Fears of frost in Brazil, mould on coffee beans in Italy and increased hedge fund activity have created a hot brew in the London coffee futures market, where prices struck another7-and-a-half-year high yesterday.

Robusta coffee, which is a stronger coffee bean than the more popular arabica variety, has in the past two months seen its strongest surge in 12 years, rising 78 per cent to about $2,040 a tonne. The robusta coffee market has been tightening all year as accelerating growth in consumption in emerging markets combined with lower-than-expected coffee exports from Vietnam and Brazil to produce a supply shortfall.