Effect of K2CO3 micro-treatment of okara on quality and lipid digestion of fried tofu balls

Abstract

Excessive lipid digestion in fried foods leads to health risks like obesity, cardiovascular diseases. This study investigates the effects of micronized okara (MO) treated with weak alkali (K₂CO₃) on inhibiting lipid digestion in deep-fried tofu balls, and examines how varying MO proportions affect tofu ball quality and lipid digestion. The addition of 16 % MO significantly improved the texture of tofu balls, enhancing hardness, chewiness, and dietary fiber content. FTIR analysis indicated partial degradation of the dietary fiber fraction in the MO. SEM and XRD analyses revealed that 24 % MO resulted in notable structural changes, including void formation and reduced crystallinity. Simulated in vitro digestion showed that MO-containing samples had increased particle size and decreased free fatty acid release, with a 25.76 % reduction in total fatty acid release during intestinal digestion at 16 % MO addition. This study provides theoretical support for the preparation of fried foods with modifiable lipid digestion.