The Quest for Nitrite Free Curing

The Quest for Nitrite Free Curing

18 January 2020


I have been involved in the curing industry for almost 15 years now and during this time I fell in love with one of the most enigmatic salts from antiquity called nitrites. Over the years I have written extensively on the development of meat curing (Bacon Curing – a Historical Review). I tracked its development from millennia ago in Salt – 7000 years of meat-curing and Nitrate salt’s epic journey: From Turfan in China, through Nepal to North India. Ancient developments came together for me in the article And then the mummies spoke!.

Despite the fact that I am convinced that current processing methods of hams and bacon do not pose any health rish for consumers, the demand for nitrite free bacon is not going away. Bacon and ham have always been a product for the people and whatever our personal views on the matter, the clear and growing consumer demand must be catered for.

Over the years I have seen spice companies acting with great dishonesty. They develop curing mixes that they claim accomplish meat curing without nitrites. The way they did this was by using plant extracts which are naturally replete with nitrate. Through bacterial reduction, they achieved the conversion of nitrates to nitrites which was then sold as a “natural” curing agent due to the fact that no synthetic ntirite was added. They circumvented food labeling legislation by not adding synthetic nitrite. In reality they still add nitrites to curing brines.

I have friends from around the world who build their brands on the claim that it is nitrite free and having investigated those claims, I can confidently say that they definitely add nitrites to curing of meat. It is an embarrassment just waiting to be exposed!

The Spanish Case

A Spanish producer launched a new curing system in the early part of the 2010s. They claim great results and that only plant and fruit extracts are being used. Despite this being a step in the right direction, several aspects of the development do not sit well with me, in particular the fanatical secrecy surrounding the product. Pardon my skepticism, but I have been disappointed so many times by European spice producers that my initial reaction is to be vary cautious. This feeling was further strengthened when I saw the reluctance of the producer of the brine to disclose the ingredients and the methods of action. Are they only protecting proprietory information or are they hiding something? I am infuriated by spice companies who refuse disclosure when as producers, we are held to very strict label declarations and transparency in process descriptions. More than that, such declarations have proven to be in the best interest of consumers, yet, spice companies repeatedly see themselves as “above the law” in this regard.

We were preparing for sausage trails today and a published interview with the CEO of the Spanish producer of the brine milled through my mind. I do not understand the secrecy! Certainly there is a place for protecting proprietary information, but when the way it is being done goes against the food legislation governing all of us, it does not sit well with me. If the entire commercial viability of the approach is based upon complete secrecy, how do they expect to win the hearts and minds of the very consumers they are trying to reach out to by its nitrite-free curing brine. How will “trust me, I’m a doctor” in terms of this product be different from “trust me when I say that nitrites is not really bad for you?”

In the absence of information, people speculate and since the company is creating an enviroemt where people will speculate, let me also “speculate”. I asked the question how I would have done it if I had to copy what they did. For starters, remember that my approach is predicated on science. I have extensively looked at the curing reaction in Reaction Sequence: From nitrite (NO2-) to nitric oxide (NO) and the cooked cured colour and the colour of fresh meat in Difference between Fresh Cured and Cooked Cured Colour of Meat. There is a fundamental reason why the world works the way it works and understanding nitrite curing is intimae associated with our most fundamental understanding of the universe. In Fathers of Meat Curing I review the key developments.

Let us first look at what they get righ and wrong before I try and replicate what they did.

– What they get right.

The company claims that they address Listeria spp (broad spectrum), Listeria
monocytogenes, E Coli H157, and Clostridium spp (broad spectrum). The organism responsible for the existence of the meat curing industry is Clostridium Botulinum. (Clostridium Botulinum – the priority organism) and the fact they address it in their research is significant. The curing brine is effective against Clostridium Botulinum is very important. Personally I would like to know how effective it is against damaging the spore and preventing its viability. I am not sure if the study looked at that. If not, I would ask for that detail. I wonder about the no nitrites claim and if they don’t use nitrates which are rapidly reduced to nitrites and then nitric oxide. Taken at face value, this is, however, something they get right.

– Questions about antimicrobial efficacy

Challenge tests were performed where the brines efficacy was tested against sodium nitrite and compounds such as sodium nitrite plus sodium erythorbate, and a control with no antimicrobial. They claim to have demonstrated that their product performs equally well against listeria mono and Clostridium botulinum. Still, my reservations stand. Do they match the effficasy against Clostridium botulinum of nitrites in every regard?

In reviewing references to the brine, I found a claim that it its anti-microbial activity is especially effective if used with dehydrated lactic acid. Dehydrated lactic acid will itself be effective against amongst other, Listeria Monosytogenes. The one that worries me is still the efficacy against Clostridium. The claim is that its efficacy is due to traditionally processed Mediterranean fruit and spice extracts. What bothers me is that through the ages of meat processing, the producer claim that extracts were used which until now has been hidden from science. There is a lack of understanding of the experimental character of the meat curer who would, over thousands of years, if not millennia, certainly have stumbled upon these miracle substances and have incorporated it into his or her processing techniques long ago. If a mix of spice extracts were effective against Clostridium B and its spores, I am one hundred percent convinced that this would have been known. The chances are that those extracts would, in high dosages been toxic to us.

