Unveiling the Complexity of Pu-Erh Tea Flavor: Integrating Chemistry, Processing, and Sensory Neuroscience

Pu-erh tea, a geographically indicated tea product from Yunnan, China, is renowned for its unique flavor profile shaped by intricate chemical compositions and complex processing techniques. This review systematically summarizes the material basis of Pu-erh tea flavor, focusing on key taste, sensation and aroma compounds such as tea polyphenols, alkaloids, amino acids, and volatiles. A major highlight of this review is its integration of molecular sensory science, detailing taste, sensation, and odor perception mechanisms mediated by key receptors. The interplay between flavor compounds is explored to decode the complexity of Pu-erh tea's flavor profile. The transformation pathways of these components during critical processing steps are elucidated, highlighting microbial succession and enzymatic reactions that drive the evolution of sensory attributes like bitterness, sweetness, and aged aroma. Advanced analytical methods, including quantitative descriptive analysis, electronic nose/tongue, and computational approaches like molecular docking, are discussed for their roles in bridging chemical data with flavor perception. Despite advancements, challenges remain, such as clarifying the molecular basis of sweet aftertaste and optimizing numerically controlled fermentation. This review provides a multidisciplinary framework for future research, emphasizing the convergence of metabolomics, sensory neuroscience, and artificial intelligence to advance Pu-erh tea flavor science.