A type of lectin in red kidney beans was behind an outbreak in Denmark earlier this year.

Poisoning left 45 people sick, including 24 on one day, in late April. It was limited to a catering company that delivered food for another business in the Copenhagen area.

The outbreak was caused by phytohaemagglutinin (PHA) in frozen red kidney beans from Turkey, via Sweden.

Such poisoning becoming more common
Nikolas Kühn Hove, head of crises management at the Danish Veterinary and Food Administration (Fødevarestyrelsen), said it appeared the kidney beans weren’t boiled for long enough.

“We have one day where people got sick quite quickly because the source of the outbreak, we believe, is red kidney beans that weren’t boiled for long enough to reduce the toxins. We got reports about people getting ill, we visited the place and saw their menu plan. We saw that there were salads with kidney beans,” he told Food Safety News.

“We dug into the product and it was labeled as pre-cooked kidney beans, we took samples of the kidney bean salad and based on symptoms the patients had, it looked like it was some kind of poisoning. We directed our investigations to what kind of meals they had that week and we did interviews with all patients asking them what they had eaten on what dates and in that investigation the kidney bean salad was significant.”

Symptoms of poisoning include vomiting and diarrhea within a few hours of eating beans that have not been cooked for long enough to reduce this lectin and last for a few hours. Only a few beans are needed to cause poisoning.

Kuhn Hove said Denmark has had such incidents three or four times during the past year to 18 months.

“Compared to a normal outbreak it is big as it is a lunch catering service. We see these lunch catering service outbreaks from time to time and we can see in our statistics that because catering companies providing lunch are getting bigger the outbreaks they make also get bigger but they are normally point source, a single day where something has gone wrong,” he said.

“We also see that due to the rise in vegan and plant-based meat substitutes, like if you make a lasagne without meat you would normally add beans to it, in these situations catering companies tend to buy pre-cooked beans.”

Translation troubles
In the April outbreak, the producer of beans is thought to have used blanching for 10 to 15 minutes but they need 30 or 45 minutes of cooking at least, according to officials.

Kuhn Hove said because the beans were produced in another country the labeling was translated a few times.

“In this case, it looks as if blanched has been lost in translation into pre-cooked and the catering company bought a product that was not what they expected. The most difficult part was tracking down whether these beans were pre-cooked or not. Who was responsible for the correct labeling of the product and how can we ensure that was corrected,” he said.

“It was difficult to figure out how to put the right measures in place to avoid the same case happening again because the product was moved through several countries. The producer has made a final product that is legal and safe but it has to be handled correctly all the way through the chain.”

Problems due to translation is one of a number of things the authority has a focus on, said Kuhn Hove.

“With the increased focus and demand on end products this is an issue other authorities and companies should be aware of to make sure products are safe. In the food sector, we have had the trend of eating meat cooked in an oven where the temperature is not hot enough to kill bacteria. We also have products used in a new way or by people who are not used to dealing with such products and it takes new or additional focus to ensure it is produced in a safe manner.”

Campylobacter outbreak over
Meanwhile, the investigation into a Campylobacter jejuni outbreak linked to a dairy in Bornholm has closed.

Patient interviews pointed toward pasteurized milk from Bornholms Andelsmejeri (Bornholm Dairy) as the source of infection but product testing was negative for Campylobacter.

Around 154 people were sick from late May to early June and at least 16 people needed hospital treatment. Patients ranged in age from 9 months to 97 years old.

Kuhn Hove said the dairy was in production at all times but it has enhanced a surveillance program and authorities are doing additional spot checks at the facility to ensure products are safe.

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