Ever send a bottle of wine back at a restaurant? If you weren’t just being a pretentious snob, then it was probably because the wine seemed “corked”—had a musty odor and didn’t taste quite right. Most likely, the wine was contaminated with a molecule called 2,4,6-trichloroanisole (TCA), the main cause of cork taint. But a new study by Japanese researchers concludes that you do not smell TCA directly; rather, TCA blocks up your sense of smell and distorts your ability to detect odors. The findings could help the food and beverage industry improve its products and lead to less embarrassment for both you and your waiter.