The surface of the plastic is VERY smooth, so it has excellent non-stick properties from the ground up. In order to maintain this, do not work with/clean the dehydrator trays with abrasive products or objects. They should also not be put in the dishwasher, as the salt attacks smooth surfaces. The shelves have no gaps or holes - they can be filled with a little washing-up water and soaked stacked on top of each other; this way they are effortlessly clean after a short time.
If you are processing strongly coloured food (beetroot, tomatoes, carrots) and want to avoid discolouration of the dehydrator trays, it is advisable to cut baking paper to size. Discolouration caused by carrots, for example, is harmless and can usually be removed with a little oil and/or baking powder.