A Rainforest Alliance-

certified tea has joined Unilever's Lipton portfolio in a move to stamp its authority on the ethical tea market.

Lipton Kericho Estate Tea comes from Unilever's tea holdings in Kericho, Kenya. It has been blended for the UK market as a black tea best enjoyed with milk.

"This is a significant step forward in the tea industry," said category director Susan Gregory. "We have been working to ensure sustainability of our East African tea estates for over 15 years. Although there is a long way to go before all our tea is certified, this launch of Lipton is a momentous start."

The move follows the emergence of several niche tea producers aiming to steal share from the bigger players by flagging up their ethical credentials.

Meanwhile, Lipton Green Ice Tea has been launched in response to health trends.