Inhibition of core browning in ‘Yali’ pear fruit by post-harvest treatment with ascorbic acid

Summary‘Yali’ pear fruit (Pyrus bretschneideri Rehd.) were treated after harvest by vacuum infiltration (–50 kN m–2) at 25ºC with ascorbic acid (AsA) at concentrations of 0.1 mM, 1.0 mM, or 10.0 mM for 5 min, or with distilled water (control) under the same conditions. Thereafter, fruit were placed in air storage at 12ºC and cooled to 0ºC over 30 d, then held at 0ºC and 80 – 90% relative humidity (RH) for a further 150 d.The core browning index (CBI) was reduced by 10.4%, 24.5% or 40.0% in ‘Yali’ pears treated with 0.1, 1.0 or 10.0 mM AsA, respectively, after 180 d of storage. The firmness and total soluble solids (TSS) content of fruit treated with 10.0 mM AsA were also higher than those of control fruit. AsA treatment had an inhibitory effect on the accumulation of malondialdehyde and H2O2. Moreover, AsA treatment effectively delayed the decline in AsA and glutathione levels, and maintained the activities of superoxide dismutase, catalase and ascorbate peroxidase. These results suggest that the effects of AsA treatment on inhibiting core browning and improving post-harvest quality in ‘Yali’ pears might be due to reducing membrane lipid peroxidation by enhancing the capacity of cells to scavenge reactive oxygen species.