Regulation mechanism of magnetic field on pectinase and its preliminary application in postharvest sapodilla (Manilkara zapota)

•1. Conditions of magnetic field greatly inhibiting pectinase were found at 3 mT, 0.5 h.•2. Magnetic field altered the polarity of aromatic amino acid residues in pectinase.•3. The secondary structure of pectinase treated by magnetic field changed.•4. Magnetic field (3 mT, 0.5 h) also decreased activity of pectinase in sapodilla.•5. Delayed fruit softening by magnetic field was related with inhibited pectinase.