Most of us think of snails as Gallic, yet, pre-Industrial Revolution, “wall fish” were a regular part of the British diet, popularised by the Romans. Over the years, they became another of the foods we once gathered from the wild that faded from our repertoire – until Heston Blumenthal’s snail porridge put them back on the menu.

Are there different varieties of snail? In Europe, there are two main eating varieties: the Helix aspersa (the common garden snail or petit-gris) and the Helix pomatia (the Burgundy or Roman snail). Those grown commercially in Britain tend to be the slightly larger, faster-growing Helix aspersa maxima (or gros-gris).

How are snails farmed? In indoor or outdoor systems or a combination of both, with breeding, nursery and fattening areas. Since snails are hermaphrodites, they can all lay eggs, which hatch into tiny snails, complete with shell. Andrew Downes of South West Snails, a small farm based in Devon that supplies leading restaurants around the country, houses his snails in polytunnels. “It’s as if they are in the open – they get fresh air but more protection, which allows them to grow a bit faster. And on sunny days, we open the tunnels.” They are fed on a mixture of cereal and herbs, such as marjoram, thyme and parsley. According to Downes, a snail lover who quit his job in advertising to take over the farm with business partner Andrew Hogg two years ago, “The herbs give the full, earthy, peaty flavour you’d expect from wild snails.” After 3-5 months, they are the size of a 50p piece and are then refrigerated “so they retract and are in semi-hibernation before they’re put into the cooking pot”.

What about tinned snails? Tony Vaughan, of L’Escargot Anglais, is a former photographer who started snail farming in the Eighties and now supplies around 4,000 a week to Blumenthal and other top chefs, either live, blanched or fully cooked. “The problem is there’s a big shortage,” he explains. “France, for example, has to import 75 per cent and has a ban on commercial collection between April and June, so most of those that are tinned are the giant African land snail,” says Vaughan. “They’re so big that only the juveniles are used, but because their flesh is granular, they absorb all the brine, so, after six months, they’re tainted with it. Tinned European snails, which are fully grown and more tightly packed, are more resistant, but, even so, in eight months or so, even their meat will be really salty.”

Where to buy? South West Snails sends out live snails, snail meat and snails simmered in court-bouillon, then put into shells with garlic, shallot and parsley butter, or gorgonzola, chive and garlic butter, and frozen, £5.50 for 12 plus courier fee (07939 290265; www.south-west-snails.co.uk). L’Escargot Anglais snails can be bought from the farm at Credenhill, Herefordshire (01432 760218; no mail order), or frozen, in garlic butter, £22 per kg, from La Fromagerie, London (020-7935 0341; www.lafromagerie.co.uk).

Readers’ queries

Where can I buy fregola (Sardinian couscous-like pasta grains)?

Vallebona sells it for £2.85 for 500g (020-8944 5665; www.vallebona.co.uk).

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

Explore Food & Drink

• Gordon Ramsay

• Heston Blumenthal

• Recipes

• Wine

• Real Food

• Drinks

• Anjum Anand

• Eating Out

• Video Recipes

Times Recommends

• Gordon Brown’s favourite pud
• Five-spice butternut soup
• How to make popcorn and crisps