Malic acid is vegan. Malic acid is an organic compound that is produced by all living organisms. It’s one of the chemicals that give fruits their sour taste, especially green apples. Fruits – and some vegetables – contain the largest amounts of malic acid, so they are the best food to extract it from. Malic acid was first extracted from apple juice in the late 1700s by Carl Wilhelm Scheele. These days it is produced industrially in manufacturing plants to be used as a food additive.