An acetate is a chemical compound derived from acetic acid, or ordinary household vinegar, the fermentation product of wine. The acid’s chemical structure consists of a methyl group (CH3) bonded to a carboxylic acid group (COOH). When acetic acid’s carboxylic acid hydrogen is stripped, the remainder, CH3COO-, is called "acetate" (shorthand, -Ac). There are both organic and inorganic forms of acetate. An example of the former is the ethyl ester, or oily fingernail polish remover, while sodium is an inorganic acetate. One of the best known and commercially most important polymers is the plastic polyvinyl acetate (PVA).
These acetic acid derivatives find very diversified applications. Along with its most important use as a buffering agent, sodium acetate can be found in a hospital setting, where it is used in the intravenous treatment of the low-sodium metabolic condition, hyponatremia. It is widely used as a flavoring agent in foods, including convenience treats, such as salt and vinegar potato chips. Interestingly, the same compound may be used to make an unusual form of hand warmer or heating pad. In waste handling, sodium acetate is used to neutralize acidic sulfuric acid contaminated water by means of the exchange reaction: NaAc + H2SO4 → Na2SO4 + HAc, or sodium acetate plus sulfuric acid gives sodium sulfate plus acetic acid.
A class of very important chemical reactions in nature is the acetate biosynthesis reaction. In this process, the chemical complexity of molecules is increased through the enzymatic addition of molecules of acetic acid, generally mediated by bacteria. This process is invoked to replace certain more costly synthetic reactions, particularly in the flavor industry. One example is the production of banana oil, which can be manufactured utilizing an engineered bacterium, Esicherichia coli. Just understanding the process is also proving valuable, enabling successful ongoing research into the preservation of delicate strawberry esters through the use of controlled atmosphere (CA).
Cellulose nitrate was once the standard film variety used by the motion picture industry — up until about the 1940s. That substance is unstable and highly flammable; cellulose nitrate fires are difficult to extinguish and produce dangerous gases, including corrosive nitrogen oxides and carbon monoxide. Many important films produced on cellulose nitrate have been forever lost due to degradative oxidation. More recent film stock employs cellulose acetate, the so-called "safety film." Unfortunately, even this improved film is subject to degradation, though it can be preserved for more than a century if stored under cold, dry conditions.
