Question

What kind of chemical change do you think occurs when a banana peel turns brown in the open air?

Answer 1

Enzyme catalysed oxidation and then polymerisation the resulting product.......

Explanation:

Bananas contain the enzyme polyphenol oxidase. One of the actions of this enzyme is to promote oxidation of the amino acid tyrosine (naturally occurring in the banana) into o-quinone. The enzyme then causes rapid polymerisation of the single ringed o-quinone into one of the polycylic compounds known as melanins. These are dark coloured compounds, which is why the peel turns brown.