I’ve had tentacles on the brain recently. Firstly, thanks to a very fine octopus pie I ate for breakfast on holiday (don’t knock it until you’ve tried it), and secondly because I’ve been working on perfecting a recipe for risotto al nero di seppia, the strikingly black dish beloved of the Veneto. Yet as I scrubbed yet another inky splash off the kitchen tiles last night, I realised I had no idea what the stuff actually was – and didn’t know much at all about the creature that had produced it.
In fact cephalopods, a family that includes cuttlefish, squid and octopuses, are still largely a mystery to science. Our last common ancestor, a flat worm-like creature more than twice as old as the first dinosaurs, was 600 million years ago; yet humans and cephalopods are the only animals to have, independently, developed high-resolution camera eyes.
Cephalopods are unusual amongst invertebrates, having larger nervous systems and greater cognitive complexity; the common octopus brain has 500 million neurons, giving it a comparable level of intelligence to a dog or a three-year old human; slightly startlingly, the majority of those neurons are in its six arms and two legs. That these same limbs, so very delicious chargrilled with a spritz of lemon juice, have the capacity to smell and taste as well as touch, is a detail that might give me pause next time I find myself sitting in a little harbourside restaurant with a laminated menu in my hand.
Back to that ink, though. Available in sachets from fishmongers and usually credited to the squid, it’s likely to have come from the more generously supplied cuttlefish. If you’ve ever tried to clean a cephalopod, you’ll know why the Norwegians call them blekksprut, or ink squirt: dark clothing is advised, as is taking the task outside. The ink itself is actually red, tinted by melanin, the same pigment that colours human skin, hair and eyes, but when concentrated can appear brown or, happily for the gothically inclined chef, black. It also contains melanin-producing enzymes, catecholamines, peptidoglycans, free amino acids and metals – none of which sound very tasty. (Fortunately the mucus ejected to create a cloud of ink is not part of the package.)
Yet tasty it undeniably is – chef David Tanis describes it as lending dishes an “indescribable complexity”, and he’s right –it’s hard to pinpoint the ink’s flavour. High levels of glutamic acid give it a savoury umami quality with just a hint of the marine, but its defining quality for me is its richness, which stands in perfectly for the usual half-pat of butter stirred into a risotto before serving. In this sense it resembles an egg yolk, but with a fifth of the calories (and few of the nutrients, though a compound called tyrosinase has been shown to exhibit “anti-tumour activity”).
But let’s be honest: delicious as it is, we cooks mostly value cuttlefish ink as a fancy food dye – there aren’t many black ingredients out there, which gives it a certain shock factor: black spaghetti or rice look so pleasingly dramatic on the plate.
Though traditionally it’s paired with seafood in a risotto or pasta dish, or made into a sauce for fish, in recent years squid/cuttlefish ink has popped up in a McDonald’s hamburger in Japan (for Halloween), as a pizza topping (again, Japan), in chocolate ice cream (Korea), and in cocktails across the US, including a vodka martini with caper brine that I’m tempted to try making at home. For the sake of the tiles, though, this is one martini I’ll certainly be stirring.