A further claim is made that these extracts are high in naturally occurring compounds with antimicrobial and antioxidative capacities. The antioxidative claim is interesting. There are indeed a number of extracts which claim exactly this. However, what is the role of these antioxidative agents in meat curing. The context of the claims seems to point to pathogen eradication when in actual fact its role is in the prevention of fat rancidity and the development of off flavours. So, the claim may be correct, but the application seems exagerated.

– Questions about colour

The claim is made that these extracts are responsible for the meat flavor as well as its typical reddish color and pathogen protection, without the risk of nitrosamine formation. It is the claims about antimicrobial efficacy of the compound that is the most worrying and second to this, is the claim about the fact that it imparts a cured colour to the meat.

The most fundamental question will be this – is it causing the meat to change colour or is it imparting a colour to the meat. Is it an external colour which is imposed upon the meat or is the meat itself changing colour as it does in the case of nitrite curing?

Identifying which one it is is very simple. Let me walk you through it. For the meat to change colour, it is a reversible reaction (before heat setting). During curing, meat often turns brown due to oxidation, just to turn the regular pinkish/ reddish colour of cured meat. It the meat is able to go from brown to pinkish/ reddish, back to brown and again back to pinkish redish, you are dealing with the meat changing colour.

Secondly, look at the fat. If the fat inside the meat change colour (to pink for example), it is an external colourant applied to the meat and whether this is a plant extract or not, it must be approved as a meat colourant by the relative legislative body.

Look for an accumulation of coloured brine. Especially in pork belly (streaky bacon) this will be noticeable where the injected brines are often trapped between the horizontal layers of fat and connective collagen. If an external colour is used, the brine pockets will display a brighter colour than in the meat surrounding it. It is one of the many reasons why it is not advisable to use a colourant in ham or bacon injection.

No plant extract without nitrogen will cause the meat itself to change colour. This is one of the laws of nature. There are colours imparted to long term cured meats which forms a purplish colour, but as far as my knowledge goes, the exact mechanism is not well understood and despite a considerable effort, scientists have not been able to replicate this effect in short cured hams and bacon.

The molecule responsible for the cured colour of meat is Nitric Oxide. Without Nitric Oxide being produced somehow by the magical concoction of spice extracts, the meat itself will not change colour and a colourant will be used. The fact that this may be a natural colourant is then a matter for consumers to decide whether they are satisfied with this, but that the meat is not “cured” in the traditional sense of the word is a fact. At best you can call it fresh coloured meat.

If, however, the meat itself change colour, this can only happen through the action of nitrogen which means that at some point, nitrites were involved which formed nitric oxide through a chemical reaction. Despite the claims to the contrary, it still can not be ruled out and the saying remains true that the onus to prove is on the party who makes the claim. Where this cure is being used, look at the ham or bacon and evaluate it yourself. If the meat itself is changed, there is a problem in what the company declares!

– Questions about flavour

If the plant extracts impart flavour to the meat and it is not natural, does this mean that meat prepared in this way is “flavoured meat?”

How Would I have Done it?

I did not speak to anybody about the production of this product, but as an interesting question, while I was working today on sausages, I wondered how I would have done it. For background to this, read my article, Regulations of Nitrate and Nitrite post-1920’s: the problem of residual nitrite.

For starters it would have been very easy if one used nitrates. I see no mention of it in their literature. If I had to guess how the cure is made, I would say they possibly could be using reduced amount of nitrates but my guess would be that if this is used, residue nitrites are disposed of during the curing process. How to convert the nitrate quickly to nitrite would have been the challenge. I would have used techniques developed through the celery and beetroot juice developments where nitrates in plant extracts were converted to nitrite. In salami manufacturing, the use of starter cultures have become so commonplace that it will be easy to impregnate the brine with bacterial cultures who can achieve the conversion quickly. I would have elevated the levels of ascorbic acid, to ensure that nitrites are rapidly converted to nitric oxide which achieves the cure. I would add plant extracts to bolster the reduction to NO, to add flavour, to assist in the colour and to confuse the issue. Paprika, red chili’s, red pepper, etc are good colour enhancers especially for a darker, reddish colour. In terms of micro I would rely on nitrite, nitrate and the anti microbial action of the plant extracts which I would add. I would set out a tight schedule in terms of how long the product must be cured before the important test is done for nitrites.

From correspondence with the company, I learned that they say that the meat itself does not change colour which means that they are not using nitrate, but in the absence of full disclosure, how do we know? Who says that the statement is not purposefully vague? The fact that there is no detectable residual nitrites does not necessarily mean that no nitrites were added. It only proves that the usage of ascorbate was successful. I wonder why even test for residual nitrites if none were added in the first place. However, despite my own scepticism, lets take them at their word. Lets assume that nitrates are not used. Like them, one of the options I would use would be to rely on plant extracts. There are, however, other conceivable techniques that could be used aslo.

