Bronte Pistachio

Pistacchio Verde di Bronte DOP is a protected designation, registered in 2009, covering pistachios grown on the western slopes of Mount Etna in the Sicilian towns of Bronte, Adrano and Biancavilla.

One cultivar is allowed, the Napoletana, grafted onto wild terebinth, Pistacia terebinthus, known locally as spaccasassi, the stone-splitter, because it is the only tree that will root in the cracks of a lava flow. Without the terebinth nothing grows on the sciara at all.

The kernel is visibly different from the pistachios sold everywhere else. It is long and flattened rather than plump, emerald green right through to the centre rather than only under the skin, and wrapped in a red-violet membrane. Chlorophyll is high, unsaturated fat is high, and the aroma is resinous and almost balsamic.

Bronte calls it green gold, which is an accounting term more than a poetic one. The DOP area covers a few thousand hectares of hand-built lava terraces and produces a fraction of the million-plus tonnes harvested each year in Iran, the United States and Turkey. A tiny niche product sold into a mass market: that single fact explains most of the confusion around it.

Resinous, faintly piney, with an intense green nuttiness and almost no sweetness. Next to a Californian pistachio it tastes concentrated rather than mild, and the aftertaste is longer and slightly bitter, closer to a fresh almond than to a roasted snack nut.

Raw, the texture is dense and slightly waxy. Real Bronte gelato or paste tastes of the nut and looks dull khaki-green; the fluorescent green scoop in a tourist gelateria is colouring, not pistachio.

Roasting kills it. Above about 140°C the chlorophyll degrades, the green turns brown and the resin note evaporates.

Grind in short pulses with a cold blade. Pistachios are over half fat and turn to butter the moment they warm up; if you need a dry flour, add a spoonful of the sugar or flour from the recipe.

Do not roast them hard. A few minutes in a low oven is the maximum, and for gelato, creams and fillings they are used raw. Above 140°C you lose the green and the resin, the two things you paid for.

The Bronte household dish is pistachio pesto: peeled pistachios, olive oil, a little pecorino, a hint of garlic and pasta water, blended and tossed through paccheri or linguine, often with prawns or crumbled sausage. In pastry it fills cannoli and cassata alongside sheep's ricotta, becomes granita and gelato, and goes into torrone and biscuits.

Savoury: crush coarsely with breadcrumbs and lemon zest as a crust for swordfish or lamb; scatter over burrata; fold into meatballs; finish a pumpkin soup.

Buy peeled kernels only where colour matters. For pesto and for chopped garnish, shelled nuts with the skin on work just as well and cost far less.

More than half the weight of a pistachio is fat, and unsaturated fat oxidises. That single fact governs how it keeps, in every format. In the shell is the most stable: airtight, dark and cool, about six months. Shelled with the skin on drops to three or four months in the fridge in a closed glass jar. Peeled kernels are the most fragile at roughly two months refrigerated, and their colour fades before the flavour does.

For anyone buying half a kilo, the freezer is the real answer: vacuum packed they hold a year, and portions come out and go straight into a recipe without thawing first. What shortens all of these is an open paper bag left in a cupboard, the shelf above the hob and direct light. Once the oil has oxidised it reads as paint or wet cardboard on the palate, and that does not reverse; it comes through more clearly baked into a cake than eaten from the hand. An opened jar of cream goes in the fridge for about a month, and oil separating on top is normal, so stir it back.

Look at the shape first. A Bronte kernel is long and flattened, close to an almond in outline, while Iranian and Californian nuts are shorter, fatter and rounder. Then look at the colour at the cut rather than on the surface: Bronte is emerald right through to the centre with the purple-red skin still attached, whereas an ordinary pistachio is pale green just under the skin and turns yellow towards the core. The smell is intense and resinous, where salted roasted nuts from a bar smell mostly of salt and roasting.

The label must read Pistacchio Verde di Bronte DOP with the European logo and the Consorzio reference, and a careful producer prints the harvest year, which is always an odd number. Sicilian pistachio, Etna pistachio and Bronte-style are none of them the DOP. Price is the honest filter, since it costs several times what Californian or Iranian nuts do. On jars of cream, find the percentage printed straight after the ingredient name: plenty sold under the Bronte name contain three percent, legally and in small type.

Buy from Bronte itself. Several producers ship worldwide, and Italian specialists carry them: Gustiamo and Eataly in the US, Sous Chef and Italian delicatessens in the UK. Sicilian pastry suppliers sell paste and flour as well as kernels.

Check three things. The label must read Pistacchio Verde di Bronte DOP in full, with the EU mark. The harvest year should be stated and will always be odd-numbered. And the price must make sense: shelled Bronte below 30 euros a kilo does not exist, so 15 euros means Iranian nuts in a Sicilian bag.

Expect roughly 40 to 70 euros per kilo shelled (about 20 to 32 dollars a pound, or 35 to 60 pounds per kilo) and 70 to 110 euros per kilo peeled. In-shell is cheapest at 25 to 40 euros a kilo and keeps longest. For spreads, read the percentage printed beside the ingredient, not the name on the front of the jar.

Bronte, on the western flank of Etna, ideally in late September or early October of an odd-numbered year, when the pistachio festival takes over the town. The pasticcerie along the main street make granita, gelato, pistachio arancini and paste to take home, and several farms on the lava terraces run visits and let you join the harvest.

Adrano and Biancavilla complete the DOP area, and Maletto, strawberry country, is a few kilometres away, which makes for a good single day out.

Catania, an hour down the road, is where the nut shows up in the historic pastry shops and gelaterie, and the test is visual: real Bronte gelato is a dull, dirty green, never fluorescent. On the western slope between Bronte and Randazzo, trattorie pair pistachio with Etna Bianco and Nerello Mascalese.