I'm not a coffee drinker but even I couldn't help notice that back in February, coffee prices suddenly shot up, putting Starbucks in a bit of hot water.

Against this backdrop, I also noticed the launch of some coffee funds by specialist hedge outfit Eiger Trading Advisors. These four funds – two trackers (long and short), one managed alpha fund, plus a green/sharia-compliant fund – aren't likely to feature in many readers' portfolios as the minimum investment is $1m. But I think the launches are notable for a number of reasons.

First, coffee is a specialist commodity that lives up to its reputation as a non-correlated asset. In 2005, a couple of US academics released a paper called Facts and Fantasies about Commodity Futures 2005 (Gorton and Rouwenhorst) that spelled out why commodities as an asset class could be so useful. The key observation was the low correlation of commodities with equities.