Membrane hydrophobicity was investigated for the osmotic distillation (OD) of tomato puree and membrane cleaning. Membrane hydrophobicity was measured by two methods : penetrating drop concentration (PDC%) for surface tension greater than 23 mN/m and penetration temperature (PT-degree-C) newly developed for membrane surface tension less than 23 mN/m. Cleaning methods for tomato paste fouled OD membranes were assessed. The membrane surface tension determined the cleaning regime. The most effective cleaner for membranes with a surface tension greater than 23 mN/m was 1% NaOH. The hydrophobic integrity of these membranes was destroyed during repeated fouling/cleaning trials. The most effective cleaner for membranes with a surface tension less than 23 mN/m was P3 Ultrasil 56. Water vapour flux was maintained and there was no salt leakage during repeated fouling/cleaning trials.