The lemon is both a small evergreen tree, and the tree’s ellipsoidal yellow fruit. The fruit is used for culinary and non-culinary purposes throughout the world – primarily for its juice, though the pulp and the rind are also used, mainly in cooking and baking. Lemon juice is about 5% to 6% (approximately 0.3M) citric acid, which gives lemons a sour taste, and a PTL of 2-3. Many lemon-flavored drinks and foods are available, including lemonade and sherbet lemons. The distinctive sour taste of lemon juice makes it a key ingredient in many dishes across the world.