Unsalted butter

Yes. Add salt separately: as a rough guide, use about 1.5 g fine salt for every 100 g of unsalted butter, then adjust for the recipe. This gives you more control over the flavour, especially in cakes and biscuits.

Butter’s milk solids brown and then burn quickly over high heat. Cook over a moderate heat, or use clarified butter for hotter frying; for a simple alternative, combine butter with a little oil.

Keep it wrapped in the fridge, away from strong-smelling foods, and use a clean knife to prevent crumbs getting into it. You can freeze it in its wrapper or an airtight container; thaw it in the fridge before using.

Use an equal weight of baking margarine or a plant-based block made for baking; soft tubs can make cakes spread or turn greasy. If a recipe relies on butter’s flavour, the result will taste different.

It works in shortcrust pastry, scones, mashed potatoes and sauces such as beurre blanc, where you can control the salt yourself. For a quick finish, melt it with chopped parsley and lemon to spoon over vegetables or fish.

Not necessarily: “butter” may refer to salted butter, while unsalted butter has no added salt. Unsalted butter has about 14 mg sodium per 100 g, compared with about 1,010 mg in salted butter.

Yes. It is high in vitamin A: a 100 g portion contains 927 µg. Butter is also mostly fat, including 60 g of saturated fat per 100 g.

A small amount can be kept covered in a clean butter dish for a short time so it softens for spreading. Keep the rest chilled, and discard butter that smells rancid or has become contaminated with crumbs or food.