Cooking Seafood

Important tips

General rules

Do not overcook

No other food overcooks as easily as seafood. Overcooking seafood will spoil its flavour and texture, and decrease the moisture content of the flesh.

Seafood keeps cooking

Seafood should be cooked until it is almost done. It will continue to cook even after it is removed from the heat source, so should be removed a few minutes before completion of the required cooking time.

Simplify flavourings

Keep flavourings simple. Seafood has a delicate structure and flavour. These should be enhanced, not overpowered.
Delicately flavoured seafoods such as snapper and dory should be used with subtly flavoured ingredients such as lemon, lime or light sauces. Stronger flavoured species such as mullet and tuna can be enhanced with more strongly flavoured ingredients such as onion, garlic or wine.

When is it cooked?

Finfish

Assessing when finfish is cooked is a skill acquired with practice.
Just before finfish is done, the thickest part still clings to the backbone and a thin layer of translucent, uncooked flesh is left in the centre.
When cooked, the flesh will:
• be uniformly opaque, the translucent layer having just disappeared;
• flake, when tested with a skewer or fork;
• spring back when touched.

Shellfish

When cooked, the flesh will:
• have just turned opaque;
• be just firm, springing back when touched.
When cooked, the shell of most crustaceans will turn a shade of pink, orange or red.

Which cooking method with which species?

Most cooking methods can be used with a variety of seafood species and flesh types. However, some species or flesh types are more suited to a particular cooking method than others.
As a very general guide, species that have high moisture and/or oil levels are better suited to dry-heat cooking methods and microwaving, while species that are low in moisture and/or oil are better suited to moist-heat cooking methods and frying. (Of course, there are exceptions to these rules. See the cooking and preservation methods summary table on the following pages for cooking methods suited to some commonly used seafoods.)
If these simple guidelines are applied, an appropriate balance between the oil and moisture levels of the seafood and the cooking method can be achieved. The end result will be a desired flesh texture, rather than flesh that is too moist or oily, or too dry. Check the Species chapter for the moisture and oil levels of your chosen species.
The cooking methods appearing in the Species chapter suggest some of the more commonly applied methods for each particular group of finfish and shellfish. However, it is usually possible to use other cooking methods for the same species. The methods suggested are simply proven techniques that will enhance the flavour of the seafood and use its natural qualities to the best advantage; they do not have to be strictly adhered to. So use the recommended method, or be more adventurous and experiment with different techniques.

Cooking & preservation methods - summary

*Due to the longer intended shelf life of preserved seafood, these methods should be used only by those with appropriate food safety knowledge.

Moist-heat cooking methods

Steaming

The most common moist-heat cooking methods are steaming and poaching.
Steaming cooks the seafood by the heat of steam at a temperature slightly greater than 100^oC. The subtle, characteristic flavours of the seafood are retained.

Equipment

• Steaming equipment can be a simple bamboo steaming basket, a custom-made fish kettle or a sophisticated steam oven. Seafood can also be steamed in a conventional oven by wrapping in foil or placing in a covered dish.
• The choice of equipment depends on the size and quantity of seafood to be prepared.
• Pressure steaming of seafood is not recommended, except for cephalopods (for example octopus) and abalone, because the high temperatures toughen the protein very quickly.

How to do it

Finfish and crustaceans
1. Over liquid in a wok or steamer
Place the prepared seafood in a single layer on a rack or in a perforated steamer over the boiling liquid. Cover tightly, but take care not to overcook as the seafood will cook quickly.
2. In conventional oven
Wrap prepared seafood tightly, for example in paperbark, banana leaves or foil, and cook over liquid in a pre-heated oven. Alternatively, place seafood on a rack in a baking dish with a small amount of liquid and cover tightly with a lid.
3. In steam oven
Place prepared seafood in a perforated pan and cook on steam setting.
Bivalve molluscs
Steaming bivalve molluscs such as mussels usually opens the shells and cooks the flesh at the same time. When a shell opens, the mussel is cooked. However, not all shells open when cooked.
Place molluscs in a single layer on a rack over water or in 1 cm of liquid. Cover tightly and steam, shaking occasionally to allow shells room to open.

TIPS:
• Seafood can be steamed over plain water, but a concentrated stock flavoured with vegetables, herbs or citrus, for example, will impart a subtle flavour.
• The seafood can be lightly seasoned with herbs, salt and pepper, sprinkled with lemon juice or white wine and dotted with butter or basted with oil. Low-salt soy sauce and coriander can also be used.
• Wrapping in lettuce, cabbage, spinach or even seaweed can:
- add flavour
- shape the seafood
- portion control the seafood
- help keep the flesh together
- help retain moisture.

