Characterization of aroma profiles in flat peach juice post-thermal sterilization: insights from comprehensive two-dimensional GC with time-of-flight mass spectrometry (GC×GC-TOF-MS), sensory analysis, and chemometric approaches

In this study, three thermal sterilization samples, namely pasteurization (PS), high-temperature short-time treatment (HTST) and thermal ultrasonic sterilization (TS) were employed to assess their impact on the flavor profile of flat peach juice through instrument detection and sensory analysis. Results showed significant differences in the sensory profiles among various thermal-sterilized samples, accompanied by diverse levels of reduction in volatile compounds. Totally, 175 volatile compounds were identified through the combination of GC-MS and GC×GC-TOF-MS analyses. Among these, 26 compounds were recognized as aroma-active compounds, displaying high relative odor activity values (rOAVs). Moreover, 5 sulfur-containing compounds were identified for the first time in the sterilized samples. Partial least-squares regression (PLSR) revealed a positive correlation between acetaldehyde, β-damascenone, (E)-2-octenal, and 1-octen-3-ol with off-odors and cooked attributes. This study offers crucial theoretical foundations for refining the processing technology of flat peach juice, thus facilitating the optimization of sensory attributes in juice products through the regulation of pertinent parameters.