Origin
Sodium nitrite is the salt of nitric acid and is produced in a chemical reaction from sodium nitrate. E250 forms colorless to yellowish crystals. It is possible to dissolve the crystals in water under cooling. This solution then reacts alkaline. In nature, nitrates occur within the nitrogen cycle.
Usage
E250 is exclusively used as curing salt for meat preservation. As a food additive, sodium nitrite gives the meat an attractive red color and also prevents bacterial growth. The content of sodium nitrite in curing salt must not exceed 0.5%. E 250 is only used in a mixture with table salt. E 250 is also permitted for organic products.
Risks
E 250 or sodium nitrite is non-toxic as an admixture to table salt and at a low dosage of under 0.5 g. Cured meat should not be fried or grilled, as strong heating can produce so-called nitrosamines, which are carcinogenic. Infants under 6 months should on no account be given nitrate-containing water or vegetables, as nitrates prevent oxygen transport in the blood and thus lead to suffocation. Enzymes that could prevent this have not yet been formed in infants.