When a British Army surgeon discovered thaumatin in the rain forests of west Africa, he immediately recognised its importance as a sweetener. Quentin Cooper hears more about this unique substance when he talks to food scientists Mike Lindley and Steven Pearce . Also, Chris O'Toole , head of the Bee Systematics Unit at Oxford University, explains how, afterthe devastating effects of the varroa mite which almost halved bee populations in Europe, his team hasfounda way of enticing bees back to our gardens. Producer John Watkins
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