Mould is caused by foods that contain acids, like milk. This mould can build up in the sealing ring. To get rid of mould, remove the sealing ring from the lid and boil it.

Please note: the lid itself and the cup should not be boiled!

To prevent mould, clean the beaker regularly. We recommend cleaning the beaker after each use, either by hand or in the dishwasher.

Tip: store the cup open with the lid off.