Acidulant is a word that refers to a substance that is used to make a product more acidic. There are many synonyms for the word acidulant, including acidifier, souring agent, acidifying agent, and tartness enhancer. Acidifying agents are commonly used in food and drinks to add flavor or enhance taste. Some acidifying agents are produced naturally, such as citric acid and tartaric acid, while others are chemically synthesized, like fumaric acid and malic acid. Acidulants are added to foods like soft drinks, fruit juices, and candies to balance the sweetness and add a tangy flavor. Tartness enhancers are also used in cosmetics, toiletries, and pharmaceuticals to adjust pH levels.