Cure

To cure food means to preserve it with salt, usually with sugar and sometimes with nitrite, smoke or drying. Curing draws water out, firms the texture and makes food less friendly to bacteria. Bacon, ham, salami, salt cod, gravlax and many kinds of charcuterie are cured.

How to do it

A simple home cure for salmon (gravlax):

1. Mix equal weights of salt and sugar, about 50 g (1/4 cup) of each for a 500 g (1 pound) skin-on fillet, with chopped dill and crushed pepper.
2. Pack the mix over the flesh side.
3. Wrap tightly and put in a dish with a weight on top.
4. Refrigerate for 48 to 72 hours, turning once a day and pouring off liquid.
5. Scrape off the cure, pat dry and slice thinly.

Use fish that has been frozen first, or sold as safe to eat raw, since curing does not kill parasites.

Why it works

Salt pulls water out of cells and binds the water that remains, so bacteria cannot grow easily. Salt also changes muscle proteins, making the flesh firm and dense. Sugar softens the harsh salt taste and helps keep the texture tender.

Curing salts contain a small amount of sodium nitrite. Nitrite keeps cured meat pink, gives it its typical "ham" flavor, and protects against the bacteria that cause botulism, especially in sausages and in meat that is cured for weeks.

Common mistakes

• Using curing salt as table salt. It is dyed pink so you can tell it apart, and too much is toxic. Weigh it and follow the recipe exactly.
• Mixing up curing salt No. 1, for short cures and bacon, with No. 2, for long-aged meats.
• Leaving out nitrite from long dry-cured sausages that call for it.
• Curing at room temperature. Keep cures at 1 to 4°C (34 to 40°F) unless the recipe is designed for a curing chamber.

In recipes

"Cured" on a label means preserved with salt, often with nitrite. "Uncured" bacon is usually cured with celery powder, a natural source of nitrite. A quick cure of a few hours, as for fish, is close to a dry brine.