Decreased ascorbic acid levels and brown core development in pears (Pyrus communis L-cv. Conference)

Changes in ascorbic acid content are measured in the cortex tissue of Confe rence pears stored at various compositions of carbon, dioxide and oxygen, E nhanced carbon dioxide levels cause ascorbic acid concentrations to decline . Soon after ascorbic acid has declined below a certain value, browning of the core tissue can be observed. Reducing carbon dioxide levels before this value is reached causes ascorbic acid levels to increase again and prevent s browning to a great extent, In preliminary experiments with a photoacoust ic laser-based detection system, it was shown that pears that show browning produce ethane, which is most likely a result of membrane peroxidation, St orage conditions, ascorbic acid levels and browning in pears are discussed in relation to diffusion characteristics, energy-metabolism and energy main tenance levels of the fruit.