Even though the extraction process is rather scientific, the acid itself is a natural, organic, non-test tube product. The citric acid listed in the ingredients of a tomato sauce is the same with the acid that that gives fruits like lemons and limes have this sour taste! At first, it was produced by dehydrating and crystallizing lemons, but later it was discovered that some strains of mold (such as Penicillium) produced it much more effectively.
As you can imagine, one of the main uses of citric acid is giving the foods a sour taste. We can find it in sour candies, soft drinks, juices and many prepared foods. It is also a very effective natural preservative and color additive, which is the reason that explains its addition to many canned and preserved products.
As for the citric acid in our closet? We can make cheese with its help! Because the citric acid is so dense, it is better than the lemon juice at separating the milk.
