Acetic acid is an organic acid found in nature. The compound is formed when ethanol, another organic compound, undergoes fermentation. Plants and animals can easily digest the compound, but at low and dilute concentrations. The acid is associated with vinegars, as it makes up 5 percent of the total vinegar solution. Its acidic and chemical properties allow it to be used in a variety of different ways; from producing solvents to pickling food.
Acetic acid's chemical structure reveals that it has an oxygen atom bonded to a hydrogen atom. This chemical bond gives the compound high polarity -- and because of this -- acetic acid is used to create a variety of different solvents. In its most concentrated form, the acid can act as a solvent for the production of the polymer, vinyl acetate. As a solvent, acetic acid is used to purify organic compounds during the process of recrystallization. Terephthalic acid, a compound used to make polyester for textiles, is first produced by using acetic acid as a solvent.
A variety of plant and animal tissues contain natural acetic acid and its weak acidic properties make it safe to digest at concentrations of 5 percent or less. Because of its acidity, vinegar is used in cooking to balance out the pH of recipes and meals -- and to provide a sour taste to dishes. Vinegar is used as a common solvent in pickling and preserving meat, fruits and vegetables. Vinegar is combined with salt to pickle. Its acidic properties create an uninhabitable environment for bacteria, which allow the food to stay safe for consumption for years to come.
Shampoos, conditioners, hair dyes, and other hair products all contain acetic acid as their neutralizer; which acts to control the pH of the solution and balance it out. Acetic acid is a weak acid, so it will not cause a drastic decline in pH levels; but rather, bring it to an ideal neutral level. Being a weak acid, the acetic acid keeps the different immiscible layers of compound in cream cosmetics together and prevents them from separating. Bacteria, viruses, and pathogens require a very specific pH range that is usually basic or neutral. Acetic acid is used in mouthwashes, toothpastes and rinses to get rid of these organisms. By decreasing the pH, the bacteria, virus, and pathogen can no longer survive.
In industry, acetic acid is applied to other chemical compounds used for the production of varnishes, top coats, paints, and acrylic lacquers. Acetic acid is first used to create other compounds that will be used for the production of these chemicals; it is not a primary ingredient.