Italian cheese

Hard cooked cheeses come from curd cut to rice-grain size and heated to about 55 °C, which drives out the whey. You know the family by how it breaks: it does not slice, it splinters.

Pasta filata means spun paste: curd acidified to around pH 5, then stretched in near-boiling water until the casein realigns into parallel fibres. That is why mozzarella peels in sheets and aged caciocavallo has a vertical grain.

In blues the mould is an ingredient: Penicillium roqueforti in the milk, curd left unpressed, the wheel pierced so oxygen can reach it. Fresh cheeses skip ageing altogether, and ricotta is not cheese at all but reheated whey.

The numbers behind that. Milk sets between 32 and 38 °C, and the first real decision is how small the curd is cut, because a smaller grain exposes more surface and sheds more whey: rice grains for the cooked hard pastes, maize grains for semi-cooked wheels like Fontina and Asiago, which stop between 44 and 48 °C, walnut-sized lumps for gorgonzola, which is never cooked at all.

Cooking above 48 °C contracts the casein network and squeezes out the water still held between the strands, and it leaves only the thermophilic bacteria of the natural whey starter alive to break down the proteins for the next two or three years. What separates the families in the end is water, though the cut-offs are one convention among several: over 45 per cent is soft and everyone agrees on that, while the hard/semi-hard line is drawn at 40 per cent by some and at 35-36 by much of the literature, and mozzarella sits near 60. Spinning is the one step about calcium rather than water, since at around pH 5 the paracaseinate loses enough calcium to turn plastic, and in water at 80 to 90 °C the curd pulls like a skein.

That water figure predicts what you will meet abroad. A hard paste under 40 per cent survives a flight, a fortnight in your fridge and a grater; a fresh cheese at 60 per cent is a different food by the time it clears customs, which is why the mozzarella sold as a vacuum block was engineered to melt rather than to be eaten cold.

Parmigiano Reggiano carries a casein plate with a unique code, plus dotted lettering, the dairy's registration number and the month and year pressed into the heel. That number names who made it, not who packed it.

The fire brand is added at twelve months, and only after the Consortium's expert tappers work the rind and listen for cracks inside, though the certification that clears a wheel for branding is issued by the control body, OCQPR. Wheels that fail are stripped of their marks and sold nameless.

So aged 24 months printed on a shrink-wrapped wedge proves nothing. The oval IT-number-CE stamp is not a quality mark either: it is the EU identification mark under Regulation 853/2004, and on a wedge it often names the cutting plant. CE is on its way out, replaced by UE under delegated Regulation (EU) 2024/1141, with CE stamps allowed until 31 December 2028.

What the inspector actually does explains the mark. The examination runs in three stages. First a visual inspection of the outside of the wheel, then the tapping: a battitore runs a small hammer over the heel and the flat faces and listens, because a full even note means solid paste, a dull thud means a void or a split layer, and a boom means fermentation gas. Only where the hammer leaves doubt comes the third stage, a screw needle for the smell or a plug probe to pull a core. Wheels with minor faults become mezzano and are given parallel grooves cut right round the heel, so the downgrade travels with the cheese for life.

Minimum ages are written into the specifications and are the floor below which the name cannot be used: twelve months for Parmigiano Reggiano, nine for Grana Padano, five for table Pecorino Romano and eight for the grating grade, three for Fontina (whose PDO mark is applied from eighty days), seventy days for Bitto, sixty for Castelmagno, fifty for gorgonzola dolce and eighty for piccante, thirty-five days for Taleggio.

On an imported wedge most of this is gone. The rind is usually trimmed and the dotted heel lettering goes with it, so ask for a piece cut with the rind still attached, or buy from a counter that keeps the heel in view. The oval stamp on the back of the pack names the plant that cut and wrapped that lot, which abroad is frequently a warehouse in your own country rather than a dairy in Emilia.

Animal rennet comes from the fourth stomach of unweaned ruminants, and nearly every Italian PDO names it: calf rennet for Parmigiano Reggiano and Grana Padano, lamb rennet paste for Pecorino Romano.

That paste also carries lipases, which split milk fat and give Pecorino Romano and piccante provolone their bite. Change the rennet and you change the taste, not just the label.

The two non-animal routes are not the same thing. Fungal microbial coagulants (Rhizomucor miehei, R. pusillus, Cryphonectria parasitica) are native proteases that cut casein less selectively and leave bitter peptides over long ageing, so they belong on young cheeses. Fermentation-produced chymosin has the identical sequence and the same specificity as the calf enzyme, and does not turn bitter at any age. In the UK the block sold as Italian hard cheese is made this way; it could not carry the protected name whatever rennet it used, because it is made outside the delimited area. Rennet with no qualifier means animal.

