Tea aroma retention strategies using tea polysaccharide conjugates: Insights from the yellowing process

The quality degradation resulting from tea fragrance dissipation is a critical bottleneck hindering the advancement of the tea industry. This study explored how yellowing treatment influences tea polysaccharide (TPS) conjugates to enhance flavor in a natural and safe manner. The results demonstrated that yellowing treatment substantially increased the yield of TPS and formed structures enriched with phenolics and proteins. SPME-GC-MS analysis and in vitro simulation experiments revealed that yellowed TPS (YTPS) exhibited superior capacity for retaining tea aroma. Specifically, the proteins within the YTPS conjugate played a key role in stabilizing the aroma, whereas the phenolics competed with aroma compounds for binding to galacturonic acid carboxylic groups. These findings provide a novel strategy for enhancing the aroma stability of tea products by modulating the composition and structure of TPS.