Salt Peter and Health

So nitrates and nitrites are both harmless and ubiquitous. But is it really possible that eating nitrate-free meats could actually be more dangerous than eating meats that do contain sodium nitrate? The answer is yes.

One special property of sodium nitrite is that it prevents the growth of Clostridium botulinum. One of the most toxic substances known, Clostridium botulinum produces botulism, a paralytic illness that can lead to respiratory failure.
The botulism bacteria is peculiar bug because unlike most microbes, it actually requires an oxygen-free environment to live. Once it hits the air, it dies. So it tends to appear in canned foods, vacuum-packed foods, garlic stored in oil and improperly cured meats. It just so happens that sodium nitrite is especially effective at preventing the growth of Clostridium botulinum. 

Like sodium nitrite, sodium nitrate forms nitrosamines – human carcinogens known to cause DNA damage and increased cellular degeneration. Studies have shown a link between increased levels of nitrates and increased deaths from certain diseases including Alzheimer's, diabetes mellitus and Parkinson's, possibly through the damaging effect of nitrosamines on DNA. Nitrosamines, formed in cured meats containing sodium nitrate and nitrite, have been linked to gastric cancer and oesophageal cancer. Sodium nitrate and nitrite are associated with a higher risk of colorectal cancer. World Cancer Research Fund UK, states that one of the reasons that processed meat increases the risk of colon cancer is its content of nitrate. A small amount of the nitrate added to meat as a preservative breaks down into nitrite, in addition to any nitrite that may also be added. The nitrite then reacts with protein-rich foods (such as meat) to produce N-nitroso compounds (NOCs). Some types of NOCs are known to cause cancer. NOCs can be formed either when meat is cured or in the body as meat is digested.

Sodium nitrate may be used as a constituent of fertilizers, pyrotechnics and smoke bombs, glass and pottery enamels, as a food preservative and a solid rocket propellant. It has been mined extensively for these purposes.

Sodium nitrate is the chemical compound with the formula NaNO₃. This salt, also known as Chile saltpeter or Peru saltpeter (due to the large deposits found in each country) to distinguish it from ordinary saltpeter, potassium nitrate, is a white solid which is very soluble in water. The mineral form is also known as nitratine, nitratite or soda niter.

Sodium nitrate was used extensively as a fertilizer and a raw material for the manufacture of gunpowder in the late 19th century. It can be combined with iron hydroxide to make a resin.
Sodium nitrate should not be confused with the related compound, sodium nitrite. Sodium nitrate in the brine gives cooked corned beef its classic reddish color (without it corned beef comes out gray), and it kills botulism spores. Nitrate is actually changed to nitrite by bacterial action during processing and storage and nitrate itself has no effect on meat color.
It can be used in the production of nitric acid by combining it with sulfuric acid and subsequent separation through fractional distillation of the nitric acid, leaving behind a residue of sodium bisulfate. Hobbyist gold refiners use sodium nitrate to make a hybrid aqua regia that dissolves gold and other metals.

Health concerns

Nitrates and nitrites are chemical compounds commonly used in making cured meat products like bacon and hot dogs. A lot of ink has been spilled discussing the idea that nitrates and nitrites are bad for you, and food manufacturers have introduced all kinds of supposedly "nitrate-free" products to meet the resulting consumer demand.

But what you may not know is that not only are the fears over nitrates completely overblown, but these "nitrate-free" products can actually contain many times more nitrates than conventional products.

Not only that, but a truly nitrate-free hot dog would be much more likely to you sick than a conventional one.

Nitrates and Preserving Foods

Nitrates are used in curing, which is a broad category of techniques for preserving foods, mainly meat and fish, that involves the use of salt, sugar, or some form of dehydration. In each case, the goal is to make the food unattractive to the bacteria that cause food spoilage. This works because bacteria are tiny organisms that require, among other things, moisture, oxygen and food. Take away one of these things and they die.

Food Preservative

One of the earliest methods for curing food involved the use of salt. Salt prevents food spoilage through a process known as osmosis, whereby it basically sucks the moisture out of the bacteria's bodies, killing them by dehydration.

Sodium nitrate is a type of salt that happens to be a particularly effective food preservative. A naturally occurring mineral, sodium nitrate is present in all kinds of vegetables (root veggies like carrots as well as leafy greens like celery and spinach) along with all sorts of fruits and grains. Basically, anything that grows from the ground draws sodium nitrate out of the soil.

If this seems strange, remember that the word nitrate refers to a compound made of nitrogen, which is the single biggest component of our atmosphere. Every time you take a breath, you're breathing 78 percent nitrogen. The soil itself is loaded with the stuff. One of the things that happens when sodium nitrate is used as a curing agent is that the sodium nitrate is converted to sodium nitrite. It's sodium nitrite that actually possesses the antimicrobial properties that make it a good preservative. Interestingly, the sodium nitrate that we consume through fruits, vegetables and grains is also converted to sodium nitrite by our digestive process. In other words, when we eat fruits, vegetables or grains, our bodies produce sodium nitrite.

Nitrites and Botulism

 Given that sodium nitrate occurs naturally in foods like spinach, carrots and celery, as well as the fact that nitrite has never been shown to cause cancer, all the fuss about nitrates and nitrites might seem like typical media-driven hysteria. Moreover, the supposedly "natural" or "organic" versions of these products can contain many times more sodium nitrate than their conventional counterparts. But when you consider the increased likelihood of contracting botulism, it's actually the nitrate-free products that present the real health risk.