The reason saltpeter was in the Navy food was as a preservative, of course. Corned beef was a method of preserving meat at ambient temperature for an indefinate period.
The nitrates and nitrites (sodium and potassium) are what gives cured meats (hotdogs, salami, bacon, and especially ham and corned beef) that pink color. As such, consumption of them is ubiquitous; if they really had that effect, we'd almost all be uninterested.
When you buy nitrate for home curing, it's usually called "pink salt" or "Prague powder." You can make bacon and corned beef without them (I do), but it looks different.
Last edited by MacLir; 04-26-2012 at 10:16 AM.