2.8 Trillion Parameters Can't Compute the Taste of a Tea Leaf

In July 2026, Moonshot AI released Kimi K3 — a 2.8-trillion-parameter model, the world's largest open-source large language model. It reportedly designed a microchip autonomously in 48 hours, with no human intervention. The tech world erupted.

But as someone in the tea business, I thought of something else:

Can those 2.8 trillion parameters compute the taste of a tea leaf?

The answer is no.

Not because AI isn't capable. AI is powerful — it can process massive datasets, write code, and design chips. But tea making happens to be exactly the kind of task AI is worst at: it requires human judgment, human senses, and human experience. None of these can be scaled by stacking parameters.

Kill-Green: Watching Leaf Color and Smelling Aroma to Decide When to Stop

Kill-green (shaqing) is the first critical step in Puer tea processing. In traditional pan-firing, the wok temperature sits around 200°C (according to "Tea Manufacturing," a standard textbook). When fresh leaves hit the wok, the intense heat rapidly destroys enzyme activity, halting oxidation.

But when do you take them out?

Not by watching a timer — by watching and smelling. Watching the leaf color shift from bright green to dark green, watching the leaf edges curl slightly; smelling the grassy notes fade as a clean fragrance emerges. These changes are fleeting — a difference of seconds produces a different taste.

The tea maker's hands stir the leaves in a 200°C wok, relying on feel honed over a decade or more — when the friction of the leaves between the fingers changes, it means moisture has left; when the elasticity of the leaves changes, it means cell walls are softening. Sensors can measure temperature and humidity, but they can't make the integrated judgment: "it's time to take them out."

Rolling: Feeling Leaf Resistance to Judge How Well Leaves Are Shaped

Rolling (rounian) is the key step that gives tea leaves their shape. For Puer tea, machine rolling typically takes 20-30 minutes, while hand rolling can be completed in about 5 minutes (according to "Tea Manufacturing"). But time isn't the point — the point is the tactile feedback the tea maker receives during the process.

As leaves are rolled, the fingers must feel the change in resistance. Initially the leaves are stiff and resistant; as cells break and juices are released, the leaves gradually soften and form strips. When to roll gently, when to apply pressure, when to stop — all determined by touch. Too light and the leaves won't form properly; too heavy and you get excessive broken fragments. This delicate balance is difficult for machines to achieve.

Withering: Observing Leaf Condition and Smelling the Fading Grassy Notes

Withering is one of the most important processes in white tea and black tea production.

White tea withering typically lasts 48-72 hours, during which the tea maker continuously adjusts based on changes in leaf condition — leaves transition from stiff to soft, from bright green to dark green, grassy notes gradually fade, and floral-fruity aromas slowly emerge. There is no standard formula; the decision of when to stop withering depends entirely on the tea maker's experience.

For black tea, withering has more defined parameters: leaf moisture content should drop to 60%-64%, and withering temperature should not exceed 35°C (according to "Tea Manufacturing"). But even with these guidelines, the tea maker still needs to touch the leaves to assess softness and smell whether the grassy notes have sufficiently faded before proceeding to the next step.

Our Jinggu white tea is made from the Jinggu large-leaf varietal, hand-withered. With annual production of over a thousand kilograms, every batch requires the tea maker to assess withering readiness individually — the same batch of fresh leaves will need different withering times on sunny versus overcast days, not to mention differences in leaf tenderness and harvest timing.

Pile Fermentation: Sensing Temperature by Hand and Smelling Aroma Changes

Pile fermentation (wodui) is the core process for ripe Puer tea, and the step that most embodies "the human craft."

According to "Tea Manufacturing," the optimal pile temperature is 50-55°C (measured 50cm from the surface). Exceeding 65°C causes "core burning" — the leaves carbonize and the entire batch is ruined. The fermentation period is recorded as 25-30 days in "Tea Manufacturing," while "Puer Tea Science" notes approximately 45 days, with the difference stemming from variations in process details and target quality.

In practice, tea makers don't constantly watch a thermometer. When turning the pile, they plunge their hands into the tea to feel the temperature — warmly uncomfortable but tolerable is roughly 55°C; if it's unbearably hot, the temperature is too high and the pile needs immediate turning to dissipate heat. Simultaneously, they smell the aroma: from sour notes to rice-wine fragrance to aged aroma, each stage's scent signals the fermentation progress.

This "hands plus nose" approach may seem primitive, but in practice it's more sensitive and comprehensive than a thermometer. A thermometer measures a single point; hands can sense the temperature distribution across different parts of the pile. A thermometer can't smell, but the nose can capture subtle aroma shifts during fermentation.

Finished Product: Moisture 3%-5%, but Taste Isn't a Number

Finished tea should have a moisture content of 3%-5% (according to "Tea Manufacturing") — this is a clear, measurable standard. But the ultimate quality of tea — the layers of aroma, the body of the liquor, the persistence of the sweet aftertaste — these are what determine whether a tea is good, and they cannot be quantified by instruments.

AI can analyze the chemical composition profile of tea leaves and build models correlating flavor compounds with taste. But "did we kill-green this batch correctly?" and "how far along is this pile's fermentation?" — these judgments still need to be made by a tea maker standing at the wok or crouching beside the pile.

2.8 trillion parameters are impressive. But in the journey of a tea leaf from fresh leaf to finished product, there are too many things that parameters simply cannot compute.

The Value of Handcrafted Tea

Our Mangfei ancient tree tea comes from Mangfei Mountain in Yongde County, using ancient tree leaves. Ancient tree leaves are thicker and more irregular than plantation tea leaves, making them difficult for machines to handle. Handcrafted tea can flexibly adapt to the condition of each batch.

This isn't to say machine-made tea is bad — it's efficient, consistent, and perfectly adequate for everyday drinking. But if you're pursuing the upper limits of tea quality, the tea maker's understanding of and respect for every leaf, then the value of handcrafted tea is irreplaceable.

The AI era has arrived. But some things still require human hands.