Cooking with sustainable fish

Beyond cod

Keeping up to date on which types of fish a responsible consumer should avoid and which are in sustainable supply can be a slippery business.

So it's no surprise that, despite recommendations by food writers and conservation organisations, the top sellers in the UK are still the old standbys: cod, haddock, farmed salmon, prawns and tuna. Yet there's plenty more out there that's just as good to eat (and more sustainably fished) if you know what to look out for.

To take the pressure off overfished species, vary the species of fish you choose and seek advice from the Marine Conservation Society, whose website is a useful resource for green-minded fish-lovers.

Sourcing more-sustainable fish

Inland and coastal fish markets around the UK offer top-quality fish at fair prices. In some cases you'll only find locally landed fish, but markets such as London's Billingsgate (which is open to the general public) offer up to 160 species of fish at any one time. Most markets cater for a culturally diverse market, so there's plenty of scope for experimentation.

Traditional high-street fishmongers are something of a dying breed. It can be a struggle to find a good one, but if you do, treasure them and use them. There are also a number of entrepreneurial types who are beginning to see the business opportunities in fresh, sustainable fish, and there are some individuals out there who sell fantastic fish with passion and knowledge.

The traditional fish vans that roamed the streets in the 1970s are reappearing at many farmers' markets, often selling the freshest catch of the day from the nearest coastal market.

Frozen fish

Though it's often considered second-rate, frozen fish is worth considering, particularly if the fish is cleaned and frozen straightaway. Commercial freezers freeze fish quickly, so there's little damage done to the fish's flesh. If stored and then defrosted carefully, it can be difficult to tell the difference between properly frozen fish and fresh.

Some supermarkets have a poor reputation when it comes to availability and quality, but on the whole they do have a good track record for responsible sourcing. If you want to be certain, look out for the blue and white logo from the Marine Stewardship Council. To use the MSC logo, fisheries must first go through a certification process proving that their stocks are currently sustainable, so MSC-labelled fish can be enjoyed with confidence.

Whoever you buy from, look for quality and freshness. Key indicators are bright, clear eyes, a firm body, pink gills and a delicate fresh aroma.

Fish to look out for

Pollack

Pollack is related to cod and has similar white chunky flakes and flavour to match. Line-caught (particularly 'hand-line') pollack is a recommended buy because the fish are caught on individual hooks, from smaller boats.

Pollack is sold fresh, frozen and smoked, usually ready filleted, with the skin on. If you're cooking fillets leave the skin on; it helps to keep the flesh moist. Use tweezers to remove the pin bones from the thick part of the fillet if necessary.

Pollack can be roasted, baked, steamed or deep fried (it's gorgeous in a beer batter). It can be used in place of cod and haddock in many recipes. Simple butters, olive oil and other flavours all make the most of this succulent and meaty fish.

In 2009 Sainsbury's rebranded pollack because, according to their research, customers were too embarrassed to ask for it. They have renamed it colin, which is French for hake, a related fish.

Recipes

• Pan-fried pollack with curry spices, fennel, confit tomatoes and white onion purée
• Pollack goujons with tamarind sauce
• Indian-style pollack with spicy chickpeas

Wild Pacific salmon

The Atlantic Ocean is home to one species of salmon, the kind we're most familiar with in the UK, but there are several species of salmon native to the Pacific - all of which are important commercial fish in countries such as Canada, Alaska, Russia, Japan and New Zealand. They include the King salmon (also known as Chinook), Coho (silver salmon), Sockeye (red salmon) and pink salmon, Chum or Dog salmon and Japanese salmon. Sockeye and Coho salmon are the two Pacific species that are currently available in the UK.

Although Pacific salmon travels some distance to our shores, it's usually imported via boat rather than air, so has a lower carbon footprint than air-freight. It's sold in many fishmongers and retailers, sporting the familiar blue and white MSC logo.