Cooking times

These will vary considerably depending on the species, thickness, quantity and initial temperature of the seafood, and on the equipment. The times suggested below are a general guide only.

Poaching

Poaching involves placing seafood in just enough liquid to cover it, and gently cooking below boiling point until the flesh becomes tender. The temperature should be 75-85^oC. Poaching is usually done on a stove but an oven can be used.
NOTE:
Poaching differs from boiling and simmering. Poaching requires a lower temperature than boiling (100^oC) and simmering (95-98^oC) and is therefore more suitable for cooking seafood. Boiling and simmering may cause the proteins to tighten, which results in toughening of the flesh. Boiling is also too rapid for seafood and may cause the flesh to break or fall apart. Poaching, although slower, will generate a better result. Seafood is occasionally blanched (i.e. briefly plunged into boiling water and then refreshed under cold water). However, blanching is used only to remove the skin, reduce strong flavours or extend the shelf life of seafood by blanching immediately before freezing-it is not a cooking method.

Equipment

• Almost any cooking pan that can hold the seafood in a single layer is suitable. A lid is optional, but it does help retain heat and prevent the poaching liquid from evaporating.
• For gilled and gutted finfish, fish kettles are ideal. If the kettle is large, it can be placed over two hotplates.
• A steamer designed to fit into a saucepan or wok can be used, as long as the poaching liquid can cover the seafood.

How to do it

1. The seafood can be wrapped, placed on a rack, or immersed directly in the poaching liquid. Wrapping before placing in the liquid will help hold the flesh together, while a rack or perforated pan will make it easier to remove the seafood, especially gilled and gutted finfish, from the poaching liquid.
2. Use only enough poaching liquid to cover the seafood. The liquid can be plain or salted water, a court bouillon, a fish fumet, wine, cider or even milk. Milk is especially suitable for strongly flavoured, smoked or salted seafood, as it helps counteract a salty or strong flavour.
3. Heat the poaching liquid to a simmer, then gently immerse the seafood. Bring the liquid back to poaching temperature (75-85^oC), and maintain heat at this level.
Optional: cover with lid or foil
It is also possible to poach seafood by immersing it in cold water, then bringing the water to 75-85^oC. This is not the optimal method, but if used, is better for gilled and gutted, large finfish rather than fillets. The cooking time should be calculated from when the water reaches the correct temperature.

TIPS:
• Ensure that the seafood is completely covered with liquid.
• Save the poaching liquid for use in accompanying sauces or for soups or stocks.
• If the seafood is to be served cold, it should be covered to retain moisture and flavour and then placed in a chiller for an hour or even overnight.

Cooking times

These will vary considerably depending on the species, thickness, quantity and initial temperature of the seafood, and on the equipment. The times suggested below are a general guide only.

These times are calculated from the moment the seafood is placed in the pre-heated poaching liquid.

Frying methods

The main frying methods are:
• deep frying (p. 269) and
• shallow frying (pan-frying, p. 271, and stir-frying, p. 273).

The temperature is important when frying seafood:
• if too high, the seafood will overcook on the outside, leaving the inside undercooked. The flesh may darken and be tainted with a bitter flavour.
• if too low, the seafood will absorb more oil and be greasy and pale in colour.

Vegetable oils are recommended when frying seafood:
Vegetable oils are made from a variety of vegetable products such as nuts, seeds and grains, each with its own distinctive colour, flavour and cooking property. Oils may be from a single plant source or be a blend of numerous varieties. A blended oil labelled "salad" or "vegetable" oil typically contains mixtures of soy, safflower, sunflower, corn or peanut oil. These oils are usually polyunsaturated (i.e. they are made up of polyunsaturated fatty acids).

From a health perspective, an oil with a greater proportion of mono-unsaturated or polyunsaturated fatty acids is recommended for deep frying seafood.

A blend labelled "for frying", while less expensive and having a high smoke point, is likely to be based on cottonseed, palm or coconut oil and could be high in saturated fatty acids.

Olive oil
This is a healthy and pure-tasting oil, but best for pan-frying or used as a condiment because it cannot tolerate the extended high temperatures needed for deep frying.

Canola oil
Canola oil is one of the healthiest cooking oils, as it is lower in saturated fatty acids and contains a higher proportion of monounsaturated fatty acids than many other oils. It has a high smoke point, making it excellent for deep and shallow frying.

Hydrogenised vegetable oils, palm and coconut oils
These oils have a high level of saturated fatty acids and therefore should be avoided.

