Blame this post on some Twitter friends that assured me it would be interesting.
When you cure meat you have to learn a thing or two about ingredients that don’t come up much in regular cooking. I don’t know about you, but I never cooked much with dry milk powder, dextrose, or peculiar sections of beef intestines. I can say without a doubt that I never dealt with nitrites/nitrates before making moldy meat in my garage.
So I thought it might be kinda fun, in a food history geeky kind of way, to look at why nitrites/nitrates are used in meat curing, the effects and benefits they have, their health implications, and natural sources of nitrites. We will talk a bit about botulism poisoning too, just for giggles.
Nitrates have been used for a heck of a long time in meat curing. Early on people might not have known what helped meat keep its color, and last longer, but it was down to naturally occurring nitrates, an impurity in some salts. Slowly over the years knowledge developed along with food science, and today we know what we are dealing with.
What do Nitrites do in meat curing?
- Give cured meats an appealing even pink/red color
- Give that sharp “cured meat’s taste”
- Prevent botulism poisoning
Nitrates and Nitrites – what’s the difference?
When we talk about nitrites/nitrates, we are normally talking about Sodium Nitrite and Sodium Nitrate. There are other sources however (Potassium Nitrate, or Saltpetre) and we will talk about those later.
In short, quite a lot but also not that much. It is technically nitrITES that do the work. By “do the work” I mean give cured meat that lovely pink color, and sharp cured taste. Nitrite is also the delightful compound that helps prevent Cl. botulinum developing spores that gives us botulism poisoning – the most deadliest poisoning known to man.
So what do nitrATES do, and why do we use them? Well, consider nitrates to be a “slow release” form of nitrites. Bacteria in meat after a while will react with nitrate and create nitrITE. Since nitrite gets used up during the curing process, it is important to use some nitrates for meat curing that takes a while – like salami.
However, since it can take a while for the bacteria to start reacting with sodium nitrate, we should make sure that for meat curing, which can take many months, we use BOTH nitrite and nitrate to properly color the meat, give the tenderizing and taste effect, and also most importantly provide the required protection against botulism poisoning.
Wait.. did you say Botulism poisoning, that is serious right?
Yep. Sure is. I wouldn’t want to get it and I wouldn’t want anyone I know to get it either. Thankfully the chances of getting food borne botulism is extremely slim. From 1990 to 2000 only 263 people got effected by botulism, caused by 160 food borne events (source: http://www.medscape.com/viewarticle/489058_3).
If left untreated, botulism is most likely going to be fatal. Symptoms include difficulty swallowing, talking, breathing and double vision.
C. Botulinum spores are found in soil and water sediments all over the world. These spores are not dangerous until they germinate – which is when they produce the fatal toxin, Botulism.
For the spores to germinate they require the following conditions:
- mildly acidic environment
- an environment absent of oxygen
- warmth (40-15oF)
Now if we think about it, those are the EXACT conditions exhibited inside a sausage. Mildly acidic, thanks to the latic acid forming bacteria – no oxygen is available inside the salami. The meat mix is very moist, and we have added liquid to it too. We also ferment and air dry meat within the ideal temperature range for spores to germinate.
Given the information above, in my mind you would have to be somewhat crazy to cure salami at home without using some protection against botulism. YES, the chance of you catching botulism is extremely rare, however with something as serious as this, why take the risk?
Nitrites, in the correct quantities, prevent the formation of toxins from the germentation of the bacteria spores. USE THEM for all home cured salami products.
Incidentally, nitrates aren’t strictly required for curing whole muscle cuts. The bacteria can only exist on the exterior of the meat. This happens to be an oxygen rich environment, so there can be no development of the fatal toxin. If you take that meat with botulism on the exterior of it, grind it up, and stuff it tightly in to a casing, then those bacteria are now on the inside, in an airless environment. Best get out them nitrates.
Most food borne cases of botulism have either been caused by badly canned goods, or foods that have been incorrectly stored. There have been incidents where foods have been stored in air-tight containers and then not kept at a low enough temperature (remember, botulism likes 40-150F – so regular fridge temps of 36F are OK). There has been cases of botulism poisoning from the restaurant practice of storing chopped garlic (garlic can be a source of botulism) in olive oil. The olive oil creates that air free environment. I personally have stored chopped garlic this way, but always in the fridge.
OK, OK, you have sold me on nitrates.. where can I get the gear?
So, here is the thing. Nitrites and nitrates can be fatal when used in too high of a dose. Just 1/3 teaspoon of nitrITE could be fatal. You would need 1 teaspoon, perhaps more of nitrATE to have a similarly fatal effect.
