Enzymatic browning occurs when cut fruits and vegetables are exposed to which substance?ResponsesWaterWaterAirAirAcidAcidHeat

Identifying the Cause of Enzymatic Browning

1. Understanding Enzymatic Browning
   Enzymatic browning is a chemical process that occurs when certain fruits and vegetables are cut or damaged. This process is mainly caused by the exposure of the internal tissues to oxygen in the air.

2. Identifying the Substance
   Among the options provided — water, air, acid, and heat — the most relevant substance that triggers enzymatic browning is air. When fruits and vegetables are cut, the enzyme polyphenol oxidase (PPO) is exposed to oxygen present in the air, leading to the oxidation of phenolic compounds, resulting in a brown color.

3. Conclusion
   Although the other options may play minor roles in the overall browning process (e.g., heat can accelerate browning), the primary trigger for enzymatic browning is the exposure to air.

Final Answer

Air is the substance that causes enzymatic browning when cut fruits and vegetables are exposed to it.