Listeria monocytogenes

Welcome again to our blog as we say goodbye to summer! In today’s Blog, we will discuss one of the hottest issues in food industry at present-ensuring food safety against Listeria.

At Amerex, we are always on the lookout for important issues that concern major sectors of the food industry. Particularly, in recent months, various health problems caused by Listeria monocytogenes have surged, so let’s look into this in detail to find out more. For example, heat is not a deterrent to the growth of this bacteria, many products that are manufactured using various heat treatments, like fermented sausage (“chorizo”), cooked blood sausage (“morcilla”), roasted meat (“carne mechada”), or any other product strongly treated by heat, might still be affected by the growth of Listeria. There is a common tendency to rely these heat treatments followed by the refrigeration processes to eliminate the presence of these bacteria entirely but, ultimately, these act only as barriers. We believe that each barrier, though beneficial, works as an additional wall to prevent contamination. Therefore, the more barriers, the better the safety.

List of protective barriers: moisture and pH, packaging, chemical additives, atmosphere control. storage, HACCP systems and heat treatment

The need to protect meat products like the ones mentioned before against the harmful effects of Listeria is a serious issue that the food industry deals with currently. In case of the meat, there are two barriers: the heat treatment, which is the former barrier, followed by the refrigerated storage, which acts as the latter. Specifically related to the storage, we would like to cite this article from El Mundo: Listeria: Crece la amenaza de la bacteria que sobrevive en tu nevera (“Listeria: The threat of the bacteria that survives in your fridge grows”). This article describes the occurrence, development and consequences of the presence of Listeria monocytogenes in food and the measures to be taken for preventing its appearance and growth. However, heat treatment and refrigeration, combined with control of the product’s initial microbial load and hygiene, are sometimes taken into consideration while at other times, overlooked.

As companies in the meat sector, you may think that by controlling the above-mentioned barriers, you have already controlled the presence of Listeria, but sometimes, things are not that simple. In addition to all possible barriers, out of which heat treatment, refrigeration and hygiene are the most significant to consider when it comes to safety control, there exist further barriers like the preservative solutions provided by Amerex. One of our top sales, Fermitrat® Export, would act as an additional barrier by itself.

Image showing the effect of Fermitrat-Export, one of our preservatives, against Listeria sp. inoculated in foie. You can see how both dosages of Fermitrat control growth better, practically eliminating this bacteria at a dosage of 1.5 g/Kg of the preservative
Image showing the effect of Fermitrat-Export, one of our preservatives, against three strains of Listeria sp. inoculated into sliced ​​turkey. At a dosage of 1.5 g/Kg of Fermitrat, a bacteriostatic effect is produced, preventing the growth of the bacteria which is three logarithmic units lower than the sample without the preservative

Among the barriers, we can find references in the legislation about microbiological criteria, which includes pH and aW criteria. Therefore, once these two parameters are met, there is no further requirement to ensure safety.

Extract from the legislation about microbiological criteria, which establishes that products with less or equal to 4.4 pH levels and less or equal to 0.92 water activity, or products with with less or equal to 5 pH levels and less or equal to 0.94 water activity, cannot support the growth of Listeria monocytogenes

You may think that by abiding to the legislative parameters and maintaining adequate supervision pf certain other parameters, you are free from danger against Listeria. However, if you aim to create higher quality, more desirable products, you could even lower the pH and aW requirements by adding a protector in your manufacturing process.

The choice is in your hands, we are available round the clock to clarify your doubts and uncertainties and to provide you the necessary assistance to meet your requirements.

Phone number: +34 91 845 42 14

Amerex see you neXt time
Our Products

Contact us

6 + 1 = ?