The applied frequency is inversely reciprocal to the characteristic lifetime of the network, that is, at long time this system can flow like a liquid. In contrast, the frequency sweep data of the 5% (w/w) lipid demonstrated a crossover of G0 and G00 which indicated that at low frequency the viscous part dominated and the sample behaved like a fluid. At the frequency larger than the crossover frequency (fc = 0.03 Hz), the system showed elastic behavior (G0 > G00). The fc can be used as a rough estimation of the characteristic network relaxation time (t = 1/2pfc) which is used to describe the tendency of the flow behaviors of materials (Tadros, 1996).