Andy,
Thinking about my previous post....

Cheap cooking oil produced a LOT of foam when being modified.

Olive oil produces only a slight amount of foam.

The washing up liquid is supposed to act as a catalyst for the glycerine.

If there is far less foam being produced then that would indicate that there is a far greater take up of glycerine by the olive oil and the washing up liquid is being utilised more and thus producing less foam ........ ???

It would be nice if Stewart and the bio-chemist he has contact with could express some thoughts on that.......

Reg