The fungal pellets were formed from the surface thermodynamic balance between fungal cell and liquid media. The Gibbs free energy of pellet formation of the initial culture media (-73 similar to -81 ergs/cm(2)) were increased to -13 similar to 46 ergs/cm(2) at 48 h, FTIR analysis showed that factors inducing pellet formation simultaneously increased the cell wall hydrophobicity of Aspergillus niger.