Formai de Mut

Formai de Mut dell'Alta Valle Brembana is a semi-cooked raw cow's milk cheese from the upper Brembo valley, north of Bergamo, inside the Orobie Bergamasche park. Wheels weigh 8 to 12 kilos, measure 30 to 40 centimetres across, and have straight or very slightly concave sides, with a thin straw-yellow rind that greys and browns with age.

The denomination covers two cheeses that share a name. The valley version is made all year in dairies along the floor of the Val Brembana and is the everyday table cheese of the area. The monticazione version is made only during the summer transhumance, from 1 June to the end of September, up on the pasture, from milk worked minutes after milking. Alpine wheels carry their own mark and usually the name of the individual malga that made them. They are a small fraction of total output and a genuinely different cheese, not a marketing tier.

Minimum ageing is 45 days. Most of what is sold sits between two and six months; alpine wheels take a year and more without tiring. The milk is raw and whole, with no skimming and no pasteurisation, and the rennet is calf.

Production is small, a few hundred tonnes a year against the tens of thousands of the industrial names, which is why the cheese is effectively unknown twenty kilometres outside its valley, let alone abroad.

The valley version tastes of sweet milk, butter and cooked hay, with a nutty finish and a clean, gentle acidity. The texture is the point: firm, elastic, faintly springy, with tiny scattered eyes. It is a friendly cheese, easy to eat in quantity, closer to a young Alpkäse than to anything sharp.

The alpine version is a different proposition. Milk from cows eating high-summer pasture carries herbs into the cheese, and it shows as a green, almost mentholated top note over the butter. At six months to a year it becomes savoury and deep, with hazelnut and dried-mushroom notes and a long finish that turns faintly meaty.

Across both, the register is sweet rather than salty. If you know Fontina Val d'Aosta, start there and add firmness; if you know Comté, start there and remove some of the salt and the brothy weight. Nothing about it is challenging: the reason to seek it out is the pasture, not the punch.

Young Formai de Mut is a melting cheese. The local dish is polenta taragna bergamasca: buckwheat and cornmeal polenta, cooked long, with cubes of cheese and plenty of butter stirred in off the heat until the whole thing turns glossy and pulls in short strings. It also works grated over casoncelli, the local stuffed pasta, with brown butter and pancetta, and in a savoury tart with potatoes and onion.

The rule that matters is heat. Above about 70C the fat separates and you get a rubbery mass that nothing recovers. Add it off the flame, or melt it in a bain-marie with a splash of milk and an egg yolk for a mountain fondue to pour over boiled potatoes.

Past six months it becomes a board cheese. Serve it in shards at room temperature with rhododendron or chestnut honey, walnuts and pears. Year-old alpine wheels are strong enough to grate in small quantities over barley soup or risotto, where the herbal note carries the whole dish.

Fridge, vegetable drawer, wrapped first in a barely damp cloth and then in greaseproof paper. A young piece holds three or four weeks that way and an aged one about two months, while a vacuum pack runs to its printed date, which is the dairy's reference. Cling film laid straight on the cheese is the worst option available: the paste cannot breathe, the rind softens and the cut face turns slick within days.

What the cheese does over those weeks is lose water from the outside in. The cut face dries, hardens and darkens slightly, and a millimetre scraped off with a knife gets you back to the paste; as moisture leaves, the salt concentrates and the flavour sharpens. Dry white or green bloom on the rind lifts with a cloth dipped in vinegar or white wine, while anything else on the surface is a question for the shop and the date on the label. Whole wheels live in a cellar at 8 to 12 C with high humidity, turned every fortnight. Freezing is not for this cheese: it tears the semi-cooked paste and leaves it mealy.

The heel of a certified wheel carries the denomination mark stamped into it with the dairy code, and summer mountain wheels add the alpeggio mark, usually alongside the name of the hut written or cut by hand. That is the first thing to find, because ten euros a kilo separate the two. The paste should be compact and elastic, ivory in young wheels and straw-coloured with altitude and age, with sparse, tiny eyes of the kind Italians call partridge-eye. Large irregular holes are a sign of an odd fermentation rather than a feature of the type.

The rind is thin and even, never thick and cracked, and a cut piece should neither crumble nor bead with whey; a sweating wedge has been under cling film too long. The mistake worth avoiding in the valley itself, and on any counter that stocks both, is Branzi. It comes from the same Val Brembana, it is made all year, the wheels are bigger and the paste softer, and it is a fine cheese, but it is not DOP and it costs less. Sold as Formai de Mut, it is trading on the confusion.

This is a genuinely hard cheese to find outside Lombardy. In the US, look to specialist importers and cheese counters that carry Italian alpine wheels: Murray's, Formaggio Kitchen, Eataly and the better regional cheesemongers occasionally list it, most often in autumn when the summer alpine wheels come down. Expect roughly 22 to 35 dollars per pound, more for a named malga.

In the UK, Italian delicatessens and alpine-cheese specialists are the realistic route, at about 28 to 45 pounds per kilo. Neither market stocks it consistently, and it is worth asking a good cheesemonger to source it rather than hunting shelves.

When you find it, check two things: the denomination mark branded on the side, and whether the wheel is valley or monticazione. The alpine version costs ten euros a kilo more at source and should not be sold at the valley price, or bought at the alpine price without the mark. Also, do not accept Branzi as a substitute sold under the same name: it is a fine cheese from the same valley, but it is not the DOP and it is cheaper.

Branzi is the natural base: the village dairy has been working for over a century, and the road onward serves Carona, Foppolo and Valleve. Piazza Brembana, Valtorta, Ornica and Mezzoldo are the other villages where the cheese is bought where it is made.

In summer, walk up to the malghe of the upper valley or eat at the Orobie mountain huts, where the cheese arrives on the board a day after leaving the mould. The Passo San Marco above Mezzoldo is the old Venetian road over the ridge into the Valtellina, and it crosses pastures that also make Bitto DOP.

Bergamo itself is forty-five minutes from the valley mouth and the obvious base for anyone flying into Milan Bergamo airport. The old shops of the Città Alta stock both versions and will let you taste them side by side, which is the fastest way to understand the cheese. In October the city hosts Forme, a festival built around the province's protected cheeses, since Bergamo has more DOP cheeses within its boundaries than any other province in Europe, and this is where they are all in one place.