Although organic and ‘natural’ are perceived to be the safer option this is not always the case when it comes to preserving finished meat products.
Although there are natural preservatives on the market, do we know if they work in all products against all organisms, and to what degree? There seems to be far more research concerning ‘chemical’ preservatives but retailers like clean labels, and if not clean, they like the term ‘natural’. Consumer trends drive the market, so the race to develop effective ‘natural’ preservatives is on.
In order to discuss preservatives we must first understand bacteria (otherwise known as pathogens). Bacteria epitomise the notion of ‘small but powerful’ when we consider that they can compost an entire elephant, fertilise a tree and even lighten up the oceans in an eerie glow.
Recent research has shown that bacteria signal to each other in order to band together in a phenomenon called ‘quorum sensing’. This phenomenon, microbiologists have discovered, indicates that bacteria don’t just eat, increase in size and multiply – they also communicate. Using molecules they can collectively decide how best to behave in certain surroundings.
Organic acids play an important role in controlling pathogens for both live animals and eventually in processed beef, pork, poultry and fish products. Fortunately these acids contain the word ‘organic’ and so perhaps fly under the radar of the ‘natural’ lobby.
It is increasingly shown that the gut health of living animals is important in preventing intestinal pathogens. This can be primarily achieved through the controlled acidification of feed which we now know protects both the feed and the animal from pathogens. Acids available include products such as Pro GIT SF2, a combination of formic, lactic and citric acids put into calcium salts. Because these acids are bound to calcium (at a lower acid binding capacity than limestone) it leads to improved animal performance and notably less diarrhoea in poultry.
Although not strictly ‘natural’, the recent introduction of new co-spray dried acetates provides a very high degree of food safety. Sodium chloride, although manufactured in natural surroundings, is a molecule with two substances considered detrimental to health: sodium and chlorine. It seems however this is tolerated by consumers as bland food is too high a cost to pay for health.
The acetate formulation mentioned above is a 50/50 composition of sodium lactate and sodium acetate. Although both components of this product contain sodium, this preservative allows for a decrease in total salt, without a loss in taste. Proven effective against listeria, it is increasingly used by large meat processors. Additional benefits include the fact that products can now have a cleaner label and at a lower cost with no effect on sensory parameters, such as taste, odour and mouth feel.
So, although the lobby for ‘natural’ and ‘organic’ grows, both sides of the argument must be examined before we bend to the whimsical dictates of the market. The customer may, in this instance, be wrong.
Bacteria of concern
• The fatality rate when infected by listeria monocytogenes is 25 per cent; Salmonella is less than one per cent. Pasteurisation and sufficient cooking do kill listeria; but contamination may occur after cooking and before packaging. Producers of ready-to-eat foods, such as hot dogs and deli meats, must follow extensive sanitation policies and procedures to prevent listeria contamination.
• Clostridium botulinim is a neurotoxin, which, as the name suggests – causes botulism, with a mortality rate as high as 10 per cent. Commercial heat pasteurisation, vacuum packed pasteurisation, and hot smoking products may not be sufficient enough to kill all spores and therefore safety of these products must be based on preventing growth and toxin production.