Butter
Butter imparts an excellent flavour and browns food better than most oils. However, it has a low smoke point. To raise the smoke point other oils can be mixed with it, or the butter can be clarified to separate out the milk solids (which burn more readily) to produce ghee.
Butter also contains a high level of saturated fatty acids and so for health reasons should be used sparingly.

Deep frying

Deep frying involves cooking food by fully immersing it in hot oil or fat at 170-180^oC.

Equipment

• a thermostatically controlled deep fryer. The size of the fryer must match the quantities being cooked, and the heating element must allow for quick temperature recovery. Continuous filtering is also recommended to remove any crumbs or small food particles before they burn and spoil the oil.
• alternatively, a deep, heavy-based saucepan, half-filled with oil

How to do it

Coatings
Generally, the delicate flesh of seafood should be protected from the hot oil or fat by a coating such as breadcrumbs or a batter.
The coating seals in the moisture, allowing the flesh to cook gently in its own steam.
The coating also prevents oil from penetrating the food and stops the food from flavouring the oil.

Crumbs
1. Season the raw seafood, or if desired, season the dusting flour.
2. Lightly dust the seafood with flour to remove excess moisture and to help the coating to stick.
3. Dip the seafood into an egg wash (a mixture of beaten egg and a little milk-water or oil).
4. Finally, roll the seafood into the desired crumb mixture, which could be breadcrumbs, biscuit crumbs, cornflake crumbs or even crushed nuts.
Place the crumbed seafood, loosely covered, in the chiller for one to two hours. This allows the crumbs to "set" and the outside layer to dry out, resulting in a crisper coating.

Batter
1. First dust the raw seafood (frozen or chilled) with flour.
2. Completely submerge the pre-dusted seafood in the batter. Batter is a semi-liquid mixture of flour and liquid (such as water, milk, soda water or beer) and sometimes egg and other flavouring ingredients.
3. Remove from batter and gently shake off excess.
A chilled batter may produce a crisper coating. A light tempura batter and beer batter are particularly suited to seafood.

Cooking
1. Cut the seafood into even-sized pieces to ensure uniform cooking.
2. Apply the coating.
3. Heat the cooking oil to 170-180^oC.
4. Gently lower the prepared seafood into the oil with tongs or in a basket, or with gloved fingers if the seafood is battered.
5. Cook only a few pieces at a time. Overloading the oil will result in a drop in oil temperature and produce greasy seafood.
6. When cooked, gently shake off the excess oil, then drain on absorbent paper.
Do not fry from a frozen state unless using processed, packaged seafood specifically designed for that procedure; follow the instructions on the pack.
To increase its life, the oil needs to be completely filtered at least once daily, depending on the frequency of its use.

TIPS:
• Do not fry seafood with other foods, because the flavours will mix. Separate deep fryers are often used for different types of seafood, for example one for prawns and another for finfish.
• Cephalopods should be fried for a minimum time to ensure tenderness.
• Do not salt seafood before frying as the salt can cause the oil to break down.
• Lemon juice, vinegar or tartare sauce are the traditional accompaniments for deep-fried seafood as they help cut the richness of the oil.

Cooking times

These will vary considerably depending on the species, thickness, quantity and initial temperature of the seafood, and on the equipment. The times suggested below are a general guide only.

When the seafood is cooked the crumbs or batter should be golden brown, but this cannot be used as the sole indicator.

Shallow frying

Shallow frying is cooking in a small amount of oil, butter or similar medium. It includes pan-frying and stir-frying (wok cooking).

Pan-frying

Equipment

• any large, flat, heavy-based pan is suitable for pan-frying.
• alternatively, a flat grill plate can be used.

How to do it

1. Add the chosen cooking medium to a pre-heated pan or plate; clarified butter, a mixture of butter and oil, or olive oil are all good mediums.
2. Flour or crumb the seafood. To flour, lightly dust the seafood in plain
seasoned flour. The seafood can be dipped in milk before being dusted; this helps the flour to stick, especially if the seafood is dry. To crumb the seafood, follow the instructions that appear in the section on deep frying (p. 269).
It is not always necessary to flour or crumb seafood. Thick fillets can be pan-fried plain, or with a pepper or herb crust. However, the coating helps to hold the flesh together and prevents sticking. It also forms an attractive brown crust, enhances the flavour, and helps to prevent moisture loss.
3. Once the cooking medium is heated, add the seafood. Place finfish presentation (flesh) side down. This sears the presentation side and prevents the skin from curling at the edges, which is particularly important for thin fillets.
4. Cook over medium-to-high heat until just cooked. The heat should be reduced for thicker pieces of seafood.
5. Turn the seafood once only. Very thin fillets can be cooked on only one side.
6. Drain excess oil on absorbent paper and serve immediately.