Supporting Correspondence

Remember that I have no knowledge if this is actually how the curing brine is being made. I discovered one bit of information that I can use to get some idea if I am on the right track or not.

I looked at mail communication that was made public related to the product under the access to information law. In this communication, regulators are asking questions which I echo.

The company has to make known the materials used (more detail than edible spice and fruit extracts) and if they claim that the meat colour is changed itself, show how by which mechanism this is achieved. Failing which, it is an external colourant and must comply with colouring legislation. Failing such disclosure is against the letter and spirit of our food laws. (Refer to my article Concerning Chemical Synthesis and Food Additives)

The question is asked as to “what kind of processes are being used e.g. physical, chemical or microbiological for the extracts? How many steps are there in the extraction process?” Any processor are asked to show this kind of detail in its own factory and the fact that a spice supplier believes they are, as it were, above the law in this regard is a concern.

Another good question that came up was for a “simple flowchart”. The company claimed, I assume, that “simple ethanol water extraction, using traditional methods of extraction and no selective physical or chemical extraction of constituents” are used. The legislature ask for “further detail, for example, and ask if the extract is a standardized product? How do you prevent variation?” Again, these questions would be asked from us who use the product in processing and the company has to comply.

The all important question is then asked related to the “active component or components that are being used as a substitute for nitrite/nitrate preservatives to prevent the growth of harmful microorganisms and/or increase shelf-life? If this is considered commercially sensitive information can you describe how it kills or prevents the growth of microorganisms? These are the same questions I have raised above. Meat science is not an isolated discipline being pursued in dark corners any longer. It is done at almost every university and high profile meat institutes and if another product was available for curing meat apart from nitric oxide, television programs would have been made about the discovery and every scientist on earth would have known about it.

Related to the colour of the meat, it seems as if the company stated that the meat does not actually change colour. The legislator asks, “Does any component impart a colour change in the pork meat?” The statement is then made that the company has said that “no component used imparts a colour change in the pork meat.” This being the case, the follow up question is then “Does any component prevent colour change?” I would ask the question directly if nitrogen in any form plays any part in the creation of the colour.

In terms of flavour, using the plant extracts will certainly qualify the products as flavoured bacon? How does the plant extracts not impart their flavour to the meat and how is the flavouring natural?

A Better Way

I am of the opinion that the use of plant extracts is warranted. I have an ongoing problem with current extraction processes and prefer the products to be used in the form in which it is found in nature. The discussion from the legislator with the company bears this preference up. Resent new equipment developments make this possible. Another key lesson to learn from the Spanish example is the importance of taking the consumer and industry along in the process. A man walking too far ahead of the people he is trying to lead is a man out for a walk and not a leader. He will achieve nothing! Bacon and ham and health – they all belong to all of us!

(c) eben van tonder

A list of my complete work on Nitrite


The list of questions I have on record relates to the extraction process and the flavour component of the brine. It is instructive for my own understanding of the rigour involved in such developments and I give it here in full from the references at my disposal.

Extraction process and Flavour

  1. What are the source materials used to make the product or any other used in the manufacture of your products)? More information is required than simply the statement that edible spice and fruit extracts are used.
  2. What kind of processes are being used e.g. physical, chemical or microbiological for the extracts? How many steps are there in the extraction process? Detail must be provided of the standardised product. How is variation prevented, etc.
  3. What components of the raw materials (used for the production of the brine product) are not extracted at each step of the production process i.e. fiber, fat-soluble aromatic components?
  4. Is the extraction process removing some of the flavouring components of the herbs, spices and fruits or are the flavouring components being concentrated? If, for example, no flavouring components are removed during the extraction process, they are concentrated during the drying process.
  5. What is the composition of the extracts/products you use in your meat products (bacon, sausages, etc.)? What are the constituents in the extracts? (e.g. antioxidants such as ascorbic acid at X level). Does the extraction process result in high levels of antioxidants and/or other chemical components? What is the functions of the commercial components
  6. What is the active component or components that are being used as a substitute for nitrite/nitrate preservatives to prevent the growth of harmful microorganisms and/or increase shelf-life? Can you describe how it kills or prevents the growth of microorganisms?
  7. If the product might have some technological effect, explain this in detail, including the effect on both the flavouring and the food. It is very important to understand the safety of the product.
  8. Please explain in detail if any other material added/used in the production of the meat product contribute to any technological function? If so, how? Are any materials used to stabilise the extract? If so, do they have an effect on the final food?
  9. How do you control microbial growth on the bacon and hams (please refer to your food safety management system documentation)?
  10. How is the preservation controlled, if the product does not have any preservative?
  11. What flavours (odour and/or taste) are being imparted to the meat or how is the flavour of the meat being modified by the flavourings? Would consumers identify your product as a flavoured bacon?
  12. Does any component impart a colour change in the pork meat?
  13. Does any component prevent colour change? Do you market your product as ‘flavoured bacon’ and are the natural flavouring an integral part of your product. What is the reason?