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Solid-state fermentation can be used to produce pectinases using agro-industrial byproducts. However, heat and mass transfer limitations make it difficult to control the temperature within the bioreactor, especially at large scale, so reliable scale-up strategies are essential. In the current work, we scaled up the production of pectinases in packed-bed bioreactors, from 12 g to 30 kg of dry substrate, the biggest scale yet reported for pectinase production. When compaction occurred, bed temperatures up to 47 °C were recorded and the pectinase activity in different regions of the bed at 26 h varied from 11 to 28 × 10 3 U kg −1 . When compaction was avoided, the maximum bed temperature was 32 °C and the pectinase activity at 26 h varied from 17 to 20 × 10 3 U kg −1 . The best result was obtained with a 40-cm high bed containing 27 kg of wheat bran and 3 kg of sugarcane bagasse, with switching of the temperature of the saturated inlet air between 24 °C and 32 °C. Under these conditions, the maximum productivity was 1840 U kg −1 h −1 at 10 h. We propose that the process can be scaled up to production scale by maintaining the same bed height and operational strategy, while increasing the width of the bed to several meters. If the superficial velocity of the air is maintained constant at 0.1 m s −1 , then the performance at scales involving several tonnes of solid substrate should be similar to that obtained in pilot-scale bioreactor in the current study. [ABSTRACT FROM AUTHOR]