Oxidative rancidity is a major cause of food spoilage, particularly in products containing fats and oils. This process is often catalyzed by the presence of metal ions (like iron and copper). Sequestering agents are used to counteract this effect.
Step 1: Understanding the Question:
The question asks to identify an additive that acts as a sequestering agent, which means it binds to metal ions to prevent them from accelerating oxidation.
Step 2: Detailed Explanation:
A sequestering agent, or chelating agent, forms stable complexes with metal ions, effectively removing them from the reaction system. Let's examine the options:
(A) Sodium benzoate: This is primarily an antimicrobial agent, effective against yeasts and molds in acidic foods.
(B) EDTA (Ethylenediaminetetraacetic acid): This is a powerful and widely used chelating agent. Its molecular structure allows it to wrap around and bind tightly to metal ions, making them chemically inert and unable to catalyze oxidative reactions.
(C) Citric acid: While citric acid does have some mild chelating properties, its primary role in food is as an acidulant (to provide tartness) and a pH control agent. EDTA is significantly more effective as a sequesterant.
(D) Sodium chloride: This is common salt, used for flavoring and as a preservative (by lowering water activity), but it is not a sequestering agent.
Therefore, EDTA is the most appropriate answer as a strong sequestering agent.
Step 3: Final Answer:
EDTA is the food additive used as a sequestering agent to prevent oxidative rancidity.