AP BIOLOGY

Detailed explanation-1: -The sour taste of foods and beverages is largely due to organic acids, including acetic, citric, malic, and fumaric acids in fruits and vegetables and tartaric acid in wine. Dilute solutions of many inorganic acids also taste sour. One example is the phosphoric acid in cola beverages.

Detailed explanation-2: -Fruits that contain more acid taste sour. Citrus fruits like lemons and limes have a large amount of acid, which accounts for their sour and at times bitter taste. Other sour fruits include kiwifruit, blackcurrants and raspberries.

Detailed explanation-3: -Acidic Foods have a Sour Taste – If you’ve ever tasted a lemon, you’ve had firsthand experience with the sour taste of acids. Citrus fruits, such as lemons, grapefruit, and oranges, all contain citric acid. Other foods such as vinegar and tomatoes also contain acids.

Detailed explanation-4: -An acid is a substance that donates hydrogen ions. Because of this, in an acidic solution there are more hydrogen ions than hydroxide ions. This means the more acidic a food is, the more hydrogen ions are available to trigger the sour taste receptors.