The CT1 mutant is a hyperproducer of pectinases isolated from Penicillium occitanis. It highly secretes pectinases on citrus pectin as well as on orange peel. Production in fermentor was carried out on another local by-product of wheat manufactories, the gruel. This substrate, poor in pectic substances, showed the highest capacity to induce pectinases, strengthening the fact that our mutant is a constitutive one. Yield and productivity are much higher on gruel in comparison with citrus pectin and orange peel. The extracellular juice of CT1 gruel fermentation was then applied in the process of olive oil extraction. An improvement of 10% on the oil yield was obtained at an industrial scale. (c) 2006 Elsevier Inc. All rights reserved.