We present experimental measurements, obtained by a quasielastic neutron sc
attering experiment, of the self-diffusion coefficient of water confined in
the dense structure of lecithin-based gels. The inelastic neutron scatteri
ng (INS) technique was also used to monitor the dynamic state of water mole
cules involved in the gel structure. It is shown that, at least in highly c
oncentrated systems, the diffusional properties of water can be related wit
h the growth process of wormlike aggregates. However, an interpretation of
our data consistent with a number of experimental results in the literature
and with INS indications requires the adoption of a model in which the gel
structure is better described in terms of percolating aggregates rather th
an the usually described polymerlike entangled (not interconnected) network
. In such a way, we are pointing out the existence of an interpretative con
troversy calling for further investigation to be disentangled. The source o
f the inconsistencies is found in the commonly accepted basic assumption of
the existence of a simple scaling law, relating the average micellar lengt
h to the concentration. [S1063-651X(99)04312-3].