Curing Salt: What Pink Curing Salt Is, Cure #1 vs. Cure #2, and How Much to Use

Curing salt is what makes ham and bacon pink, but color isn’t its main job. It’s ordinary salt with a small, measured amount of sodium nitrite (and, in one common version, sodium nitrate too), and the nitrite is there mainly to control Clostridium botulinum, the bacterium behind botulism.¹ You’ll see it sold as pink curing salt, Prague Powder #1, Insta Cure #1 or DC #1. It’s dyed so nobody mistakes it for table salt, and it should never stand in for table salt.² Below: Cure #1 vs. Cure #2, how much to use, and the safety rules.

At a glance

What curing salt is

The two common types differ by one ingredient:

The nitrate in Cure #2 is there as a source of nitrite: USDA rules list sodium or potassium nitrate as a source of nitrite, allowed in cured meat products other than bacon.⁵ Formulas vary by maker, so use the percentage on your package in any calculation.

Not Himalayan salt. Curing salt is pink because it’s dyed. Pink Himalayan salt gets its color from traces of iron oxide.⁶ Don’t swap one for the other. Spice Jungle warns that its cure shouldn’t replace table or seasoning salt.²

What the nitrite does

The American Meat Science Association’s 2011 review of curing names Clostridium botulinum control as the main reason nitrite goes into cured meat. Nitrite also sets the cured color: nitric oxide from nitrite binds the iron in the meat pigment myoglobin and produces the pink of ham and bacon.⁷ It slows oxidative rancidity. And it adds cured flavor, though the AMSA review calls cured-meat flavor one of the least understood parts of nitrite curing.¹

You’ll often read that curing salt stops botulism by pulling water out of the meat and the bacteria by osmosis. The sources we read credit its anti-botulinum effect to the nitrite.¹⁷

History

Salting meat to preserve it is thought to go back as far as 3000 BC, according to the AMSA review and a 2022 review in Foods.⁷ Curing as such came from the realization that salt contaminated with saltpeter (potassium nitrate) caused the cured effect, and the Romans were adding saltpeter to meat on purpose for its red color and flavor. In the late 19th and early 20th centuries, researchers showed that nitrite, not nitrate, is what actually cures meat. The first USDA rules on nitrate and nitrite in meat came in 1925, allowing no more than 200 ppm ingoing.¹

Popular accounts credit the Sumerians with the first salted meat, say the ancient Greeks cured with nitrite-tainted salt, and name an inventor of “Prague Powder.” We couldn’t verify any of these, and none of the sources we read explains where the Prague name came from.

How much to use

How much curing salt you use comes down to how much nitrite it delivers, measured in parts per million (ppm) of the meat’s weight. US meat regulations cap ingoing sodium nitrite in chopped (comminuted) products at 1/4 oz per 100 lb of meat, and in dry-cured products at 1 oz per 100 lb.⁵

Computed: the standard Cure #1 rate. One ounce of a 6.25% cure contains 0.0625 oz of sodium nitrite. Spread over 25 lb (400 oz) of meat, that’s 0.0625 ÷ 400 = 156 ppm, the same as the regulatory 1/4 oz per 100 lb (0.25 ÷ 1,600 = 156 ppm). The Sausage Maker gives 1 oz per 25 lb of ground meat for its 6.25% cure and describes 156 ppm as the maximum ingoing nitrite for ground meat.³ In metric, 1 oz per 25 lb is about 2.5 g of cure per kilogram of meat, or about 1.13 g per pound. A 6% cure at the same rate, like Spice Jungle’s (1 oz per 25 lb), delivers 150 ppm.²

The limits come from the AMSA review’s table and the regulation itself; the bacon figures are the AMSA review’s summary of USDA rules. FDA rules for home curing preparations require directions that keep the finished meat at no more than 200 ppm sodium nitrite and 500 ppm sodium nitrate.⁸

Weigh the cure. You use very little, and a kitchen scale is the reliable way to hit these numbers. We found no published weight per teaspoon for curing salt, so we don’t give volume conversions.

Storage

Keep curing salt in its labeled package, away from ordinary salt and out of children’s reach. FDA rules require household packages of sodium nitrite mixtures to carry the warning “Keep out of the reach of children.”⁸ We found no shelf-life figure from a regulator.

Safety

Poisoning. Pure sodium nitrite is dangerous if someone mistakes it for salt. In 2002, five adults in Yonkers, New York, got sick with methemoglobinemia, a condition that impairs the blood’s ability to deliver oxygen, after eating food seasoned from a bag labeled “Refined Iodized Table Salt” that actually held 100% sodium nitrite. A former tenant who cured meat had stored it there. All five recovered.⁹ Spice Jungle says its cure is dyed so you can tell it apart from regular salt.² Store it separately from table salt.

Nitrosamines. Leftover nitrite can combine with amines in meat to form nitrosamines.⁷ US rules require bacon to contain 550 ppm sodium erythorbate or ascorbate to inhibit nitrosamine formation during frying, and the AMSA review identifies high heat above 130 °C, as in frying bacon, as the risk condition. The AMSA review says these measures and monitoring have essentially eliminated nitrosamine concerns in US meat and poultry.¹ A 2022 review notes that the International Agency for Research on Cancer has classified processed meat as carcinogenic to humans.⁷ That classification is of processed meat, not of curing salt as an ingredient.

Perspective on intake. The AMSA review notes that your body makes nitrite in significant amounts on its own, and that nitrite from food is small by comparison.¹ A 2021 review puts food additives at less than 5% of total nitrate and nitrite exposure.¹⁰

Curing salt and celery powder

Celery powder is used widely as a vegetable source of nitrite in natural and organic meat processing; starter bacteria convert its nitrate to nitrite.¹⁰ US labeling rules require cured-type products made without added nitrate or nitrite to be labeled “Uncured” and “No Nitrate or Nitrite Added.”¹¹ In 2020, USDA’s Food Safety and Inspection Service said it intended to propose banning those claims on products processed with any source of nitrates or nitrites, celery powder included.¹² See celery powder for more.

Substitutes and comparisons

We found no source naming a kitchen ingredient that does nitrite’s job. Celery powder only works because its nitrate gets converted to nitrite.¹⁰ See curing salt substitutes for what changes when you leave it out.

• Pickling salt, kosher salt and table salt
• Himalayan salt
• Celery powder