Degradation pattern of gibberellic acid during the whole process of tea production

The residues of gibberellic acid (GA3) in tea shoots, made tea, and tea infusion were determined by ultra-performance liquid chromatography tandem mass (UPLC-MS/MS) to study its degradation pattern during tea planting, processing, and brewing. The dissipation rate of GA3 was described using first-order kinetics. Its half-life ranged from 1.67 to 2.01 days in tea shoots. Degradation and concentration during green tea processing had equally important functions on GA3 residues in product intermediates and made tea. Except for water content, little GA3 residue difference was found in tea shoots and made tea. GA3 dissipated rapidly in the baking stage during processing. The transfer coefficient of GA3 residues from made tea to infusion was from 26.23% to 54.55%. GA3 extraction efficiency varied with different infusion times and concentrations of GA3 in made tea. This research revealed that GA3 may be safe when applied in tea gardens at suitable doses and picking intervals.