Healthy bounty of the sea

Mackerel are so remarkable they even have a cloud formation named after them, says Rachel Allen. Even better, they are truly delicious

Mackerel shoal in such glorious abundance that it is no wonder they appear so often in Irish myth, where they represent the bounty of the sea and nature.

They are beautiful fish, slim and delicate, with fantastic markings of light and dark in a distinctive pattern, almost as if they had been tattooed with indigo ink. So remarkable is this pattern that the fish even have a cloud formation named for them. A mackerel sky is one dappled with rows of small, white, fleecy clouds, and fishermen say it heralds change — ‘mackerel sky, mackerel sky, never long wet, never long dry’ goes the rhyme.

Along with being beautiful, mackerel must be one of the most preached-about of fish. We are endlessly told how sustainable, cheap and healthy it is, and, indeed, all of these things are true. But they are not always equally true!

The fat content of mackerel varies depending on the time of year; the fish stock up on food throughout the summer months, in preparation for the hard winters, and so are particularly high in fat in the autumn, and lean in the spring.

The extra oil they carry during late summer means they are especially delicious, but also especially healthy, with plenty of omega 3, protein and vitamin D. So now is the time to buy or catch them.

There are so many ways to eat mackerel. This is a strong-flavoured fish, so can take more robust flavours than you might expect. I love it with watercress, apple, or a rich herb butter. But really, the less you do to this firm and flavoursome fish, the better. It is so delicious straight from the sea, on a hot barbeque or simply grilled, then served with a cool, piquant cucumber and tomato salsa, right; a tangy anchovy sauce, far right; or whipped into a pate, above right. It is far better left to shine, with just a few accompaniments, rather than pressed into service with other, competing ingredients. I love it best of all when it is eaten within sight and smell of the sea.

“The less you do to this firm and flavoursome fish, the better”