I have been trying to get a sense of the differences in surfactant content between the different dish soaps that I have been playing with in order for me to more effectively and efficiently try to come up with optimal bubble mixes for each. I am trying a number of approaches to the problem. One little experiment was just to see how much 'stuff' is in the detergents. So, I dehydrated approximately 20 grams each of Dawn Ultra (Classic Scent), Dawn Pro Pot & Pan and Non-concentrated Classic dawn.

The samples were poured onto aluminum foil squares (that had been pre-weighed) and put in a 230 degree Fahrenheit oven until the liquid was gone. What was left was a waxy substance coating the foil. The detergent-coated foil was then weighed.

The Dawn Ultra left behind 6.81 grams of stuff. Pot & Pan left behind 4.55 grams of stuff. Non-Concentrated Classic Dawn left behind 2.9 grams of stuff.

By percentage, the Dawn Ultra left behind 34% of its initial weight. Pot & Pan left behind 24% of its initial weight. NCCD left behind only 14% of its initial weight.

The big question is: does this represent the relative ratios of surfactant in each?

I assume that only a small percentage of what was left behind is actually surfactant, but I wonder if the amount of stuff left behind gives a clue as to the relative amount of surfactant.