The effects of high hydrostatic pressure on β-glucosidase, peroxidase and polyphenoloxidase in red raspberry (Rubus idaeus) and strawberry (Fragaria × ananassa)

The effects of high hydrostatic pressure on 3 important enzymes involved in flavour and colour bioformation, namely β-glucosidase, peroxidase and polyphenoloxidase, in red raspberry (Rubus idaeus) and strawberry (Fragaria × ananassa) were studied. Fruit samples were pressurised under 400, 600 and 800 MPa for 5, 10 and 15 min at a temperature controlled between 18 and 22 °C. After application of pressure, the enzymatic activities (A) were measured and compared to the initial activities of the samples (A0). The effect of high pressure is presented as a function of the ratio A/A0 over pressurising time. The inactivation of the enzymes is linked to the stability of anthocyanins in both fruits.