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Esterification is the general name for a chemical reaction in which two reactants (typically an alcohol and an acid) form an ester as the reaction product. Esters are common in organic chemistry and biological materials, and often have a pleasant characteristic, fruity odor. This leads to their extensive use in the fragrance and flavor industry.
An example of an ester formation is the substitution reaction between a carboxylic acid (R−C(=O)−OH) and an alcohol (R'OH), forming an ester (R−C(=O)−O−R'), where R and R′ are organyl groups, or H in the case of esters of formic acid.
Most fatty alcohols in nature are found as waxes, which are esters of fatty acids and fatty alcohols. [1] They are produced by bacteria, plants and animals for purposes of buoyancy, as source of metabolic water and energy, biosonar lenses (marine mammals) and for thermal insulation in the form of waxes (in plants and insects). [3]
The most commonly used alcohol is methanol, producing fatty acid methyl esters (FAME). When ethanol is used fatty acid ethyl esters (FAEE) are created. Other alcohols used for the production of biodiesel include butanol and isopropanol. Fatty acid ethyl esters are biomarkers for the consumption of ethanol (alcoholic beverages). [1] [2] [3]
These esters are derived from C12-C20 fatty acids. The remaining content of beeswax are wax acids (>C20) and paraffins. In 1976, an estimated 10,000–17,000 tons were harvested. The primary use was in candles. The esters in carnauba wax consist of ca 20% cinnamic acid derivatives, which may be related to the hardness of this wax. [1]
In organic chemistry and biochemistry esters are the functional group (R'-COOR") consisting of an organic radical united with the residue of any oxygen acid, either organic or inorganic. An ester is a product of the reaction of an acid (usually organic) and an alcohol (the hydrogen of the acid R-COOH is replaced by an alkyl group R").
A common example is sodium lauryl sulfate, with the formula CH 3 (CH 2) 11 OSO 3 Na. Also common in consumer products are the sulfate esters of ethoxylated fatty alcohols such as those derived from lauryl alcohol.
As a result, ethyl acetate—the ester of ethanol and acetic acid—is the most abundant ester in wines. Other combinations of organic alcohols (such as phenol-containing compounds) and organic acids lead to a variety of different esters in wines, contributing to their different flavours, smells and tastes.