Thermosonication enhances the antioxidant quality of tomato juice: Enzyme inactivation kinetics, targeted metabolomics of carotenoids and phenolic acids, and multivariate correlation analysis.

Abstract

Thermosonication (TS) enhances tomato juice antioxidant quality, yet its effects on enzyme activity and bioactive compounds remain unclear. This study compared TS (60 °C, 15 min) and traditional pasteurization (TP; 85 °C, 10 min) regarding color, enzyme inactivation kinetics, and bioactive profiles. Both first-order and Weibull models described enzyme inactivation, with Weibull giving higher R2, especially for POD under TP (0.982 vs. 0.891). Targeted metabolomics revealed significant increases in carotenoids (lycopene, +12.8%) and phenolic compounds (chlorogenic acid, +93.7%; rutin, +108.3%; syringic acid, +596.6%). TS better preserved ascorbic acid and color (ΔE = 1.79), with higher DPPH/ABTS activity in lipophilic and hydrophilic fractions. Correlation analysis suggested associations between enzyme activity and color, POD activity and phenolic oxidation, and phenolic acids/lycopene and antioxidant capacity. TS may improve antioxidant quality via oxidative enzyme inactivation, release of bound phenolics, improved extractability, and glycoside hydrolysis, offering a hypothesis-generating framework for high-bioactivity tomato juice production.