Fish & seafood – tips on how to know how much to buy | The world of food and cooking

fish-and-shrimps-3952313We are huge fish and seafood lovers and we eat this very delicious food every time we have a chance. Most often we eat salmon, sea bass and sea bream but we also buy turbot and cod, as well as few other kinds of smaller local fish we can get locally (we currently live in the northern part of Bulgarian Black Sea coast). Mussels, shrimps and crabs are regularly on the menu, too. Of course, we prefer them fresh, but sometimes we buy frozen, too.

We slowly learnt how to tell if a fish is fresh by reading about the topic here and there and most importantly by talking to fishmongers and fishermen. Also, we would like to think that every day we are getting better and better at cleaning, filleting, skinning and storing fish.

But this post (that’s been on my list of posts for long, long time) will be strictly and only about the right portioning. It was one of the first things we were not sure about and we still have doubts from time to time, when buying, say octopus, crabs or whole fish: how much or how many will be enough for the two of us, or for when we invite 4 more friends for dinner.

Our idea of “the right portioning” is a general serving that is still healthy, and will not leave you with excess leftovers, but one certainly bigger than a portion you will be served in a fancy restaurant.


Fresh fish is sold in number of ways. The easiest choice for easier preparation and portioning is to buy in the form of fillet or steak. Fillets are two sides of fish, cut lengthwise from the backbone, that are usually boneless and ready to cook.

Round fish are the ones which have a backbone along its upper body and an eye located on each side of its head. This group includes species such as Mackerel, Sea bass, Sea bream, Haddock, Mullet, Pollock, Snapper, John Dory, Cod, Whiting, Trout, Cod, Pike and Salmon, as well as others. When portioned (meaning filleted), you’ll need to allow from 130 to 230g (1/3 to 2/3 pound or 5 to 8 oz) per serving.

For filleted Flat fish (the species that have both eyes on the same side of the head, such as Flounders, Soles, Turbot, Plaice and Halibut), you will need slightly less than the round fish – 130 to 180g (5 to 6,5 oz).

Or, in other words one kilo of filleted fish will produce 5 to 7 portions.

Fish Steaks are widthwise fish slices and usually are considered to be a portion. Choose slightly larger steaks (between 170 – 300g per person), as they have more parts (such as fat, skin or bones) of the total portion quantity to be discarded of.

whole-sea-bream-9080793Oily or white fish?

When portioning fish you need to know which one of these two types you’re dealing with. For oily fish (such as sardine, herring, anchovy, salmon, trout and mackerel) you need to keep the portions on the smaller side of the above mentioned numbers. In order to balance the beneficial qualities of the Omega 3 fatty acids against the potential dangers of ingesting methylmercury (MeHg) food standards agencies and health organizations recommend portions around 140g, 1/3 pound or 5 oz per serving. They also advise to eat a maximum of 4 portions a week for men, boys, and women past childbearing age, and up to two portions a week for women of childbearing age, including pregnant and breastfeeding women, and girls.

For the same reason, if you are pregnant or nursing your child, or thinking about becoming pregnant, it is important that you avoid consuming shark, swordfish, king mackerel or tilefish. It is also not recommended to offer these types of fish to children under the age of 6.

The good news is there is no recommended limit on the consumption of white fish (such as cod, whiting, haddock, hake and Pollock). They are generally lighter than oily fish, so you can keep the portions to the above mentioned weights.

Whole fish

That is how we prefer and most often buy our fish – exactly as they came from the water. This way you can check the freshness yourself – the eyes should be clear and the skin shiny with tightly clinging scales.

If you buy it whole and intend to fillet it yourself (before cooking), buy double the weight you need to serve – or 300 – 450g (one pound or 16 oz) per serving. If you’re going to cook it on the bone, you’ll get 5-15% more flesh off (it depends on the type of fish).

See our favorite fish recipes – Baked sea bream with sage and lemon sauce, Pan fried salmon fillets with sauteed fennel, Whole sea bream stuffed with sun-dried tomatoes, basil and thyme, Fish pie, Foil-baked salmon with zucchini, olives and herbs.


Lobsters and crabs

For this kind of shellfish you’ll need around 500g (1 pound) per person for a main course. This usually means a small species, or if you buy larger, you have to split them into two portions.

Prawns and shrimps

Prawns and shrimps are sold in number of ways. If you choose whole fresh ones, you’ll need around 300-400g (0,6 to 0,8 pounds or 10,5 – 14 oz) per person. As the frozen shrimps and prawns are usually precooked, with heads and shells removed, if you choose this option you’ll need half the quantity of fresh ones per portion – 150-200g (0,3 – 0,4 pounds or  5 – 7 oz).

See our favorite shrimps and prawns recipes –  Avocado, Mango and Prawns salad, Black rice and caramelized vegetables with prawns, Spicy Butter Shrimps.

Octopus and Squid

When buying octopus or squid for a main course you’ll need around 200 – 250 per person, if you’re going to prepare it on the grill and bit less (around 180 – 230g), if you’re going to stuff the squid tubes.

Clams, Mussels and Oysters

When serving mussels or clams as an appetizer, allow 250g per person (approximately 1/2 pound or 9 oz). If the mussels are to be served as a main course, allow 450g (1 pound or 16 oz). For this type of seafood always buy a bit more than the quantity needed, just in case you need to discard some, because they didn’t open during the cooking. See more about how to choose, clean, cook and store mussels or try one of our favorite mussel recipes – Lovage Mussel Soup and Stuffed Mussels.

If you’ll serve oysters you need to allow 4-6 oysters per person.

And lastly, if you’re going to serve smoked salmon, you’ll need to around 100g per person.

Here is the concise version of the above information in form of a table:

Type of fish or sea food Course Grams  per person Pounds per person Ounces per person
Fish – round, filleted Main 130-200g 0,3 – 0,4 lb 5-7 oz
Fish – flat, filleted Main 130-180g 0,3 – 0,4 lb 5-6,5 oz
Fish Steaks Main 170 – 300g 0,4 – 0,6 lb 7- 10,5 oz
Fish – oily fish, filleted Main 130-140g 0,3 lb 5 oz
Whole fish – prepared on the bone Main 300-450g 0,6 – 0,8 lb 10,5- 14 oz
Lobsters, Crabs Main 450 -500g 1 pound 16 oz
Prawns, Shrimps – fresh Main 300-400g 0,6 – 0,8 lb 10,5- 14 oz
Prawns, Shrimps – precooked Main 150-200g 0,3 – 0,4 lb 5 – 7 oz
Octopus, Squid Main grilled 200-250g 0,4 – 0,5 lb 7 – 9 oz
Octopus, Squid Main stuffed 180-230g 0,4 – 0,5 lb 7 – 9 oz
Clams, Mussels Main 450g 1 pound 16 oz
Clams, Mussels Starter 200-250g ½ pound 8 oz
Smoked salmon Main 100g 0,2 lb 3,5 oz



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