Effect of fluoride on aroma of tea leaves

Seedlings of the Fu ding da bai variety of tea (Camellia sinensis, L.) were grown hydroponically for 30 days to study the effect on the aroma of the leaves at different concentrations of fluoride (F) ranging up to 10 mg F/L. Overall, the total relative aroma contents of the tea leaves decreased with increasing F concentrations. Volatile alkanes, alkenes, esters, acids, and anhydrides decreased with increasing exposure to F. Aromatic compounds, aldehydes, ketones, and phenolic compounds increased at first, but then decreased, whereas alcohols showed the opposite tendency. It is concluded that elevated concentrations of F during growth have negative effects on the aroma and flavor quality of tea leaves.