Herein is the first report of solvent induced anisotropy in 12-hydroxystearic acid self-assembled fibrillar networks. Increasing the chain length of polar solvent, such as nitrites and ketones, tailored the anisotropy of the fibrillar aggregates. 12HSA molecular gels, comprised of alkanes, exhibited an isotropic fibrillar network irrespective of the alkane chain length. In polar solvents, anisotropy, observed using 2D powder x-ray diffraction profiles, is correlated to a fibrillar supramolecular morphologies in long chain nitrites and ketones while sphereulitic crystals are correlated to x-ray diffraction patterns with an isotropic scatter intensity in short chain ketones and nitrites. These changes directly modify the final physical properties of the gels. (C) 2017 Elsevier B.V. All rights reserved.