Species and form both matter. Liquid calf rennet is almost pure chymosin: it cuts casein at a single site, which is why a wheel can run thirty-six months without turning bitter. Rennet paste is a different object: the whole abomasum of a lamb or kid, dried and ground with the curdled milk still inside it. Fiore Sardo specifies lamb; Provolone Valpadana uses calf for dolce and kid or lamb for piccante.

Thistle rennet is the interesting alternative rather than a compromise. Cynara cardunculus carries cardosins, which attack casein far more aggressively than animal rennet, and the result at two months is a paste you eat with a spoon and a clean bitter finish. It is written into Portuguese specifications (Serra da Estrela, Azeitão, Serpa) and survives in a few Sardinian sheep's cheeses. Two Italian PDOs allow it too, and for a vegetarian those two names are the answer. Pecorino delle Balze Volterrane, in Tuscany, requires vegetable rennet from wild thistle exclusively, and is the only Italian PDO made entirely without animal rennet. Asiago has explicitly permitted non-animal rennet, thistle included, since its specification was amended on 8 October 2020, which also dropped lysozyme.

Labelling is where your own country decides for you. In the UK cheese is routinely marked suitable for vegetarians, and the supermarket blocks sold as Italian hard cheese are made exactly that way; the protected name is closed to them regardless, since they are produced outside the delimited zone. EU rules never require the species behind the word rennet, so an Italian pack that says only caglio is animal. What is left for vegetarians abroad: the two PDOs above, acid-set dairy such as mascarpone, non-PDO cheeses that make the claim, and those style blocks.

Cling film is the fastest way to ruin cheese: sealed in plastic it sits in its own moisture, turns slick and tastes of the wrapper within days. Use two-ply cheese paper, or greaseproof paper in a loosely closed box.

Store it in the crisper drawer, the most humid and least cold part of the fridge, not the shelf above it, which is the coldest spot in the appliance.

Take it out forty to sixty minutes before eating: below 13-15 °C the fat is set and the aromas never lift. Parmigiano rind is food, so scrape it and drop it in soup, but wax, plastic and natamycin-treated rinds are not, and the label must say so.

Most Italian cheese abroad arrives vacuum-sealed, which changes the first ten minutes. Cut the bag open, wipe the surface and give it half an hour: the flat, faintly sulphurous smell off a freshly opened vacuum pack is trapped gas from weeks without air, and it blows off. Then wrap it properly and change the sheet every time you cut, because the used one has already taken up fat and moisture and is where mould starts.

In a static fridge the shelf directly above the drawers runs 0 to 3 °C, the middle shelves 4 to 6, the top 6 to 8, and the door 8 to 12 with a swing at every opening. A frost-free fridge holds one temperature throughout but dries hard, so the paper matters twice as much.

Freezing is defensible for a short list: hard paste in 200 g pieces, Parmigiano rinds, and low-moisture spun curd headed for an oven. Fresh, soft and blue cheeses do not survive it, because at -18 °C the crystals tear the protein network and the thawed paste weeps whey and goes grainy. Freezing does not age anything either: what goes in at twenty-four months comes out at twenty-four months. The plastic coatings on industrial provola and the coloured waxes never go into a pot.

Three or five cheeses, not nine: 80-100 g a head as a course, 40-50 g with drinks, chosen for contrast (one fresh, one aged hard, one blue, perhaps a washed rind).

Go mildest to strongest and reset with bread and water, not wine. Cut so every portion has both the centre and the part near the rind, and never slice Parmigiano: lever it into shards.

The rule that holds is that fat and salt fight tannin, so a young tannic red on a blue turns metallic. Two approaches survive: contrast, a sweet wine against a piccante gorgonzola, and regional concordance. Otherwise take sparkling.

Intensity is made by three things at once: the milk, which climbs from cow to goat to sheep, the months, and the kind of rind. An order that nearly always works is a fresh cheese, a young cow's-milk wheel, a sheep's cheese of a few months, a washed rind, and the blue last, because nothing tastes of much after it.

Three mechanisms do all the work. Tannins precipitate the proteins in your saliva and read as astringency; the fat and protein in cheese buffer some of that, but where heavy salt is added on top the sensation turns metallic. Residual sugar does the opposite and lowers perceived salt and bitterness, which is why a sweet wine holds up against a piccante gorgonzola where a young tannic red collapses. Acidity and carbon dioxide dissolve the fat coating and reset the palate, which is the whole reason dry Lambrusco sits beside Parmigiano.

Blues are the extreme case: their heat comes mostly from the short-chain free fatty acids the mould's lipases release (butyric, caproic, caprylic), while the methyl ketones carry the aroma, and that heat adds to the salt instead of cancelling it, so they want sweetness or no wine at all. Sauternes, a late-harvest Riesling or a tawny port all work where a Cabernet will not. If Italian bottles are hard to find the mechanism still travels: any dry sparkling wine handles a mixed board, an off-dry Riesling handles almost everything, and a Belgian dubbel does the job of a washed-rind wine.