Exotic and organic teas are wooing tea drinkers and challenging traditional black tea’s dominance as never before, tea industry experts say, as a tea factory in Dubai bids to become the world’s largest.

The shift in global tea-drinking trends is felt at the Jebel Ali Free Zone, despite it being more than 2,000 kilometres from the nearest tea bushes in the lush misty mountains of South Asia andEast Africa.

Unilever’s Jebel Ali tea-blending and packing plant is in the middle of a major tea-consuming market – the oil-rich Middle East – and records the changing habits of tea drinkers.

The plant, producing 1.1 million tea bags an hour every day all year round, begins expanding later this year aiming to double its output within four years to become the world’s biggest tea factory.

The health properties of green tea are also helping the financial health of the whole tea industry.

Nations that export orthodox black tea, such as Sri Lanka, have in recent years begun a major drive to produce more green tea as well as exotic varieties.

Black tea goes through a process of fermentation, or oxidation, which changes the colour of the leaves from green to black.

Green tea production stops the fermentation and retains the colour of the leaves. But both varieties come from the same bush.

Decades ago, tea drinkers would opt for either black or green, but now there is a huge choice, and even the humble tea bag is available in an exoticpyramid shape.

Mainstream black and green have been joined by, among others, organic, herbal and infusions, single-origin, ready-to-drink and fruit-flavoured varieties.