THE EFFECT OF PACKAGING CONDITIONS AND STORAGE TIME ON THE VOLATILE COMPOSITION OF ASSAM BLACK TEA LEAF (VOL 49, PG 393, 1994)

Black tea leaf, vacuum packed in Assam and subsequently repacked in th e UK in standard air packs, under vacuum or nitrogen-flushed, was stor ed for up to 48 weeks. The volatile composition of the tea was assesse d at zero time, after 16 weeks and 48 weeks. Six compounds were identi fied as significantly different at 16 and 48 weeks when compared with the zero time sample (p < 0.001). These were identified as hexanal, tr ans-2-octenal, trans, cis-2, 4-heptadienal, trans, trans-2, 4-heptadie nal, beta-cyclocitral and beta-ionone, the level of these being at an increased level in the standard air pack and similar to the zero time sample in the vacuum- and nitrogen-flushed packs. These results are co nsistent with oxidative deterioration of the tea during storage. Subse quent canonical variate analysis was carried out using these six volat iles. Results indicated clear discrimination between the samples, in p articular between the standard air packs and the other samples. This o ffers the potential of using these compounds as indicators of tea arom a quality and as a means of distinguishing between tea samples based o n exposure time in air.