Two elderly patients with other serious illness died.
The pathogen was not detected in the product but a link was made through epidemiological evidence.
COOP Forloren Hare 350g was sold in Coop supermarkets under the brand Normeat A/S and produced by Tulip.
However, Tulip said the product cannot leave the factory containing Salmonella due to the heating process.
Insufficient product heating
Danish agencies believe insufficient heating of the meal caused the outbreak and advised cooking at above 75 degrees for at least one minute.
It was produced on 4 November last year and is sold frozen to be heated in the oven or microwave.
Fødevarestyrelsen (The Danish Veterinary and Food Administration) told FoodQualityNews that the national outbreak group identified a specific product and production date under suspicion.
The type of Salmonella is typically found in pigs so the investigation looked at fresh meat, meat products and frozen meals.
“The trace back and recall is based solely on epidemiological evidence. Salmonella has not been detected in samples from the frozen meal. We suspect the contamination to be low and unevenly distributed within the recalled batch,” said the DVFA.
“Interviews were possible with 15 patients, however two were considered to be secondary cases. Ten cases of the remaining 13 patients recalled eating frozen meat loaf from a specific supermarket chain.”
Production processes prevent Salmonella
Michael Ravn, spokesman for Tulip, told us it believes the product is not the source of the outbreak.
“It is heated in the production process and any Salmonella would be killed. We are annoyed with this connection, it isn’t possible. The degrees Celsius Salmonella is killed at is 70 and the product components are heated way beyond 70 degrees and from heating it is directly frozen,” he said.
“We withdrew it as the suspicion was raised and food safety is the most important thing for us. We have collected a lot of samples from the same production date and tested them in an independent lab and all tests are negative.”
Ravn said it is of the conviction that the product is not to blame.
“We have heard since November that four people ate the product. Four out of 18 is weak evidence,” he said.
“The way it is produced and everything in the production facility was examined with no deviations found. We are hoping the real source is found as it is a bad outbreak.
“We will continue making it and we are always discussing such factors [changing labelling] but the package says how the product should be heated in the microwave or oven.”
Fødevarestyrelsen said it does not have any reason to question the safety of the business’ products from other production dates.
“No hygienic breaches or faults have been found at the production facility, and we know the food business as a very responsible operator with a high focus on food safety.
“Until the Central Outbreak Management Group can conclude the outbreak over we cannot make final conclusions on the source.”
This group consists of the Statens Serum Institut (SSI), the National Food Institute, Technical University of Denmark and DVFA.
“We have no data on how the patients got the Salmonella transferred from the frozen meal in question. The most probable explanation is insufficient heating of the product,” saidFødevarestyrelsen.
“The time needed to kill Salmonella depends on many things as where the pathogen is situated i.e. if it is on the surface or in the middle of the product, on the number of bacteria present etc.”
Statens Serum Institut told us that dates of illness onset were from December 2016 to February.
The serotype is Salmonella O:4,5,12; H:i:- (also called monophasic Salmonella Typhimurium) which is very common in Denmark.
Based on whole genome sequencing the same Salmonella subtype was found in all patients.
Initial reports said 19 people were ill but one case was excluded after further typing.
There were no food leftovers from patients to analyse and testing of other similar products did not reveal Salmonella.
It is possible consumers may have product from the affected lot (date 1-8-17 and code 7340011419334) in the freezer. They are urged to discard it or return it to the store.