Lipases (triacylglycerol hydrolases, EC 3.1.1.3) are a class of enzymes with high industrial importance. An option for the production of this enzyme is through fungal growth via solid-state fermentation (SSF). Thus, this research presents a study of lipase production by Penicillium roqueforti ATCC 10110 through SSF using cocoa bran residues (Theobroma cacao) as a substrate. To achieve maximum lipase production, fermentation time (0 to 120 h) and palm oil (PO) percentage (0 to 50%) were optimized through analysis of one factor at a time (OFAT), with lipase activity as the response. The amount of cocoa was fixed (5 g), the incubation temperature was maintained at 27 °C, and the moisture content was established at 70%. For a 72 h incubation, the highest enzyme activity achieved using SSF without adding PO was 14.67 ± 1.47 U g⁻¹, whereas with PO (30%), it was 33.33 ± 3.33 U g⁻¹, thus demonstrating a 44% increase in enzyme activity. Through the OFAT methodology, it was possible to confirm that supplementation with palm residue was efficient and maximized the lipase of P. roqueforti ATCC 10110.

Solid state fermentation (SSF) simulates the natural conditions fungal growth, where the amount of water in the reaction medium must be restricted, thus limiting the use of liquid substrate. An analytical strategy to deal with this limitation is the design of blending with constraints. Thus, the objective of the work was to optimize two constrained waste mixtures for the production of lipase by Penicillium roqueforti ATCC 10110 under SSF, using different substrates that combine solid and liquid waste. For this, the best fermentation time was determined through a fermentative profile, afterwards a restricted-mix design with lower and upper limits of the components of mixture I (cocoa residue, solid palm oil residue and liquid palm oil residue) and II (cocoa residue, mango residue and palm oil residue liquid palm) was applied. By means of Pareto and contour graphs, the maximum production points of lipase in mixtures I (6.67 ± 0.34 U g⁻¹) and II (6.87 ± 0.35 U g⁻¹) were obtained. The restricted mixture design proved to be a promising tool in the production of lipase by P. roqueforti ATCC 10110 under SSF since the use of restrictions is useful when intending to combine solid and liquid residues in fermentation processes.