If ever an idiom did a disservice to a food, it is “mutton dressed as lamb”. The notion of someone beyond their youth trying to pass themselves off as a bright young thing has tended to sum up our image of this meat, which was once a British favourite, extolled by the likes of Mrs Beeton.

After the Second World War, changes in farming practices, the decline in the market for wool, and the fashion for young, tender lamb meant that animals began to be slaughtered at a younger age. And since mutton needs careful hanging (around two weeks) and butchering, and long, slow braising or roasting, it has been out of sync with the supermarket system and our fast food society. Now, however, the Mutton Renaissance campaign (www.muttonrenaissance.org.uk) is gathering force, with butchers and leading chefs such as Michel Roux and Nigel Haworth praising its flavour and texture.

When does meat from a sheep become mutton? The National Sheep Association defines mutton as meat from an animal over two years old, but it could be as mature as 4-5 years. (Below a year, it is lamb, and over one year, a hogget.) Some say the tastiest meat comes from a “wether” (castrated male); others prefer a ewe at the end of its reproductive life.

Does it have a season? The best time is October to March, when the animals will have been fattened on nutritious grasses.

Are some breeds better for mutton than others? Breeds traditionally associated with mutton, such as Welsh Mountain, Hebridean, Herdwick (Lake District), Southdown (Sussex), Romney and Shetland tend to be the most lean and tasty.

Should you buy organic? Bob Kennard of Graig Farm Organics, who has been championing Welsh Mountain mutton for years, points out that, beyond the issue of organic feed, “a non-organic sheep, because of its age, will have been exposed to chemicals for a long time. Organophosphorus dips (associated with health concerns and pollution) may have been used many times for disease, and animals may have been wormed routinely”.

Where to buy: Graig Farm Organics (01597 851655; www.graigfarm.co.uk), sells a whole leg for £9.40 per kg (it also supplies Harvey Nichols); Farmer Sharp (01229 588299; www.farmersharp.co.uk) is at Borough Market, £4.99 per 100g; Ardalanish Organic Farm (www.ardalanishfarm.co.uk), £10.95 per kg (buy through Loch Fyne, 01499 600264; www.loch-fyne.com).

Readers’ queries

Where can I find fruits for cheese? The most famous fruit paste for cheese is the Spanish membrillo (quince), which you will find in good delis. The Fine Cheese Co in Bath sells its own range of pastes (01225 448748; www.finecheese.co.uk).

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

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