The effect of high hydrostatic pressure on strawberry flavour compounds

The effects of high hydrostatic pressure on strawberry flavour compounds and the enzyme β-glucosidase were investigated. Strawberry (Fragaria × ananassa, cv. Elsanta) samples were submitted to high pressure ranging from 200 to 800 MPa. After the high pressure treatment, the samples were kept for 24 h at three different storage temperatures (4, 20 and 30°C) and, thereafter, the flavour was extracted by simultaneous steam distillation-solvent extraction using dichloromethane. Analysis was carried out by GC–MS and HPLC. The analytes of this study are three acids (namely butanoic acid, 2-methyl-butanoic acid and hexanoic acid), one ketone (2,4,6-heptatrione) and three furanones (5-hexyl-dihydro-3H-furan-2-one, 2,5-dimethyl-4-hydroxy-2H-furan-3-one and 2,5-dimethyl-4-hydroxy-2H-furan-3-one-glucoside). The highest flavour stability was observed when samples were treated with lower pressures and they were stored at 4 and 30° C. The enzyme β-glucosidase was found to be activated when pressures of 200 and 400 MPa were applied but inactivated considerably in the 600 and 800 MPa treatments.