Plants, algae, and their derivatives paper, textiles, etc. are complex systems that are chiefly composed of a web of cellulose fibers. The arrangement of solvents within the polymeric structure is of great importance since cellulose degradation is strongly influenced by water accessibility. Here we show a model based on small angle neutron scattering (SANS) data able to deconvolve the scattering contributions of both polymeric structures and solvent clusters trapped along the polymeric fibers. The relevance of our model resides in the exploitation of a large number of biopolymer networks that are known to share structures similar to that of cellulose.