I've been thinking about writing about nitrates for quite some time, and I am finally getting around to doing it. I'll do my best to stay off of my soapbox; it truly annoys me to read the scare-mongering idiocy when it comes to nitrates. OK, got that off my chest.
To begin with, what exactly are nitrates? In this post I will discuss only sodium nitrate; potassium nitrate (saltpeter) and sodium nitrite are different and deserve their own separate consideration, so this discussion will comprise two or three posts. Sodium nitrate is a salt compound. Read the Wikipedia page about sodium nitrate; lots to consider when thinking about whether you want to eat anything with nitrates added.
Nitrates have traditionally been used as an additive in cured meats such as ham and bacon. For me the relevant question is, what is the function of nitrates in this context? Why are they there, and are they really necessary?
Here is the bottom line: In cured meats, nitrates act as an anti-oxidant. What does this mean? Well, you know when you open a package of ground beef, and the outside of the meat looks a little brownish-gray, and the inside looks nice and pink (assuming it's remotely fresh, of course)? That's because the outside has been exposed to air and oxidizes, turning it brownish-gray. You see where I'm going here... the nitrates, acting as an anti-oxidant, are there to preserve the COLOR of the meat. That's right, the presence of sodium nitrate is the reason why your ham is that pretty pink color.
Wait, you say, I thought the nitrates had something to do with the curing of the meat! That's exactly what I used to think, before I met David and started learning about it. I assumed that, having a chemical-sounding name, it must be a necessary part of the curing process (not that I had any idea what curing even meant at the time). So I went ahead and bought that bacon and that sandwich meat, assuming that I had no choice.
Here's the thing: No matter what anyone says, it's the SALT that preserves the meat, not the nitrates or anything else. In Italy, for example, they still make prosciutto the same way they've been doing it for hundreds of years: they bury the pork leg in a box of salt and let it sit.
Guess what, you DO have a choice about using nitrates, if you want to cure your own ham or bacon. On a tip from the butcher at our local QFC when we still lived in Seattle, I picked up a copy of a book published in the 1960s by the USDA for meat-industry professionals. Among many other interesting things, I learned that an acceptable substitute for sodium nitrate in cured meats is ascorbic acid. That's right, Vitamin C. Aha! We all know that Vitamin C is an anti-oxidant, right? So this makes a lot of sense, although these days what is written in charcuterie books defaults to the "you must add sodium nitrate" position.
One thing that really irritates me lately is the ways that the meat industry finds of getting around the labeling regulations about nitrates. Case in point: My husband David absolutely does not want to eat anything with nitrates in it. So, he recently brought home a package of Hempler's "uncured" bacon. The label clearly says, "No nitrates added.* Ah yes, the pesky asterisk. I finally found the very tiny printing that explained the asterisk: "Except those [referring to nitrates] naturally occurring in celery juice."
Huh? Excuse me, but if it looks like a nitrate and quacks like a nitrate, it's a nitrate! So I have gone back to curing our own bacon, something I hadn't done in at least a couple of years since we stopped raising pigs. I have 3 legs of prosciutto that I cured using only salt and spices and white wine, and I promise you it's safe to eat.
There are definitely specific health concerns when it comes to sodium nitrate, potassium nitrate and sodium nitrite; again I refer you to the Wikipedia page. Now that you know that the nitrate is there simply to preserve the color, you are in a position to make a more informed decision about whether you want to use it or eat it.
More exciting details coming in the next post! Stay tuned,and let me know what you think in the meantime.