Abstract Water soluble pectin was isolated from strawberries. Sugar composition, degree of esterification and molar mass were compared with commercial apple pectin. Both pectins were subjected to enzymatic de-esterification by recombinant Aspergillus aculeatus pectinmethylesterase (PME). Rate of enzymatic de-esterification at elevated pressures (0.1–500 MPa) and temperatures (20–60 °C) was assayed by measuring the release of methanol as a function of time. Optimal activity was observed at 200–300 MPa combined with 45–55 °C. At all conditions investigated, both pectins were de-esterified at similar initial rates. However, after prolonged enzymatic treatment at atmospheric pressure and 30 °C, apple pectin was de-esterified to a significantly lower degree of esterification (7%) than strawberry pectin (32%). The mode of action of A. aculeatus PME was investigated by enzymatic fingerprinting of de-esterified pectin chains. The enzyme de-esterified according to a “multiple chain, multiple attack” mechanism, irrespective of the substrate. Industrial relevance This article demonstrates that both strawberry and apple pectin de-esterification by recombinant Aspergillus aculeatus PME is accelerated by high hydrostatic pressure. Since de-esterification of pectin in fruits gives rise to a texture improvement, this enzyme can be used to minimize texture damage during high-pressure processing of fruits and fruit-based products. It was also shown that this enzyme de-esterifies strawberry and apple pectin according to a “multiple chain, multiple attack” mechanism. The resulting pattern of esterification might have an influence on textural properties of fruits.