It took the artist Anya Gallaccio three days to paint the walls of an old farm building with chocolate. She used 40 kilos of 70 per cent cocoa solid, confectioner-quality dark chocolate. The same stuff they use to make handmade truffles.
To paint a room with melted chocolate sounds like heaven, a chocolate-lover's dream. Elbow-deep in it, licking it off your face and the walls.
"It's quite hard to keep on the brush, and soon it's up your arms and all over your face. At first, everyone starts eating it and they think it's really cool to lick their fingers. But the smell becomes intense. Gradually you try harder and harder to be more careful and avoid your mouth because it becomes repulsive. I don't eat chocolate for a while afterwards," says Gallaccio.
Gallaccio was shortlisted for the Turner prize in 2003 (Grayson Perry won) with a sculpture of real apples rotting on bronze trees. Much of her work uses organic materials, which disintegrate with time: ice, flowers and apples. Few of her works remain permanent.
At Jupiter Artland, Edinburgh, her chocolate artwork, Stroke, is a fairy-tale idea, like Hansel and Gretel or Charlie and the Chocolate Factory. But it turns out to be a brown room with a dark bench in the centre. Were it not for the smell, you'd never know you could eat the walls.
"The idea of a chocolate room sounds delicious but is almost disappointing. It feels like a small dark space. It doesn't look chocolaty, or edible. If you start looking it's painterly, you can see the marks. I kept it neutral because some people love chocolate and some people hate it. It's quite a blank open situation for the visitor to occupy in any way they wish. As with any artwork the ultimate experience is subjective," she says.
There's confusion between our nose and eye. We anticipate a feast for our eye but it turns out to be for our nose. Gallaccio points out smell triggers memories in oblique ways. Our minds might end up in strange places from a whiff of chocolate. It can set off strong feelings of desire or disgust.
"More traditional academic materials used in sculpture can be removed from everyday life but everyone has some kind of relationship with chocolate. There's an accessibility within it as an idea," says Gallaccio.
Gallaccio first installed a chocolate room in Vienna 20 years ago. Inspired by a weekend visiting cafés where she drank and ate chocolate, she decided to install a chocolate room in the city of chocolate. The opening night was warm, and the walls glistened. Visitors licked and nibbled at the chocolate, pressed their noses to it, scraped bits off with their fingers.
"I was shocked by how physical everyone got with it," she says.
In a London gallery the reaction was more furtive. Secret finger scrapes on a hidden wall, names graffitied. In Japan visitor pressed their noses and mouths into the walls, which surprised the artist as she expected restraint.
There's no temperature control in the room. What happens in the next two months depends on weather, visitors, and the alchemy of chocolate. Blooms of white mould might appear and as the chocolate rots the smell should intensify. When it's over they'll chuck it away.
"It's like cooking," says Gallaccio. "I like cooking and being a host. You can always do something better and different, and it's not just about the food but the company and the people. Making my work is to provide the food. The people and the context change it. It's a living thing."
‘Stroke’, Jupiter Artland, Edinburgh (01506 889900) to 14 July