Several Danish websites, including online supermarket Nemlig.com, have shown readers how to dip a balloon in melted chocolate, wait for the chocolate to solidify, and then pop the balloon, to create attractive chocolate bowls.
However, Maja Kirkegaard from the DVFA told Danish news agency Ritzau that balloons were not designed for food contact, rendering the method potentially unhealthy.
“Although the impact of the various substances is small in a single chocolate bowl, it is essential to minimise one's overall exposure to harmful substances, particularly the carcinogens and endocrine disruptors,” she told Danish news agency Ritzau.
“Balloons are made of rubber, and the production of rubber can form nitrosamines and nitrosatable substances,” she explained. “There may also be other unknown chemical substances that are not intended for contact with food.”
A spot check by Denmark's Environmental Protection Agency in 2014 found illegal substances in 23 of the 39 balloons checked.
Danish news agency Ritzau advised readers to instead freeze a water in a bowl of the desired shape and then to pour melted chocolate over the frozen mold.
If a balloon is used, Ritzau recommended wrapping it in clingfilm before applying the chocolate, thus minimising the transfer of unhealthy nitrosamines. However, in that case the temperature of the chocolate must not exceed 34C.
Below is a video made by Mette Holmgren, demonstrating her now discredited method of making chocolate bowls.