The trend to serve rare chicken livers is potentially exposing people to the risk of food poisoning, according to new research.
A study in the UK investigated the cooking times for chicken liver included in a number of popular current recipes.
It found many recommended serving them "pink" from cooking times, said to be insufficient to kill off Campylobacter, a common cause of food poisoning.
The research, jointly conducted by Manchester, Bangor and Liverpool universities, also found just over half (52%) of 141 chefs from a range of professional kitchens in the UK questioned wanted to serve chicken livers so rare they would not reach 70C, the temperature necessary to kill the pathogen.
Dr Paul Cross, of Bangor University's School of Environment, Natural Resources & Geography, said: "Chicken livers are served in many pubs and restaurants around the UK, and the trend seems to be for them to be served 'pink'.
"The research asked over a thousand members of the public and the chefs about their preferences, and whether they could identify safely cooked meats.
"The public were not able to identify safely cooked chicken livers by sight. Almost a third of the public participants identified livers as 'safe' which in fact had predicted Campylobacter survival rates of between 48% and 98%."
Professor Dan Rigby of The University of Manchester, who is one of the lead authors of the study, said: "As people are eating their steaks and other joints of red meat rarer, that trend seems to be extending to higher risk meats such as chicken livers and beef burgers.
"We found that many chefs were able to identify cooked livers that reached the temperature necessary to kill the pathogens but their preferences for the taste and texture of pink livers may be overriding their knowledge of food safety.
"In contrast the public were consistent in their choices - they tended to select dishes to eat that they thought met safe cooking guidelines. This is a concern, because the public were also poor at identifying by sight whether a cooked chicken liver had been cooked sufficiently to be safe."
The study highlighted that almost half the public sample (48%) agreed that cooking programmes on TV and recipes in magazines had influenced the public to serve meat pinker in the middle.
While 45% of the chefs questioned also agreed that they had noticed a trend of rarer and pinker chicken livers on TV, in recipes and among chefs.
Campylobacter is estimated to cause more than 100 deaths a year in the UK, and costs the economy about £900m, said the researchers.
About four in five cases of Campylobacter poisoning in the UK result from contaminated poultry, they added.
Prof Rigby concluded: "Given the high levels of contamination of UK chicken with Campylobacter, these survival rates suggest that the current trend for pink chicken liver recipes may be contributing to the public health burden of Campylobacter infection."