Purity - Foam on top of ghb after shaking

[R3direct]

SWIM saw foam on top of ghb after shaking, slowly it disappears. He is thinking that this is a natural proces because all the bubbling-liquid comes to the top after agitation and those bubbles contain air which escapes. If it poses a problem in chemical processes one can use an emulgator says Wikipedia.

Is SWIM right or is it an indication of a possible impurity.

The ghb is not affected in itself in any kind and the production process is no kitchen chemistry.

[MrG]

Sounds like a detergent of some sorts would be responsible for that.

Is SWIY sure that he cleaned and rinsed his implements properly beforehand?

[R3direct]

Swim rinses also the HDPE bottle with soap and not only this bottle gives a foam after shaking but also a new bought glass bottle which was sterilized. So it must be the labware.

Does SWIY has knowledge of a detergent usable to solve the problem?