Saturation in Tea: Beyond Strength and Bitterness

For many tea enthusiasts, the “saturation” of flavor in a cup of tea is one of the most important indicators of quality. But is a tea's strength the same as its saturation?

In general, tea strength — how thick or light a brew tastes — can be adjusted by changing the leaf-to-water ratio, infusion time, or water temperature. However, increasing the concentration does not necessarily increase the richness or complexity of flavor.

While our tongues can detect five basic tastes — sour, sweet, bitter, salty, and umami — the aromatic profile of tea is far more complex. Tea leaves are known to contain over 700 distinct aroma compounds. The variety and quantity of these compounds — shaped by terroir, cultivation practices, and craftsmanship — largely determine the saturation of flavor in the final brew.

One of the many factors that affect flavor development is climate — particularly the weather on the day of harvest. Tea picked and processed during rainy weather is often referred to by farmers as "rain leaves." These leaves hold more moisture, and the humid air makes it harder for the leaf to wither properly — a process known in Chinese as “zou shui”, or “draining water.”

When withering is incomplete, the leaf’s cellular membranes do not lose permeability effectively, making it difficult for flavor compounds to develop in a continuous and complete way. As a result, the brewed tea has noticeably lower flavor saturation. Worse yet, the fragmented development of aromatic molecules disrupts how we perceive aroma before and after swallowing — making it hard for the scent to fully connect through retronasal perception.

To the drinker, this results in a noticeable disconnect: the tea feels thin, disjointed, and lacking in flavor cohesion — a phenomenon often described by tea professionals as “water taste.”

At this stage, roasting becomes the most effective way to enhance body and round out the tea. During roasting, polyphenols in the tea undergo thermal decomposition, breaking down into gallic acid, quercetin, and myricetin — compounds known to intensify aftertaste and sweetness.

Tea that is carefully and skillfully roasted not only solves the problem of thin mouthfeel and "watery" taste, but also becomes smoother on the stomach and more satisfying on the palate — with a warm, full, and lingering flavor profile.