Fermento
Cure #1
Cure #1 is salt with 6.25% sodium nitrite. Grams of cure are the meat weight times the target ppm, divided by 1,000,000, times 16. At 156 ppm that is 2.5 g per kilogram.
Calculator
Curing salt calculator
Cure #1 for a nitrite target, cure #2, salt by percentage and the weight to dry down to. Enter the weight of the meat.
The example is 1 kg of meat at 156 ppm. Change the weight first, then the target.
Salt Percentage
2.50%
Salt percentage relative to vegetable weight
Fermento saves the number with your batch.
Nitrite is toxic in excess, so weigh it and check the rule where you live. In the United States, 9 CFR 424.21(c) allows a quarter ounce of sodium nitrite per 100 lb of chopped meat, which is 156 ppm, and no more than 200 ppm of nitrite in the finished product. Great Britain, the EU, Australia and New Zealand set lower limits. Fermento is a calculator and a journal, and does not replace a validated recipe.
Cure #2
Cure #2 also contains sodium nitrate, which turns into nitrite slowly over a long dry cure. The calculator uses 0.25% of the meat weight, which is 2.5 g per kilogram.
Salt and weight loss
Salt is a percentage of the meat weight: 2.5% of 1 kg is 25 g. The target weight is the starting weight less the loss you dry to: 1 kg at 35% loss is 650 g.
In the app
Every cure keeps its weights
In Fermento a cure has its own timeline: the salt and cure you weighed, the weight each time you check it, and the temperature and humidity of the chamber.
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Questions
How much cure #1 per kg of meat?
2.5 g per kilogram gives 156 ppm of sodium nitrite, because cure #1 is 6.25% nitrite. The calculator works it out for any weight and target.
What is the difference between cure #1 and cure #2?
Cure #1 is salt with sodium nitrite, used for short cures. Cure #2 also contains sodium nitrate, which converts to nitrite slowly, and is used for long dry cures such as salami.
Is weight loss a safety check?
No. Weight loss is a quality target. For cured meat that is sold, food safety guidance works from salt, nitrite and measured water activity, so a producer needs a validated process.