Raw mackerel is delicious and sweet and tastes best straight from the sea. You can't get fresher
They rarely have worms etc if you avoid the inner organs, whereas I would generally avoid cod and herring which often are infested, but thats doesn't stop many people from eating them. One of my abiding memories of my first trip to Holland was slipping whole fresh new season, herring down my throat in one go
With seafood avoid any which may be from dodgy sources such as close to sewage outlets, with filter feeders such as oysters and mussels being the most likely to contain nasties in this type of environment. And always seek out fresh fish. I can't believe the sad, tired old stuff they sell on supermarket 'fresh fish' stores, most being thawed from frozen.
One of the great treats of mackerel fishing is some very fresh raw mackerel sashimi, with just a squeeze of lime juice, soy sauce and/ or wasabi paste. I can imagine chilled vodka being the perfect partner
bettered only by a chilled schnapps or especially a good aquavit
Try this recipe if you have access to super fresh mackerel;
Raw mackerel with horseradish and lemon
If you leave it to marinate for half an hour the lemon juice will cook the fish and transform the texture in the manner of a ceviche. I prefer it truly raw.
Ingredients
500g fresh mackerel fillets
1 tablespoon freshly
grated horseradish
2 lemons
1 teaspoon sea salt
1 teaspoon milled white
pepper
2 tablespoons olive oil
Method
* Make sure the pin bones have been removed from the fish and rinse it well under cold water. Lay the fillets on a plate, cover with film and put in the freezer for 10 minutes. Peel the horseradish and grate finely into a bowl. Grate, equally finely, the zest of the lemons and add. Squeeze the juice out of the lemons, strain and add to the mix, along with the sea salt, pepper and olive oil.
* Take the fish from the freezer and cut, skin side down, with a sharp knife into long, thin slices. Cut parallel to the board and avoid cutting into the skin. Arrange, without overlapping, on a cold plate. Pour over the marinade and serve with dry toast.
But probably the best way with them is the Hugh FW 'Gravad Max'. Sublime and from such an underrated fish;
River Cottage - Gravad Max
I would think you are much more likely to pick up something from a burger joint than from fresh fish which is also full of healthy stuff.
If you have not eaten seafood before try it in small quantities first just in case of allergies etc.