Fish farming has its critics, but when it comes to mussels there are few dissenting voices. Not only does sustainable farming get the thumbs-up from the Marine Conservation Society for preserving stocks and respecting the environment, but mussels grown on ropes suspended from rafts don’t touch the sea bed and rocks to which wild seed naturally attach themselves. As a result, the mussels don’t have the grittiness that puts many people off, according to fish merchant Andy Race, based in Mallaig in Scotland.

Race’s mussels are grown locally by shellfish farmer Iain McKinnon. “The waters are cold so the mussels grow slowly, developing their flavour,” says Race. “Also Iain spreads out the ropes, so there is plenty of room for clean water to circulate and enough food for the mussels to get lovely and fat.”

Does size matter? Mussels are mature after 1 year and are usually harvested at around 3 years, but can live for 10-15 years, and grow up to 10cm. Size depends on the amount of food available and the time of year, but flavour-wise size makes little difference.

Are farmed mussels seasonal? In April the mussels’ energy goes into reproducing rather than building bodyweight “so they tend to be a bit small and weak and less flavoursome”, says Race. “What we hope for is a fortnight of hot weather in April, to get them in the mood to spat quickly and then recover.”

Why are some mussels orange and some pale? It is thought that the orange ones are female, the pale ones male or immature females. “They taste pretty much the same,” says Race, “but people instinctively prefer the look of the orange ones.”

How should you cook them? Choose mussels with tightly closed, unbroken shells. Discard any that stay open when tapped. Pull off beards and scrub shells. For moules marinières, put in a pan with white wine, chopped onion and parsley over a high heat with the lid on, so they steam open quickly, tip into a colander with a bowl underneath and strain. Return the liquid to the heat and whisk in some butter, more parsley and black pepper. Discard any mussels that haven’t opened and pour the hot liquid over them.

Where to Buy: www.andyrace.co.uk; 01687 462626 (£3.20 per kg). Loch Fyne: www.lochfyne.com; 01499 600264 (£12 per 2.5kg).

Readers’ queries

Can you buy chocolate that doesn’t contain soya derivatives?

Most chocolate contains soya lecithin, a natural emulsifier obtained from soya bean oil. Virtually all the soya protein (to which some people are allergic) is removed, but there may be trace elements to which sensitive people might react. The French chocolatier Bonnat makes single-origin bars without lecithin. Mail order from www.chocolatetradingco.com and www.mortimerandbennett.co.uk or from www.bonnat-chocolatier.com.

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