Sweetness perception enhancement of thaumatin via gum arabic complexation: Improved thermostability and oral...

Thaumatin, a plant-derived sweet protein, is regarded as a promising sugar substitute due to its intense sweetness and favorable taste. However, owing to the complex environments and conditions involved in food processing, the limited thermostability of thaumatin (SP) significantly influences its application as a food additive. In this study, gum arabic (GA) was examined for its ability to improve the thermal stability of SP through the formation of stable complexes. Sensory evaluation results revealed that in the presence of 0.1% GA and 0.02% SP, complex exhibited improved sweetness characteristics after thermal processing compared to SP heat-treated without GA. Subsequently, the results of particle size, zeta potential, and spectral analysis indicated the formation of complex between GA and SP following thermal treatment, which was further supported by SEM and DSC analyses. At higher concentration of GA, the denser complex structures were formed after heat treatment, thereby improving the thermal stability of SP. Ultimately, the mucosal retention of SP was assessed using porcine tongue model. The results indicated that 0.5% GA significantly increased the mucosal retention of heat-treated SP, likely due to the formation of stable complexes between GA and SP. This dual improvement in thermostability and oral retention hold promise for broadening the applications of thaumatin in the food industry.