A different view on a nice piece of meat

Some meat products like steak, veal escalope or duck breast are delicious to eat ‘medium-rare’ or sometimes even raw. But how safe is that? Insufficient heating can lead to contamination with, for example, Escherichia coli or Listeria monocytogenes.

The danger of food being contaminated with these bacteria is that in some cases it can lead to serious diseases for consumer. For this reason the NVWA strictly checks for the presence of the bacteria on these products and labels these products as foods with a high risk profile or ready-to-eat foods more often. Not nice, because in the event of contamination, the products will be blocked or removed from the market.

Escherichia coli (E. coli)

Escherichia coli

Escherichia coli (E. coli) is a bacteria that occurs naturally in the intestines of humans and animals. Most of E-coli species are harmless, but the Shiga toxin-producing E.coli bacteria (STEC) causes damage to the the cells in the intestinal wall (verocytes). The classic term for STEC is therefore verocytotoxigenic E.coli (VTEC). A rare subgroup within STEC is the enterohemorrhagic E. coli (EHEC). Contamination with this bacteria can lead to a serious intestinal infection where the toxin can enter the bloodstream with possible kidney damage as a result. The most severe form of this is the Hemolytic Uremic Syndrome (HUS), which can sometimes be fatal.

Listeria monocytogenes

Listeria monocytogenes is a bacteria that can be present in the normal intestinal flora of humans and animals and lives both on the ground and in surface water. The bacteria can occur in certain foods, like unpasteurized milk, soft cheeses made from raw milk and dried or cold smoked fish. Consumption of food contaminated by the named bacteria can cause the infectious disease Listeriosis. This infectious disease is usually mild in healthy people, but can have more serious consequences in young children, the elderly and people with weakened immune systems. In this group meningitis or blood poisoning can occur, sometimes even followed by a fatal outcome. In pregnant women there is a risk of death of the unborn child, premature birth or serious illness of the newborn child.

Listeria monocytogenes

How does meat get contaminated?

The contamination of meat with harmful bacteria can occur during the slaughter process. When intestinal contents end up on the carcass, the meat can be contaminated. But the skin can also be a source of infection. During the cutting, the bacteria can spread over the meat. The meat will then be contaminated on the outside.

Precautionary actions

Good hygiene throughout the production chain, from slaughter to fork, is of great importance to prevent contamination. A correct procedure during slaughter can prevent contamination of the carcass. Sterilization of materials and personal hygiene are both important, but a clean working invironment also helps. In addition to a good overall structural condition of the production location, the following must be considered: the use of clean suspension systems, proper cleaning of the evaporators and the ventilation system, good condensation and moisture control and sufficient slope in the floors towards pits and gutters, so that no puddles of water remain so that this is not a source of bacteria.

In the cutting plant the faecal contamination on the carcasses must be cut away and not sprayed off. Spraying off contamination is out of the question because the bacteria will then be spread throughout the room. The use of seperate cutting tables, cutting boards and knives for the carcasses ensures that the contamination remains there. For further processing of meat parts, use a clean working environment seperated from the carcasses to prevent cross-contamination. Use sterile knives and cutting boards and make sure that other materials and working environments are cleaned regularly and thoroughly.

Thereafter, a good and quick cooling is necessary to inhibit the growth of any bacteria left behind. The temperature of the meat should in any case stay remain below 7°C.

Control measures recorded in the HACCP analysis

The risk of STEC or L. monocytogenes must be included in the HACCP analysis so that the correct control measures can be adjusted accordingly. Such as good knowledge among employees about hygienic working or clear hygiene agreements with suppliers. Hygiene inspections are necessary to verify whether the measures taken are properly observed and sufficiently effective. Should EHEC or L. monocytogenes still be found, appropriate actions should be taken to minimize the damage as much as possible.

Correct instructions for use on the packaging

A food infection by STEC or Listeria monocytogenes is prevented by heating products sufficiently before consumption. From 65°C a large reduction in the number of STEC bacteria is achieved within a few seconds. Listeria monocytogenes is also sensitive to temperature and is quickly killed above 70°C.
Correct instructions for use on the packaging of the product is very important. Any possible contamination is on the outside of the product. Therefore it is important to mention that not only the bottom and top sides are heated well and for a sufficient time, but that the sides are also completely seared. Look for the right combination of temperature and time, over high heat or medium heat and validate the cooking method in practice with different types of pans and heat sources. After all, the consumer expects the product to remain a beautiful rose color on the inside.

NVWA checks

The NVWA stricly monitors compliance with legislation and the presence of E. coli in food. The NVWA applies an intervention policy when STEC is present in food. In this it makes a distinction between low and high-risk profile foods.
Low-risk profile foods are foods that can reasonably be expected to be consumed after adequate heating or other processing has been performed to eliminate or reduce STEC to acceptable levels. Intervention for these foods (blocking the relevant batch of foods or taking them off the market) will only take place if the very dangerous variant of EHEC is present in the food, which means that it can be harmful to health according to Regulation (EC) 178/2002.
High-risk profile foods are ready-to-eat products that are not heated before consumption. When STEC is found in these products, the batch of foods is banned from the market or withdrawn and a fine report is drawn up.
With regard to L. Monocytogenes, the producer initially determines whether a product is a ready-to-eat food. Thereafter, the NVWA tests the effectiveness of the preparation advice based on the following: is the heating instruction on the packaging sufficient to eliminate any L. monocytogenes or to reduce it to an acceptable level? In doing so, the NVBA will assume the use of the product that can reasonably be expected.

Prevent contamination!

As a producer, you naturally ensure that both the quality and safety of your product are guaranteed. You can prevent a contamination with E.coli or Listeria, for example, by taking good preventive measures and carrying out process validations. This way you can be sure that your product is safe!

References

https://www.rivm.nl/e-coli-escherichia-coli/stec-ehec

https://www.euro.who.int/en/health-topics/disease-prevention/food-safety/outbreaks-of-e.-coli-o104h4-infection

https://www.nvwa.nl/onderwerpen/e-coli-bacterien-stec-ehec/documenten/consument/eten-drinken-roken/bacterien/e.-coli/beleidslijn-interventie-aanwezigheid-stec-in-levensmiddelen

Commission Regulation (EC) No. 2073/2005 of the Comission of 15 November 2005 on microbiological criteria for foodstuffs

Regulation (EC) No. 178/2002 of the European Parliament and of the Council of 28 January 2002, laying down the general principles and requirements of food law, establishing a European Food Safety Authority and laying down procedures in food safety matters