Controlling (bio)chemical conversions of health-related plant-based compounds by processing: The case of Brussels sprouts and leek

Brussels sprouts and leek are suppliers of multiple health-related compounds, yet understudied on how processing impacts their concentration. In this study, the plant tissue structure was altered by processing to direct endogenous enzyme-substrate interactions. For this, both conventional and novel processing techniques were employed. Heating intact vegetables prior to high shear mixing resulted in relatively good preservation of health-related compounds, attributed to a prompt inactivation of endogenous enzymes. Oppositely, high shear mixing prior to heating facilitated over 82% conversion for both vitamin C, S-alk(en)yl-L-cysteine sulfoxides (ACSOs) and glucosinolates. Pulsed electric field (PEF) treatment prior to heating, resulted in ±25% ACSOs conversion, yet no glucosinolates conversion. PEF treatment effectiveness is attributed to substrate-enzyme localization in the matrix and cell size. Vitamin K1 remained relatively stable during all treatments. It was postulated that higher concentrations of vitamin C protect carotenoids against oxidation pointing to interaction effects among health-related compounds.