What gives onions their distinctive smell?
Ammonia
Sodium
Sulfur
Potassium
Fact: When onions grow, one of the things they absorb from the soil is sulphur. When an onion is damaged through cutting or crushing, a volatile sulfur compound is released into the air. The sulfur-containing compounds are the flavor precursors that give rise to the characteristic odor and flavor of onions. Although many sulfur compounds have a strong smell, the pure element is odorless. Sulfur compounds are also why onions make you cry, why asparagus gives urine a weird odor, why garlic has a distinctive aroma, and why rotten eggs smell so horrible.
Correct Answer: Sulfur