EFFECT OF MAOFENG TEA PROCESSING ON LEAF TRICHOMES OF TEA (CAMELLIA-SINENSIS L)

Scanning electron microscopy was used to investigate the ultrastructure of trichomes on Maofeng, a special Chinese green tea. The trichomes were cylindrical in appearance with a length of 0.6-1 mm, wall thickness of 0.2-0.3 mum and a mid-point diameter of 9-10 mum. The angles between the trichomes and the leaf under-surface were below 30-degrees in Maofeng tea though they were 45-75-degrees in fresh green leaf. The trichome wall consisted mainly of fibre and its outer-surface was unevenly covered with waxy substances and striped. The trichome joint. by which the trichome was attached to the leaf lower epidermis, was expanded and filled with essential oil droplets. The undeveloped trichomes assumed a flattened form because of the action of pressing during rolling and shrank during the tea drying process. During the Maofeng tea processing, trichome shedding was caused by disruption of its expanded joint structure and breakdown at the cylindrical wall above the expanded joint.