Strachitunt

Strachitunt is a raw whole cow's milk blue cheese from the province of Bergamo in Lombardy, DOP since 2014. The wheels are 4 to 6 kilos, 25 to 28 centimetres across, and 15 to 18 centimetres tall, taller than they are wide, which no other Italian blue is, and the quickest way to identify it.

The technique is the whole story. Curd from the evening milking is left to rest overnight; it cools and acidifies. Curd from the morning milking is fresh and warm. The two are broken by hand and layered alternately into the mould. Because they differ in temperature, acidity and moisture, they never fully knit together, and the fissures left between the layers are where oxygen reaches the interior. Wild moulds already present in the raw milk, the wooden hoops and the cellar air do the rest.

After about a month the wheels are pierced with long needles to open further channels. The veining that results is irregular and blotchy, pockets and patches following the seams between curds, rather than the even marbling of an inoculated blue.

Minimum ageing is 75 days. The specification requires raw milk and a predominance of Bruna Alpina cows, the historic breed of these valleys.

Sweeter and rounder than any blue its appearance suggests. There is a clear lactic sweetness underneath, the raw milk of mountain cows, with mushroom, wet stone and cellar behind it, and only a moderate blue bite at the finish. If your reference is Gorgonzola piccante or a mature Stilton, expect roughly half the punch and considerably more nuance.

The texture is the second surprise. It is soft but not creamy, and it crumbles along the seams where the two curds meet, so a slice breaks into irregular pieces rather than spreading. The whiter, less veined sections taste of fresh milk and yoghurt; the darker, veined pockets are savoury and peppery. One mouthful can contain both.

Because nothing is inoculated, no two wheels are the same, and the variation within a single wheel is part of the design rather than a fault. Buy a wedge that runs from rind to centre and taste across it.

Treat it as a board cheese first. Serve it at room temperature, an hour out of the fridge and not ten minutes, with the rind on, alongside chestnut or fir honeydew honey, walnuts and pears. Rye bread rather than white. Buy a wedge that runs from rind to centre so you can taste the range within it, because the range is the point.

In cooking, use it sparingly and off the heat. Over polenta taragna it melts unevenly, since the two curds behave differently, and that unevenness is more interesting than the flat result an inoculated blue gives. Stirred into risotto at the end, a small amount carries the dish. In a light cream sauce for stuffed pasta it works well, and on roast potatoes it goes on in the last few minutes.

The rule: never let it boil. Above about 70C the moulds turn bitter and the sweet-savoury balance that separates Strachitunt from gorgonzola disappears entirely.

The local seasonal dish worth copying: Martine pears poached in red wine, served with a piece of Strachitunt alongside.

Keep it in the vegetable drawer of the fridge, wrapped in greaseproof paper or in foil, never with cling film pressed against it, which smothers the moulds and produces an ammonia smell within days. Foil is acceptable for blues in a way it is not for other cheeses, because it slows the cut face drying. A wedge holds two or three weeks and it never stands still: the blueing keeps advancing even at fridge temperature, so it gets progressively sharper, the paste softens near the veins and the flavour that was mushroomy at the start moves towards pepper.

Blue green growth appearing on a cut face is the same mould that made the cheese, carrying on. Black, pink or furry growth, or a strong ammonia smell, is a different phenomenon, and there the date on the pack and the cheesemonger who cut it are the reference. It does not freeze: the paste separates and the veins turn bitter on thawing. Half an hour out of the fridge is the minimum and an hour is better, because a cold blue gives you only salt and heat.

The proportions give it away before anything else: a heel of 15 to 18 centimetres on a wheel only 25 to 28 across, which no other Italian blue has. The denomination mark and the producer code are stamped into the wheel itself, so a wedge should carry them. Cut, the veining has to be irregular and patchy, with blotches, pockets, greener zones and almost white ones, the pattern following the fissures between the two curds. Veins that are thin and evenly spread belong to an inoculated blue, a different cheese however good it is.

The paste is white to ivory, soft but not creamy, and next to gorgonzola it stays firmer and drier, crumbling along the seam where the two curds meet. The rind is thin and wrinkled, grey yellow, with the moulds that arrived on their own. The smell is cellar, raw milk, mushroom and undergrowth, and the bite stays moderate rather than fierce, the opposite of what people expect from a blue. In British and American shops the neighbours are Gorgonzola, Stilton and Roquefort, sharper and more uniform, and none a substitute.

This is one of the smallest DOP productions in Italy: fewer than ten dairies, a few dozen tonnes a year, so outside Lombardy it is a special order. In the US, look to Murray's, Formaggio Kitchen, Eataly and specialist importers, at roughly 28 to 40 dollars per pound when it appears at all. In the UK, expect 35 to 50 pounds per kilo through Italian specialists and serious cheesemongers, and expect to wait.

At the counter, check the veining. It should be irregular and patchy, with pockets and blank areas following the seams between curds. Regular, even marbling means an inoculated blue, which Strachitunt is not. The rind should be thin, wrinkled and greyish-yellow with natural moulds.

Ask for a wedge cut from rind to centre rather than a slab from one side, and ask the age: at 75 days it is sweet and lightly veined, at four or five months markedly more savoury.

In Bergamo the price is 22 to 32 euros a kilo, against 12 to 20 for gorgonzola DOP, made in tens of thousands of tonnes rather than tens.

The Valle Taleggio is reached from San Giovanni Bianco, in the Val Brembana, up a narrow road that threads through a gorge. The villages (Taleggio with its hamlets of Peghera, Sottochiesa and Olda, plus Vedeseta, Gerosa and Blello) hold a few hundred people each, and the dairies are the main economic activity and sell at the door.

Some producers still age cheese in natural rock cellars that hold the temperature and humidity the mountain provides free, and several will show them on request.

Bergamo is an hour away and is the practical base: the old shops of the Città Alta stock Strachitunt alongside the province's other protected cheeses, and Bergamo has more DOP cheeses within its boundaries than any other province in Europe. In October the city hosts Forme, a festival built entirely around them, which is the single best opportunity to taste several producers' wheels side by side.

Combine it with the Val Brembana: the Liberty-style spa architecture of San Pellegrino Terme, and further up the valley the alpine pastures that make Formai de Mut. Milan Bergamo airport is thirty minutes from the city.