Browning Inhibition and Textural Changes of Pre-Peeled Potatoes Caused by Anaerobic Conditions

Sulphite treatment is often used for inhibition of enzymatic browning of pre-peeled potatoes. Introduction of CO₂ or N₂ gases in the immersion water was investigated as an alternative to sulphite. The samples were stored at 4 °C. Daily introduction of the gases reduced the O₂ content from approx. 8.8 mg/L (measured at 20 °C) to 0.2-1.9 mg/L during the immersion period. The CO₂ treatment inhibited the browning completely and N₂ treatment did not. It is assumed that this is due to the lower pH in the CO₂ water. When CO₂ was added only one time at the start of the experiment, it also inhibited discoloration, but the immersion water developed a weak brown colour. Both the CO₂ and the N₂ treatment induced hardening in the outer potato tuber tissue after cooking after 4-7 d of storage, as did Na₂SO₃ solutions.