The traditional treatment given to fresh mackerel in Japan.
Mackerel sashimi by Leon Brocard (acme on Flickr)
There are a lot of great things to say about mackerel. It’s somewhat less overfished than, say, tuna or salmon, for one (although recently doubts have emerged about its sustainability). It also has the highest concentration of omega-3 fatty acid per serving of any fish we consume, which might make it heart-healthy.
But that high oil content poses a serious culinary hurdle. Unless you really, really like the taste of fish oil, mackerel can be a little overwhelming. When it shows up in my chirashi, I eat it only grudgingly, out of appreciation for the work of the chef and the sacrifice of the fish.
That said, there are ways to further alter the texture and flavor of mackerel. The traditional way to do that is to cure the fish briefly, using some combination of salt, sugar, and vinegar. The method described here is pretty basic, and should produce something similar to what you’d expect to get in a restaurant. More intense curing usually involves packing the mackerel with sugar for half an hour, then salt for an hour, with vinegar rinses after each stage.
Cold Wakame by Weddingraphy Studio, on Flickr
At its best, mackerel sashimi should be firm with a rich texture. The slight sweetness sweetness of the fat (enhanced by the curing method) should yield to a mineral, briney, but clean finish that pairs perfectly with citrus.
As for the wakame, that’s the variety of seaweed you’re used to seeing in a seaweed salad or floating in a miso soup. It’s most frequently sold dried, and needs to be both re-hydrated and washed. Ordinarily it’d get a longer soak, but using boiling water to wash it likely helps accelerate the process.
From a box sold in Martinez, California.
2 fresh mackerel
1 T. cucumber
Filet fish into sections. Lightly salt fish on both sides and let stand 30 minutes; after, pass fish through vinegar to wash off salt.
Peel thin skin off. Pull toward tail to peel off thick skin. Slice into 1/4″ slices.
Soak wakame. Drain. Pour boiling water over and drain again. Cut into eatable pieces. Put fish with wakame, cucumber slices, shredded ginger, lemon, soy.