In an email that I received this morning, there was a question of using gelling agents (alginate, carraghens, etc.) in Molecular Gastronomy.
Indeed this question is based on a confusion between science and technology, between molecular gastronomy( science) and molecular cuisine (cooking).
Perhaps you will be interested to read the chapter that I produced for the Formulation Day 2009 (production soon). Indeed, you will see that gelling agents are not discussed... because if you think about gels in general, it's more general (hence powerful technologically) than thinking about some gels in particular. Of course, then the gels have to be made, but this is no longer a scientific question, rather a technological one.
Where could alginates and oter be used? In any colloidal system described by a CDS/NPOS formula where a gel (/S) structure is included.