Honestly, we feel the same way as most consumers and we often have the feeling that shampoo, soap, toothpaste and even washing-up liquid clean most effectively when there is a lot of foam. An exciting association, but is there something to it?
The power of imagination
First of all, we are in the best of company, because pretty much everyone thinks that a lot of foam means that a lot of cleaning is done well. It's exciting because we don't actually have any evidence of this in everyday life. It's actually more of a feeling. Maybe it's because we can distribute foam well and the cleaning is more or less visible to us. On the other hand, the experience with detergents of any kind is different if they foam less. A little cannot be distributed well and so we have the impression that we could not clean thoroughly. It seems that for us, the amount of foam is the equivalent of cleaning performance.
And the reality?
Well, the fact is that we cannot see the actual cleaning substances, the surfactants. How much of them is in a product only has something to do with the amount of foam. There are detergents that hardly foam at all and still do their job fantastically. What is important for cleaning is how well we distribute the surfactants on the surface to be cleaned. Foam can actually be a hindrance: if a product produces a lot of foam, we spread it without scrubbing thoroughly enough or letting the surfactants work in long enough for the dirt to bind. The foam itself can, but does not necessarily have to, contain a lot of surfactants and in any case we have to treat the corresponding surface well with the cleaning agent and let it work for a reasonable time. Even with foam products such. This applies, for example, to facial cleansing foam, which has been popular for some time: just spreading and rinsing off quickly is not enough.
We shouldn't be fooled by the amount of foam, although of course foam is always beautiful and may feel good. Surfactants are responsible for the cleaning performance and we must always apply and distribute each product thoroughly and only rinse off after a reasonable time.
Note to self: lots of suds doesn't mean great cleaning.