# Effects of Tremella fuciformis Powder with Varying Particle Sizes on the Gel Properties of Soy Yogurt

## TL;DR

This study shows how reducing the particle size of Tremella fuciformis powder improves the texture and stability of soy yogurt.

## Contribution

The novel finding is that smaller Tremella fuciformis particles enhance soy yogurt gel properties through filler effects and stronger protein interactions.

## Key findings

- Reducing TFP particle size increased soy yogurt's water holding capacity to 99.44%.
- Smaller TFP particles improved gel network density and viscosity in soy yogurt.
- Non-covalent interactions in soy yogurt were enhanced with reduced TFP particle size.

## Abstract

This study aimed to elucidate the mechanisms by which Tremella fuciformis powder (TFP) improves the gel properties of soy yogurt by investigating the effects of TFP particle size on physicochemical properties and rheological behavior, combined with microstructural characterization and intermolecular interaction analyses. The results demonstrated that reducing TFP particle size (from 432.33 µm to 50.10 µm) significantly enhanced its hydration properties and increased the water holding capacity of soy yogurt to 99.44% (p < 0.05). Rheological analysis showed that reduced TFP particle size increased the apparent viscosity, storage modulus, and loss modulus of soy yogurt, consistent with the formation of a denser gel network observed via particle size analysis and SEM. While larger particles disrupted ordered protein cross-linking, smaller TFP particles enhanced soy yogurt gel properties by filling voids, during which volumetric expansion through water absorption reinforced gel matrix continuity. Zeta potential and intermolecular interaction analyses suggested that reduced TFP particle size enhanced non-covalent interactions in soy yogurt. These results indicate that TFP improves the gel properties of soy yogurt primarily through filler effects and protein interactions, providing a valuable reference for formulating stable plant-based yogurt products.