The flowchart illustrates the sequential procedures involved in manufacturing black tea, contrasting the traditional method used for loose tea with the modern technique destined for tea bags.
Overall, the manufacturing process consists of several linear stages, beginning with manual harvesting and concluding with a drying phase that locks in flavour.
Initially, fresh tea leaves are hand-picked, a step where only the bud and two top leaves are selected to guarantee superior quality. Following this harvesting stage comes the withering phase, during which air is passed through the leaves on a rack to remove 60% of their moisture content. Once the leaves are sufficiently withered, the process splits. In the traditional method, the leaves are subjected to rolling, which flattens and breaks them, causing enzymes to be released from the leaves.
While the traditional method rolls the leaves slowly, the modern method utilizes a cutting, tearing, and curling technique. This modern mechanical process is significantly quicker than that of the traditional method, creating much smaller granular pieces. Despite these structural differences, both pathways converge at the oxidation and fermentation stage, where the processed leaves change to a copper colour upon exposure to air. In the final phase, the tea undergoes firing and drying in an oven, resulting in the elimination of 97% of total moisture and ensuring that the characteristic flavour and aroma are released for the consumer.