Wild Alaska salmon has the most fantastic taste and is not 'overly fishy'. It's sold fresh, frozen and smoked, always filleted. Check for pin-bones and only remove the skin if absolutely necessary. Wild Alaska salmon is not like its Atlantic cousin. It's lean, firm and compact in texture and is prone to drying out if overcooked.

It can be grilled, pan-fried, steamed and baked. Adding citrus juice or wine to the dish as it's cooking can help to keep it moist. Otherwise, protect the fish with a buttery breadcrumb or couscous topping with lots of herbs and citrus zest.

Recipes

• Wild Alaskan salmon on herb mash with chilli garlic butter
• Seared wild Alaskan salmon and crab salad with fennel butter vinaigrette
• Poached wild Alaskan salmon with prawn and watercress sauce

Sardines

These oil-rich fish can be enjoyed with confidence. Sardines are actually young pilchards; they're fast-growing, making them pretty sustainable. It's the slow-growing, larger fish that are easily overexploited.

Very fresh sardines should still be in rigor mortis, which means they will be stiff and contorted in shape. The eyes will practically wink at you and the gills should be bright, fresh and pink. Sardines are easy to prepare: simply strip off the scales with the back of a knife, gut the belly and clean (some people leave the bellies intact, but the bloodline running up the middle can taint the flesh).

Simple flavours such as olive oil, basil, thyme and rosemary work well. They are excellent barbecued, grilled or roasted. Try pouring cold dressing of extra virgin olive oil, lemon zest, juice and freshly chopped oregano over hot fish straight from the oven.

Recipes

• Portuguese barbecued sardines with piri-piri oil
• Spicy sardines with chickpea and avocado salad
• Venetian-style sardines
• Escabeche of sardines
• Grilled sardines with sauce vierge, pan-fried Jersey Royals and salad

Red gurnard

Red gurnard is an underutilised species but, because there is no specific scientific data regarding its sustainability, enjoy it only occasionally. Gurnard has a bony head and sharp spines, so trim with care. The head and skin make excellent fish stock, but remove the gills and traces of blood first.

The tail is the part that is eaten and there is only a small proportion of flesh to whole fish, so choose larger specimens. Gurnard is best cooked on the bone because the small bones are difficult to locate.

Roast it whole with pancetta slices draped across the top to prevent the flesh from drying out or marinate it in olive oil and herbs and wrap in foil before barbecuing (they take just a few minutes). Gurnard is also an essential in Mediterranean fish stews such as bouillabaisse.

Recipes

• Fish soup with aïoli sauce
• Gurnard with shiitake mushrooms en papillote
• Arroz a la banda (saffron rice and squid with allioli)
• Moroccan fish tagine with coriander couscous
• Mediterranean fish soup

Rope-grown mussels

Most farmed shellfish require little intervention, so there's little damage to the environment. Rope-grown mussels are an excellent example. They grow like enormous bunches of grapes hanging in the water on thick ropes. Although available year round, they're best eaten during the autumn, winter and early spring months.

Mussels grown in this way have lovely shiny black shells that require little preparation. Just check that they're alive (open mussels that are alive will shut if sharply tapped) and discard any that don't close or that are damaged. Do not store in water, just in a bowl at the bottom of the refrigerator.

A traditional French way to serve them is as Moules marinière. Flavours such as ginger, garlic and lemongrass or saffron, fennel, dill and Pastis added to the steaming liquid make a good change.

A surprisingly good way to cook mussels is 'en papillote'. Drizzle garlic, butter and lemon juice over the mussels, wrap tightly in baking parchment and aluminium foil, then bake for about six minutes at 230C/450F/Gas 8 until the shells are completely open. Let your guests unwrap their own parcels - the aroma and taste is wonderful.

Recipes

• Mussels and jamon with sherry
• Mussels en croustade with leeks and white wine
• Mussels with dry coconut
• Mussels with wine and parsley (video recipe) by Mitch Tonks from Get Cooking

CJ Jackson is director of Billingsgate Seafood Training School in London.

Reviewed July 2009