British tea and coffee lovers have had to swallow double-digit price rises on both beverages in recent years - but while the price of tea in the supermarkets has at last levelled off, coffee prices have continued to soar over the past 12 months.

Coffee is now 20% more expensive than two years ago, rising from an average of £18.58 per kilo in the top five supermarkets back in September 2010 to £23.26 per kilo today. In the past 12 months, coffee has become 12% more expensive - the equivalent of an extra £2.84 per kilo [BrandView.co.uk].

In-store coffee prices tend to lag what is happening on the commodity markets by about nine to 12 months, says BrandView account manager Matthew Ferguson.

“Looking at the decrease in raw material cost from the start of 2009 through to autumn of the same year, in-store pricing followed this trend from the start of 2010,” he explains. “The trend continued as raw materials rose from 2010 to the middle of the following year.”

Kraft’s Carte Noire coffee has risen by 30.9% to £31.76 per kilo in the past 12 months. Fairtrade brand Cafédirect went up 16.2% over the same period, to £20.98 per kilo, and Douwe Egberts rose by 15.9% to £29.24 per kilo.

Wholesale prices 22 September 2012: seafood

The prawn market continues to present a story of contrasting fortunes. Despite a 15.3% dip over the past month, coldwater prawns remain significantly more expensive than this time last year, driven up in part by declining stocks around Greenland.

Prices for warmwater prawns, on the other hand, have plummeted - at £5,565/tonne, they are now 32.6% cheaper than last year, having fallen by a further 0.8% in the past month. Warmwater prawn prices have fallen partly because the antioxidant ethoxyquin was recently detected in Indian prawns, which has greatly reduced their export potential, particularly to markets such as Japan.

UK favourites cod and haddock also remain on a downward trajectory - cod prices are now nearly 30% below their 2011 level, having fallen a further 8% in the past month, and haddock is down by 27.2% year-on-year and down 14% on last month.

Lavazza, however, has managed to keep a lid on increased raw material costs, with prices up just 0.1% to £14.86 per kilo.

Instant coffee has also become more expensive, with Kenco up 9.1% year-on-year (to £29.29) and Nescafé up 15.5% (to £27.03).

The past 12 months have been more kind to tea drinkers. In the past four years [48 m/e 19 September], the average price of tea in the mults has risen 12%, from £16.71 to £19.03 per kilo, but prices were up by a more modest 3% over the past year. In fact, several tea brands have actually reduced their retail prices - Typhoo is down 7.1% year-on-year to £7.93 per kilo and Unilever’s Lipton is now 11.3% cheaper than this time last year, at an average of £14.40 per kilo in the mults.

However, there could also be good news for coffee drinkers soon - the price of both Arabica and Robusta has fallen over the past 12 months, with Arabica down 36% year-on-year and Robusta down 6.4% [Mintec].

Once coffee lovers have sat out the typical nine-to-12-month lag between commodity movements and retail price adjustments, that cup of black gold could possibly be set to become more affordable again.