Answer:
Acidic fruit juice with lower pH
Explanation:
Sliced potatoes and apples are oxidized in direct contact of air. Thus, catecholase enzyme comes in contact with the cut or injured part of the fruit/ vegetable leading to its Oxidation.
Lemon juices contain antioxidants that can be used to coat potato/ apple slices. It slows the browning or oxidation of Apples or Potatoes. Lemon juice is acidic with lower pH value that helps in reducing the bacterial infection as well as the oxidation process less active.