Cell wall-modifying enzymes and firmness loss in ripening Golden Reinders apples: A comparison between calcium dips and ULO storage
Abel Ortiz, Jordi Graell and Isabel Lara
Food Chemistry, Volume 128, Issue 4, 15 October 2011, Pages 1072–1079
2011
บทคัดย่อ
Calcium treatment and storage under ultra-low oxygen (ULO) conditions are common post-harvest practices aimed at delaying ripening-related softening of apple (Malus × domestica Borkh.) fruit, but the biochemical mechanisms underlying these effects have not been determined conclusively to date. In this study, commercially mature ‘Golden Reinders’ apples were dipped in 2% calcium chloride prior to storage at 1 °C and 92% RH under either regular air or ultra-low oxygen (ULO; 1kPa O2:2kPa CO2) for 19 or 31 weeks, and kept thereafter at 20 °C for 0, 7 or 14 days in order to simulate the usual marketing time. Cell wall composition and cell wall-modifying enzyme activities were determined in relation to fruit firmness. ULO-storage and calcium dips were effective for firmness preservation, seemingly due to decreased pectin solubilisation. β-Galactosidase, α-l-arabinofuranosidase and pectate lyase activities were correlated positively with firmness loss of ‘Golden Reinders’ fruit after storage