How 'chicken juice' helps Campylobacter thrive

‘Chicken juice’ is the key to understanding the persistence of Campylobacter in food processing environments, a new study from the Institute of Food Research has shown.

Chicken juice, or organic matter that exudes from chicken carcasses, provides Campylobacter bacteria with the perfect environment in which to persist in the food chain. A high percentage of chickens reach consumers contaminated by the bacteria and, although cooking kills off the bacteria, around 50,000 people suffer from Campylobacter food poisoning in the UK each year.

Researchers Helen Brown, a PhD student, and Dr Arnoud van Vliet, her supervisor, collected the liquids produced from defrosting chickens and found that these liquids help Campylobacter attach to surfaces and subsequently form biofilms.

“We have discovered that this increase in biofilm formation was due to chicken juice coating the surfaces we used with a protein-rich film,” said Brown.

“This film then makes it much easier for the Campylobacter bacteria to attach to the surface, and it provides them with an additional rich food source.”

Brown and van Vliet set out to uncover the reason behind a number of paradoxes relating to Campylobacter.

While Campylobacter aren’t particularly hardy bacteria, they manage to survive well outside their natural habitat - the intestinal tract of poultry. They are sensitive to oxygen, but during biofilm formation, the bacteria protect themselves with a layer of slime. This also makes them more resistant to antimicrobials and disinfection treatments.

The researchers say that their new understanding of how Campylobacter operates will help reduce the number of contaminated chickens reaching consumers and, therefore, the number of Campylobacter food poisoning cases.

“This study highlights the importance of thorough cleaning of food preparation surfaces to limit the potential of bacteria to form biofilms,” said Brown.