Well, I guess as the 21st century rolls on we will all be bitten by Wikipedia eventually. Miraculously, I only just had my first experience. Luckily it wasn’t fatal.
In trying to figure out why my recent attempts at pastrami and salt beef yielded not an appetising pink, but rather a grey-coloured meat, I focused my attention on the recipe I was following which calls for 30g of Prague Powder #1 (aka “pink curing salt”).
I had made my own Prague Powder #1 using the proportions suggested by the Wikipedia page on curing salt. This states PP#1 is 93.75% table salt and 6.25% sodium nitrite OR sodium nitrate.
So 30g of PP1 would contain just 1.825g of nitrate or nitrite.
Didn’t seem like a lot. Perhaps that was the problem?
Yes, indeed I checked some other recipes and saw that Hugh Fearnley-Whittingstall, for example, suggests 50g of saltpetre. Saltpetre can be sodium or potassium nitrate, and I had always understood they were interchangeable in recipes. I figured that would be 800g of PP#1! Quite a discrepancy.
So I rather confusedly asked Tim Hayward who wrote the original recipe if he could figure out why things weren’t working out. It eventually became clear from our discussion and by reference to Google Books, that sodium nitrate is not, and never has been a component of PP#1.
The red colour in meat is formed when nitric oxide reacts with myoglobin. This is a multi-step process. Sodium nitrate (NaNO3) must be reduced to nitrite (NaNO2), a step dependent on bacteria. The resulting nitrite is reduced further to nitrous acid which goes on to form nitric oxide. This explains why you need much more sodium nitrate than you do sodium nitrite (presumably the reaction is slow, particularly with bacteria not wanting to grow in the acutely saline environment of a brine).
In this case, my mistake was fairly benign – sodium nitrate is much less potent than sodium nitrite and the end-result is simply grey meat. But it’s certainly made me think about other potential disasters which might result from an over-reliance on Wikipedia.
How did the mistake on Wikipedia happen?
It’s really not clear from the text. Wikipedia quotes two references for its claim:
The first is a broken link to a file entitled “USA Dry curing salt composition for meat products 2828212” on a server which doesn’t seem to be associated with any reputable food standards authority. Googling is no help tracking this article down.
The second reference is an article which doesn’t even mention prague powder #1 from the Jamaican Gleaner. The Gleaner was, incidentally, Bond and Fleming’s preferred Caribbean newspaper.
Who made the original edit?
Anyway, lesson well and truly learnt. Sodium nitrate is not the same as sodium nitrite, and sodium nitrate is not a constituent of PP#1. And don’t get your chemistry lessons off Wikipedia, or at least, not without consulting an independent reference.
Thanks Tim Hayward for the help! Next time I’ll just buy the pre-made cure from sausagemaking.org.
And I guess I should update the Wikipedia page, right?