Question

Why cut apple turns a brown colour?

Answer 1

• Apples contains an enzyme called polyphenol oxidase (PPO) also known as tyrosinase. 
• Cutting an apple exposes its cells to the atmospheric oxygen and oxidizes the phenolic compounds present in apples. This is called the “enzymatic browning” that turns a cut apple brown.
• In addition to apples, enzymatic browning is also evident in bananas, pears, avocados and even potatoes.