Most severe internal browning was observed on CO2 adsorbent-untreated pears under high CO2 levels (7-9 %) increasing since the beginning of storage. Therefore, there were no significant differences on the color and flesh firmness among the treatments, except controls, during cold-storage. Internal browning-affected pears showed harder flesh, greener and darker color compared with unaffected pears. Interestingly, control samples also suffered internal browning under low CO2 ( ̴ 0.1 %) and high O2 ( ̴ 20.5 %) concentrations after 5 months in storage with medium damage levels