Ingredient

Mascarpone

Mascarpone is cream that has been gently heated with a little acid until it thickens. There is no culture, no rennet, and essentially nothing in it but cream — which is why it is so rich, so mild, and so much closer to clotted cream than to any other cheese it sits beside in the chiller.

What it is, and why it is not cream cheese

Mascarpone is made by warming cream and adding an acid — tartaric acid, citric acid or lemon juice — until the protein coagulates enough to thicken it. It is then drained. That is the whole process, and it takes hours rather than days.

Cream cheese, by contrast, is made from milk and cream cultured with bacteria over a longer period, which produces lactic acid and a distinct tang, and it is usually stabilised with gums.

So the differences are real and predictable. Mascarpone is far higher in fat, typically around double cream territory. It is noticeably less tangy — sweet and milky rather than sour. It is softer and looser, spoonable rather than sliceable. And it melts into a sauce where cream cheese tends to sit in it.

The practical consequence: they are not substitutes for each other. Mascarpone in a New York cheesecake gives you something that will not set properly; cream cheese in a tiramisu tastes sour and wrong.

Why it splits, and how to avoid it

Mascarpone is essentially concentrated fat held in a delicate protein structure, and that structure is easy to break. It fails in two directions and both are common.

Over-beating is the usual one. Whisk mascarpone hard, particularly with a machine, and you do to it what you would do to double cream taken past stiff peaks: the fat globules clump and it turns grainy and curdled. It happens fast and it is not reversible.

Temperature shock is the other. Cold mascarpone beaten into a warm mixture, or warm mascarpone chilled abruptly, will separate.

The rules that follow are simple. Bring it to cool room temperature first — twenty minutes out of the fridge. Loosen it by hand with a spatula before anything else touches it. Fold rather than whisk wherever you can. Stop the moment it is smooth, and never keep going "just to be sure". And in a hot dish, add it off the heat.

What to use it in

• Tiramisu, which is what most of it is bought for. Beaten with egg yolk and sugar, folded with whipped cream or beaten white, layered with coffee-soaked sponge.
• Stirred into risotto at the end, in place of or alongside butter, which gives an exceptionally creamy finish.
• In a pasta sauce, off the heat, with lemon and black pepper, or with spinach and nutmeg.
• Folded into mashed potato, which is extravagant and very good.
• With fruit, sweetened with a little icing sugar and vanilla, as the simplest possible dessert.
• In cheesecake, alone or blended with cream cheese for a softer, richer, less tangy result.
• In frosting, where it makes a less sweet and less claggy alternative to buttercream — though it must be kept cold.
• Whipped with cream, half and half, which stabilises it and makes it easier to handle.

Substituting it

Nothing is exact, and what works depends on whether you need the fat or the texture.

Cream cheese plus double cream

Roughly three parts cream cheese to one of cream, beaten smooth. The standard substitute. Tangier than the real thing.

Clotted cream

Closest in fat and richness. Thicker, and it has a cooked flavour that suits some dishes and not others.

Crème fraîche

Similar texture, considerably more acidic. Fine in a savoury sauce, wrong in a tiramisu.

Ricotta

Much lighter and grainier. Not a substitute where richness is the point — see ricotta.

Making your own

Double cream warmed gently and stirred with lemon juice until it thickens, then strained overnight through muslin. Genuinely easy, and cheaper than buying it.

Keeping

A few days once opened. It is a fresh, unpreserved, very high-fat product and it does not last.

Common questions