TIPS:
• If flour is the only coating used, apply it immediately prior to cooking.
• Prevent sticking by ensuring that the oil is hot before adding the seafood. But make sure the oil is not so hot that it smokes (unless preparing a Cajun-style "blackened" fish).

Cooking times

These will vary considerably depending on the species, thickness, quantity and initial temperature of the seafood, and on the equipment. The times suggested below are a general guide only.

Stir-frying (wok cooking)

Stir-frying is a type of shallow frying where small pieces of food are cooked over a moderately high heat while being stirred continuously. In the case of seafood it is best suited to thick, firm-fleshed varieties.

Equipment

• a wok is most suitable.
• alternatively, use a large-based, high-sided non-stick pan.

How to do it

1. Cut the seafood and other ingredients into small or thin, even-sized pieces for quick and even cooking.
2. Heat a small amount of good-quality oil in the wok or pan.
3. Add the ingredients with the longest cooking time first. It is sometimes preferable to cook the seafood first, remove it from the pan, cook the other ingredients and then add the cooked seafood at the end. This prevents the seafood being overcooked while other ingredients are cooking.
4. Stir constantly by lightly tossing the ingredients.

TIPS:
• Use an oil with a high smoke point, such as canola or peanut oil.
• Frozen seafood should be completely thawed and drained before stir-frying. Otherwise this cooking method may cause a stewing effect.
• If desired for extra flavour, add liquids such as soy sauce, wine or rice vinegar when the seafood is almost cooked, cover and steam for 1-2 minutes.

Cooking times

As stir-frying is a very quick cooking method and as the pieces are small, care must be taken not to overcook the seafood.

Dry-heat cooking methods

Baking

The most common dry-heat cooking methods are baking and grilling.
Baking is a dry-heat cooking method that involves surrounding food with hot, dry air in an oven at a temperature between 140 and 250^oC. Oil is often added to the baking dish and brushed on the food to retain moisture.

NOTE:
Roasting is similar to baking. Roasted food is cooked in an oven between temperatures of 180 and 230^oC and basted frequently. Basting is not typically required for seafood, so baking is used more commonly.

Equipment

• an oven and a suitable baking dish; a kettle barbecue can also be used
• baking paper and a flat tray if cooking "en papillote"

How to do it

1. Optional:
• Season the seafood-avoid adding salt, as this tends to draw out the moisture.
• Score gilled and gutted finfish or thick fillets to ensure even cooking; make two or three diagonal cuts across the thickest parts on both sides.
• Stuff gilled and gutted finfish or rolled fillets.
2. Place seafood in a single layer in an oiled baking dish and brush the top of the seafood with oil. Fillets should be skin side up to protect the flesh and assist natural basting (see "Tips" below). Oily finfish can be brushed with lemon juice. Alternatively, gilled and gutted finfish or fillets can be wrapped in foil or placed in an oven bag. The foil should be lightly greased and the fish can be seasoned by adding herbs or lemon juice.
3. Cook in a pre-heated oven. The heat should be moderate (140-250^oC). Large finfish are best cooked at the lower temperature.

TIPS:
• Butter, margarine or olive oil can be used to add moisture and flavour.
• Skin on the finfish will provide a natural basting because most oil is stored

Cooking times

These will vary considerably depending on the species, thickness, quantity and initial temperature of the seafood, and on the equipment. The times suggested below are a general guide only.

Grilling (including barbecuing)

Grilling is a dry-heat method in which the heat comes from one direction. Usually it comes from above, but it can come from below. Heat from above may be from a salamander, for example, and heat from below from a grid, grill plate or char-grill.
Barbecuing is a form of grilling. For grilling on a flat plate, see also "Pan-frying".

