Effects of Kalimeris indica powder on Qingtuan (a glutinous rice starch gel food) quality and its potential mechanisms during hydrothermal processing

This study investigated the multifaceted effect of <i>Kalimeris indica</i> powder (KIP, 0 %-4 %) on Qingtuan, a traditional Chinese glutinous rice starch gel food, during hydrothermal processing. KIP enhanced color stability through chlorophyll encapsulation in a fiber-polyphenol-starch network, and 2 % KIP optimized chewiness (30.41 N·mm) and sensory acceptance (7.4 score), which were associated with modified microstructure, increased short-range ordered structures, and reduced crystallinity. Notably, KIP, rich polyphenols, and soluble/insoluble dietary fibers markedly reduced starch digestibility via physical barrier effects, enzyme inhibition, polyphenol-starch complexation, led to higher resistant starch content (24.8 %), and a lower glycemic index (78.6) at 4 % KIP. Although elevated KIP levels enhanced functional benefits, sensory trade-offs such as bitterness were observed, which necessitated careful optimization. This research demonstrated KIP's potential as a multifunctional, clean-label ingredient for enhancing Qingtuan's nutritional profile, providing insights into starch-bioactive interactions for the development of functional foods.