Microencapsulation of Tuber aestivum aroma: Model equations, antioxidant properties, correlation between fourier transform infrared and gas chromatography-mass spectrometry data, and morphological approach

This study optimized the microencapsulation of truffle volatile components (Tuber aestivum (Wulfen) Spreng.) using response surface methodology (RSM) to enhance their stability and functional properties. Critical parameters such as temperature, wall material composition, and maltodextrin-to-gum arabic ratios were optimized to improve encapsulation efficiency, yield, and antioxidant capacity. GC-MS analysis identified 35 volatile compounds, with sulfur-containing compounds like 2,4-dithiapentane (15.44 %), dimethyl sulfoxide (6.51 %), and diallyl disulphide (3.555 %) being major contributors to truffle aroma, alongside non-sulfur compounds including 1-octen-3-ol (58.78 %) and 3-octanone (4.28 %). The microencapsulation process improved the antioxidant activity of truffle extracts, with microencapsulated extracts exhibiting higher values in both DPPH and ABTS assays. Mathematical equations with P-values less than 0.05 were derived for each dependent variable in both Microwave-Assisted Extraction (MAE) and Heat Reflux Extraction (HRE) methods. SEM analysis revealed that the MAE method produced capsules with a more homogeneous morphology and smaller average diameter (30.88 µm) compared to those obtained by the HRE method (35.39 µm), contributing to better encapsulation efficiency. FT-IR analysis revealed that no covalent bonding occurred between the aroma and the wall material, indicating only weak intermolecular interactions such as hydrogen bonding. This finding supports the preservation of the truffle aroma's chemical structure, as further evidenced by the calculated CHx, C-Sx, S-Ox, and V-OH index values. Sensory evaluation, conducted with a trained nine-member panel using a five-point hedonic scale, demonstrated that microencapsulation preserved the characteristic aroma and taste of truffles, suggesting its potential for retaining truffle properties in culinary applications.