Citric Acid
Citric acid is an organic acidic molecule found naturally in nature, where one of the highest concentrations is in lemons and limes (8%). It's also produced by the fermentation of glucose. It contains 6 carbon, 8 hydrogen and 7 oxygen molecules, so the chemical formula is C6H8O7. Citric acid is added to many products for many different reasons from taste to cleanliness, because it is freely soluble in water and alcohol. This molecular compound is used many ways in society making it very valuable.
CH2-COOH HO-C-COOH CH2-COOH is the structural formula for citric acid, with the scientific term being 2-hydroxypropane-1,2,3-tricarboxylic acid. It contains 3 COOH bonds and an OH-(CH2)2 bond. In each COOH bond, the carbon has a double bond to an oxygen atom. In this particular molecule, each carbon of the COOH bond is connected in a single bond to another carbon atom. In all, there are 22 atoms and 22 bonds in a molecule of citric acid.
At room temperature, citric acid is a solid colourless crystalline powder that sometimes may appear white in colour. It is usually available as an anhydrous material (not wet) or monohydrate material (for every 1 citric acid, there is 1 water molecule). It easily dissolves in alcohol and water. Citric acid has a pH or approximately 3pH, making it mildly acidic due to the COOH bonds. This bond is known as the tricarboxylic acid. Citrus fruits often have a very sour, tart taste; this is because of citric acid. Lemons, limes, grapefruit, oranges and pineapples all naturally have high concentration of citric acid. However, citric acid is assumed to be in every living thing, no matter how small the amount.
There are many uses for citric acid. Most of its uses are for flavouring and preserving foods, candies and beverages. It gives foods a sour, bitter and tart flavour. It is also used to tenderize meats because citric acid breaks down the meat particles, making the meat softer. Citric acid also bonds with minerals and metals...