Oxidation & Roast
A Camera Can Now Grade How Fermented Your Tieguanyin Is
A 2026 study taught machine-learning models to read Tieguanyin's fermentation stage from ordinary photos and hyperspectral scans, graded against a two-of-three vote among tea masters, not a chemical threshold and not one expert's word alone.
Oolong's Stem Holds More Linalool and Geraniol Than Its Leaf
A 2025 tissue-level study of Tieguanyin found the stem holds more linalool, geraniol and other floral compounds than the leaf. A 2022 study found leaf processed with its stem attached finishes lower in linalool and higher in nerolidol than leaf processed alone.
A 2025 Study Finds Rainy-Day Picking Cuts Wuyi Rock Tea Aroma
A 2025 GC-MS study found rainy-day-picked Wuyi rock tea carries 40 to 74 percent less floral and fruity aroma compound than sunny-day leaf.
A charcoal roast is a sequence of fires, rested months apart
Charcoal roasting is a sequence of separate fires, not one step, and each fire does distinct, measurable chemistry to the leaf. The practice also varies more across oolong styles than most tea copy admits.