A Nottinghamshire company recalled a chocolate bar after a customer suffered an allergic reaction.
Trading Standards said traces of milk were found in The Skinny Food Co bar after it was alerted to the issue.
The Food Standards Agency (FSA) then issued a warning over the Skinny High Protein Low Sugar Duo Bars “because they contain milk which is not correctly declared on the label”.
A spokesperson for The Skinny Food Co, which is based in Arnold, said the bars were bought in and not manufactured by the company.
The salted caramel, chocolate brownie and cookies and cream bars were recalled.
Mark Walker, Group Manager for Trading Standards and Communities at Nottinghamshire County Council, told the authority’s Communities Committee meeting on July 19: “The service recently received a complaint about an allergic reaction to a chocolate bar that was being produced in Nottinghamshire.
“Formal samples were taken by Trading Standards officers to submit for testing and substantial quantities of milk were found.
“Officers then worked with the Food Standards Agency to assess the potential risk to consumers and agree the follow up actions.
“In this instance, a product recall was implemented and that puts a duty on the producer to do as much as they can to ensure the products supplied to other businesses or consumers is destroyed or returned to the manufacturer.
“At the moment we are monitoring the recall process [and] working with the business to make sure this doesn’t happen again. We’ll be looking at in the longer term what sort of action might come about by virtue of the fact that this product was on the market.”
A spokesperson for Skinny Food Co said: “The Skinny Food Co were notified by Nottinghamshire County Council that they had received a complaint about one of our bars. These bars are bought in by The Skinny Food Co and not manufactured at our site nor in Nottingham.
“The bars were found to have an elevated milk level which was higher than the allowed limit.”
Other tests and certifications before they were sold had suggested they could be sold as milk free, they said.
“However, once the issue was identified, The Skinny Food Co worked closely with the FSA to ensure that our customers were communicated to directly by us before the FSA notice was published.
“We have now sourced a new supplier so that our customers can continue to enjoy the product and the quality we, and they have become accustomed to.”