Because of this it is incredibly hard for the general public to buy pure nitrite and nitrate. Large commercial curing plants mix up their own curing salts from salt and pure nitrites, but at home most people do not have scales accurate enough (or perhaps the math and food science knowledge) to do this safely.
Instead, us home curer’s can buy premade “curing salts”. These are certain pre-defined mixes that include regular salt, nitrite and nitrate. There are two different mixes available – CURE 1 and CURE 2.
CURE 1: A mix of 1oz of sodium nitrite (6.25%) to 1lb of salt. This is primarily used for curing products that are to be smoked – like bacon. Nitrate cannot be legally used in the craft of bacon making since when cooked at high temperature it can form cancer causing compounds. Since nitrite gets used up relatively quickly in the curing process, it is inadvisable to use nitrite only cures, like cure1, in long-term curing projects like salami.
CURE2: A mix of 1oz sodium nitrite (6.25%), 0.64oz sodium nitrate (4%) to 1lb of salt. This provides fast acting protection (nitrite) against botulism, and the slower release sodium nitrate to give longer lasting protection. This should be used in all dry cured salami that are to be cured over a long time, and can be used in whole muscle cuts for curing as well (mainly for color and flavor enhancement)
If we look at those percentages you would have to consume a lot of cure 1 or cure 2 to have a fatal effect – since the proportion of nitrite/nitrate is so low. You would literally have to be tied down, and have the stuff poured down your throat for a long time. Even still, it is incredibly important to store these ingredients high up on shelves, in tightly locked containers – way out of the reach of children.
Cure 1 and Cure 2, along with other meat curing supplies can be ordered from the following online retailers:
Butcher and Packer (http://www.butcher-packer.com/)
Sausage Maker (http://www.sausagemaker.com/)
Wait.. I heard that Nitrates aren’t safe – what’s the deal?
There has been some research done that show that when nitrates are subjected to high temperatures (600F or so) they can lead to the formation of nitrosamines which were cancer causing in lab animals. Because of that nitrates have been banned in the production of bacon – since most people fry those suckers at high temperatures till they are crisp.
A lot of studies have been done, and a lot of money has been spent on trying to see if nitrates and nitrites cause any health effects. The National Academy of Sciences have found nitrite does not directly harm us.
In fact, the amount nitrates/nitrites in meat is considerably tiny compared to those found in vegetables – especially those farmed using nitrate based fertilizers. Chances are also that if you grow vegetables at home in the soil, and your neighbor isn’t as organic as you – you are going to be eating a lot more nitrates. Especially also if you get your drinking water from a shallow well – like a lot of rural communities do in the USA.
You would likely consume more nitrate in a meal with a nice “healthy” helping of spinach than you would if you ate 1/4lb of smoked sausage.
Further to this, in 2008 a British study (British.. so it must be correct!) showed that consuming nitrate rich vegetables might be a good way to maintain a healthy cardiovascular system.
How much nitrite is dangerous? Stanley Marianski calculated that one would have to consume 14.3lbs of salami, in one sitting to consume a dangerous amount of nitrite. This doesn’t even take in to account that nitrite is used up (converted to inert nitric oxide) during the curing process, so most likely you would have to consume even more nitrite than that. Now, I love salami, but not so much to eat that much cured meat in one go.
I am a hippy and I want to cure meat naturally. Are there natural sources of nitrate I can use?
I can get with that too. Food grown without chemicals and pesticides are important to me, and I spend a good deal of my paycheck every month getting said produce from local farmers I know and trust.
The most widely used natural source of nitrates for meat curing is celery powder.
DON’T USE IT.
There, I said it. Here is the problem with it. There are absolutely no regulations or standards as to the amount of nitrate it contains. Even if you use the same amount in every salami you make, you could quite easily be adding too much or too little nitrate to your cured meats. Too little, and you might as well not bother. Too much can be dangerous.
Sodium Nitrate is a very simple compound (NaNO3 for you chemistry buffs) and the natural version, or lab made version is the same. No additional elements. Nitrate is nitrate.
Buy the proper cures for curing meat. Measure out your curing salts accurately, using a high precision scale. Don’t mess around celery powder.
The same incidentally goes for “saltpetre” or Potassium Nitrate as it is also known. This is one element in gun powder, but has also been used to cure meat for a long time (it was that impurity in some salt mines). The problem with saltpetre again is that it can contain a slightly varying amount of nitrate in it, and because it is used in gun powder, can be hard to get. Most people have now stopped using saltpetre in favor of sodium nitrate/nitrite based cures (Cure 1 and Cure 2).
If you are interested in learning more about the science behind meat curing, and the products involved – I highly recommend this book: (A fair portion of the information you see here was thanks to the great knowledge provided in its pages)