Equipment

• salamander/grill
• flat grill or hot plate
For barbecuing you could need:
• charcoal barbecue
• electric barbecue
• gas barbecue
• char-grill

How to do it

1. Optional:
• Marinate with a chosen marinade.
• Season just before cooking, otherwise the seasoning could start to "cook" the flesh. Avoid using salt as it tends to draw out the moisture.
• Oil the seafood with a brush, as an alternative to greasing the grill or barbecue plate.
• Score thick fillets or gilled and gutted finfish with two or three diagonal cuts across the thickest parts, on both sides, to ensure even cooking.
• As it cooks, baste seafood with butter, oil or a marinade.
2. Grease and pre-heat the grill or barbecue equipment. An electric grill should have a medium-to-high heat, while a gas grill should have a medium heat. It is important that the grill be pre-heated to the required temperature before the seafood is placed in position. The heat must be strong enough to seal the flesh instantly, without burning it.
3. Place seafood 10-15 cm from source of heat if using a salamander or charcoal barbecue.
4. Cook finfish skin side (or where the skin used to be) first. This ensures natural basting.
5. Turn thick steaks and gilled and gutted finfish halfway through estimated cooking time. Thin fillets may not need to be turned. There is no need to turn the seafood if cooking under a salamander.

TIPS:
• Leave the head and tail on gilled and gutted finfish to retain moisture and flavour. This may also enhance the appearance.
• When making seafood skewers, push the pieces together so that the flavours will blend and the flesh will hold together.
• Skin on finfish fillets hold together better than skin off fillets.
• To prevent the skin from blistering and peeling off, wrap gilled and gutted fish in foil.
• For barbecuing delicate finfish, cover the grating with foil that has been perforated. You can also marinate in lemon or lime juice to firm the flesh.--

Cooking times

These will vary considerably depending on the species, thickness, quantity and initial temperature of the seafood, and on the equipment. The times suggested below are a general guide only.
As grilling and barbecuing can involve intense heat, extra care must be taken not to overcook the seafood. Cooking time is generally very short.

Microwaving

Microwaving is the use of microwaves (electromagnetic waves of extremely high frequency) to generate heat inside food.

How to do it

1. Score the flesh of gilled and gutted finfish or thick fillets, for more even cooking. If the seafood starts to split during cooking, lower the power or, if it is cooked, remove it from the oven.
2. Arrange seafood in a single, flat layer or roll it, to achieve uniform thickness. Space the seafood evenly around the cooking platter, placing the thicker edges pointing outward, and avoid having the seafood protrude over the edge of the platter.
3. Cover with cling wrap, paper or a suitable lid. A cover ensures moisture retention and even cooking, but leave a small gap to allow steam build-up to escape.
4. Re-arrange during cooking to ensure even cooking.
5. Use 70% power, and remove the seafood from the microwave oven when the outer edges are opaque, but the centre is still slightly translucent. Allow to stand for about two to three minutes, while tightly covered to keep in the heat.

TIPS:
• The seafood can be brushed with butter or margarine, or a small amount of other liquid, such as wine, seasoning, a mix of water and lemon juice, or court bouillon. This can be done before or during cooking.
• Remove
the eyes of gilled and gutted finfish or they may explode during cooking.

Cooking times

These will vary considerably depending on the species, thickness, quantity and initial temperature of the seafood, and on the equipment. The times suggested below are a general guide only.
For a 650 watt microwave oven:

Preservation methods - dry & wet salting

There are two basic methods of preserving food with salt: dry salting and wet salting (brining). Salt at appropriate concentrations inhibits the growth of bacteria and also aids the dehydration process. Salting is often done before other preservation or preparation methods such as smoking, although it can also be done simply to add flavour.
Dry salting is used to draw the moisture out of food, which helps to reduce the growth of unwanted bacteria.
Brining is a wet cure equivalent of dry salting. The brine, a flavoured solution of salt or sometimes sugar, both draws out moisture and permeates the seafood. The salt and sugar also inhibit bacterial growth.

Equipment

• a glass, enamel, glazed ceramic or stainless steel (never aluminium) container

The salting time varies. For example:
• skin slows the salt absorption
• exposed flesh absorbs salt more quickly
• firm-fleshed seafood takes longer to absorb salt than soft-fleshed seafood.
• oily finfish need about 25% longer than non-oily finfish
• if the seafood is placed in the chiller while salting, the time needed is significantly increased, even doubled.

Preservation methods - drying

Preservation methods - hot & cold smoking

Preservation methods - marinating

TIPS:
• The seafood must be of high quality.
• Pieces of seafood should be quite small, or sliced very thinly.
• Marinades are usually based on citrus juices.
• Take care, as lengthy marinating will reduce the seafood’s fresh flavour. If left too long, a salty marinade will tend to leach out the seafood juices and increase the salt content of the flesh. Lengthy marinating (longer than four hours) will firm the flesh.
• Seafood marinated for longer than four hours must be stored in the chiller during the marinating process.

Preservation methods - pickling

TIPS:
• Mussels should be steamed and opened before pickling, and abalone, cuttlefish, squid and octopus should be tenderised and par-boiled before pickling.