A slice of apple left on a table slowly goes brown due to an enzymatic reaction. Dipping the apple slice in lemon juice prevents it from browning Which of the following best explains this result?
A. Lemon juice has enzymes which reverse the browning reaction
B. Lemon juice has a pH which inactivates the enzymes
C. Lemon juice functions to bleach the brown material
D. Lemon juice functions to dilute the brown material
Browning of the apple surface is due to the action of the enzyme polyphenol oxidase. Lemon juice is acidic and lowers the pH of the apple's surface. This inactivates the enzyme polyphenol oxidase, which works best at a neutral pH. This in turn reduces the browning action on the apple.
Therefore, the Correct Answer is B.
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