What are Nitrites/Nitrates?
Nitrites give cured meats, like ham and bacon, the distinct color, aroma and flavor we love. Nitrite is also an antioxidant and has antimicrobial properties, so they provide a significant food safety benefits, such as preventing the growth of Clostridium botulinum which causes botulism, one the deadliest foodborne illnesses. They are considered a preservative because their antimicrobial properties also control spoilage bacteria, so cured meats have a longer shelf-life than fresh meats.
Processors may choose to use nitrate or nitrite in their recipes. Nitrate (NO3) is broken down by bacteria to nitrite (NO2) during the curing process. Nitrates are only used in the long cures, for products such as dry sausages or dry-cured hams, which will continually need nitrate to produce nitrite throughout the curing process. For most cured meats, modern meat processors simply add nitrite directly to formulation in very closely controlled amounts.
Natural Cure
Any processed meats labeled “natural” or “organic” cannot be prepared with nitrite because “preservatives” are not allowed in those products. As a result, there have been alternative curing processes that use natural sources of nitrate, such as celery juice or powder to create uncured products with a similar color and flavor to traditionally cured meats. The nitrate that is naturally within vegetables like beets and celery must be metabolized by certain types of bacteria and converted to nitrite. The nitrite then reacts with the meat to create the pink color and savory flavor characteristics associated with conventionally cured meats.
Confusion in the Labeling
Current USDA regulations require that meats cured with celery powder to be called “uncured” to distinguish them from conventionally cured products. Packages of meats cured with celery powder often say “No nitrates or nitrites added,” but also contain a statement “other than those which naturally occur in celery powder.” Some believe a more accurate way to describe the products would be to call them something closer to naturally cured, but still must comply with the regulations as written, which require them to be called “uncured.”
Nitrites and health
There is often a misunderstanding about the exposure to nitrites from meat. Of the body's exposure to nitrite, only 20 percent comes from food. Of that 20 percent, just 2 percent to 3 percent comes from processed meat. Nitrate is found naturally in green leafy vegetables such as spinach. Many vegetables are high in nitrate, which is then converted to nitrite when it comes into contact with saliva in the mouth. An estimated 80 percent of nitrite exposure comes from that produced within the body.
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