Characterization of pectin with different structural features and its effects on Yogurt quality

This study investigated the effect of pectin’s degree of esterification (DE) and source on the quality of stirred yogurt. Commercial high-methoxy pectin (SP, DE 65.34%), watermelon rind-derived pectin (WP,DE 38.72%), and its enzymatically modified product (WPM) through pectin methylesterase (PME) treatment were characterized. PME treatment effectively reduced the degree of esterification (DE). All pectin improved the water-holding capacity (WHC) of yogurt at the concentration of 0.05 to 0.2 g/100 g, and WPM (lowest DE) exhibited the highest WHC (44.05%), while SP increased hardness but intensified sourness. SP increased the hardness and acidity of yogurt, while WP and WPM alleviated excessive acidification and helped maintain pH stability. Electronic tongue/nose analysis revealed that 0.2 g/100 g WP enhanced umami, whereas SP increased sourness. These findings demonstrate that both the DE and source of pectin critically influence in modulating yogurt texture and flavor. This study highlights the potential of watermelon rind pectin as a natural stabilizer for yogurt, offering superior texture and flavor modulation compared to commercial pectin. • PME treatment produced modified pectin with different esterification degrees. • WP and WPM improved yogurt water-holding capacity. • Pectin had minimal impact on yogurt color, while modified LMP provided a more balanced flavor.