It’s a subject fraught with controversy, since few other commodities throw into such sharp relief the contrasts between the glamour and affluence associated with the finished product and the poverty endured by so many of the farmers who produce it. The exploitative nature of the coffee chain is highlighted in the movie Black Gold, which tells the story of an Ethiopian co-operative manager and his crusade to save it from bankruptcy.

According to the “Coffee Calculator” on the film’s website, only 1-5p of the £1.80 you spend each morning is likely to find its way to the farmers. The answer, though, is not to boycott coffee, as nearly 25 million farmers around the world depend on us drinking it. Instead, we have to ask questions about where we buy our coffee and support those who trade fairly. One such company is Union Hand-Roasted, started by Jeremy Torz and Steven Macatonia. “Our relationship goes beyond paying a fair price,” says Torz. “It is about participation, sharing the wisdom of exceptional growers in, say, Costa Rica, with small producers in Guatemala, helping them understand the value of what they grow.”

How many varieties of bean are there?

There are only two main species: the full-flavoured Arabica, which grows at high altitude and is the connoisseur’s choice (the higher the bean is grown, the better); and Robusta, which grows at lower altitudes, is more harshly flavoured and found in instant coffee and blends.

How do you account for differences in flavour?

Like wine, every terroir produces beans with a distinctive flavour, aroma, acidity level and body. “Costa Rican coffees,” says Torz, “tend to be crispy and zesty; with Guatemalan, the acidity balances red fruit and deep chocolate notes. East African coffees tend to be more citrussy; whereas Brazilian can be incredibly smooth, nutty and milk chocolatey.”

Do some beans have less caffeine than others?

An average green Arabica bean contains 1.2 per cent caffeine, whereas a Robusta bean can contain up to twice that amount. “To a certain extent,” says Torz, “if you drink coffee of a high quality, there is less caffeine in your cup.”

How is coffee decaffeinated?

Most of it is done using water and chemicals. The Swiss Water Decaffeinated Coffee Company has patented a process which uses only water and is 100 per cent chemical free. At Union Hand-Roasted, caffeine is removed using carbon dioxide, which they believe leaves the bean “the least disturbed”.

Where to buy:

Union Hand-Roasted (020-7474 8990, www.unionroasted.com).
Monmouth Coffee Company (020-7064 4950, www.monmouthcoffee.co.uk).

Readers’ Queries

Where can I find British “chorizo”?

At Piperfield Pork, Graham Head makes chorizo from the Middle White pigs he farms (01289 388543, www.piperfield.com ).

If you have a food query, e-mail food.detective@thetimes.co.uk

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