The science of ‘ageing’ fish
Josh Niland loves fish. He loves how hard it is to get. He loves how most people find it difficult to cook. He loves that a lot of people have issues eating it, that they are put off by the smell or the texture. He loves the fact that even those who do like fish wouldn’t eat some parts, such as the head or tripe, or would turn their noses up at an appetiser made from fish eye balls. All of this makes his work more important, more vital. And it is why he has set himself a challenge. He wants to change our habits when it comes to fish: how it is sold and how we eat it. Since 2016, Niland has put his heart and soul into overturning those ideas at his 34-seat Sydney restaurant, Saint Peter, and at his shop, Fish Butchery, a couple of doors down. For those of you who can’t pop off to Australia, you can find him on social networks.He is also the author of the fascinating and acclaimed book Whole Fish Cookbook, described by the British celebrity cook Jamie Oliver as ‘a mind-blowing masterpiece’, and which René Redzepi and Grant Achatz have labelled as ‘inspiring’. How long should fish be allowed to age so that it is at its peak? Can we talk about long-aged fish in the same way we do for meat? Josh Niland has been asking himself that for years. He is passionate about dry-ageing fish and is on a quest to find the answer. An answer he found by keeping fish in a low-temperature, low-moisture environment to find its ‘sweet spot’.
He continues to probe which species it works best with (Spanish mackerel, Atlantic horse mackerel, sea bass, tuna, swordfish, etc.), and how far he can take the ageing process (20, 25 days? Or longer?). Ageing means a loss of water, a change in texture, and much better flavour. The ageing time is different depending on the kind of fish. Until a few years ago, it was unimaginable to go against the unwritten rule that fish should be eaten as fresh as possible. However, this ageing technique has smashed that rule. Niland has boyish features, and watching him work is to behold a show. It is a work of art to see how he ritually treats the fish.
He begins by taking long strips of scales, then turns his attention to the head, tenderly handles the guts, and then prepares the fillets... In his ceaseless search for using as much of a fish as possible, he is also working on finding ways to use its offal. ‘I’ve yet to master the gall bladder,’ he told The Guardian a few months ago. People only use about 40% of a whole fish, at Saint Peter, Niland uses 90%. It is clear to him that if almost everything from a cow, sheep or pig can be eaten, so why not from a fish? ‘Anything you can do to an animal, let’s do to a fish,’ he declares.