propionic acid
Học thuậtThân thiện
Definition
Noun: 1. A liquid fatty acid: A colorless, oily liquid with a pungent, unpleasant odor. It is a naturally occurring carboxylic acid (C₃H₆O₂). 2. Chemical compound: A three-carbon fatty acid (propanoic acid) that is used as a preservative, especially in animal feed and human foods, and as a chemical intermediate.
Usage
- Propionic acid is a common preservative in baked goods to inhibit mold.
- The distinctive smell of Swiss cheese is partly due to propionic acid produced by bacteria.
- In industry, propionic acid is primarily manufactured for use as a feed and grain preservative.
Advanced Usage
- In Biochemistry: Propionic acid is a metabolic intermediate. For example, it is produced in the human gut by bacteria during the digestion of dietary fiber.
- Salts and Esters: The term is the root for related compounds. Its salts (e.g., sodium propionate, calcium propionate) and esters (e.g., methyl propionate) are widely used, deriving their names from "propionic."
Variants and Related Words
- Propanoic acid: The systematic IUPAC name for propionic acid.
- Propionate (noun): A salt or ester of propionic acid (e.g., calcium propionate).
- Propionyl (prefix): The acyl group (C₂H₅CO-) derived from propionic acid.
Synonyms
- Propanoic acid
- Methylacetic acid (an older, less common name)
Related Phrases / Terms
- Short-chain fatty acid (SCFA): Propionic acid is classified as a volatile, short-chain fatty acid, along with acetic acid and butyric acid.
- E280: The E number for propionic acid when used as a food preservative in the European Union.
Noun
- a liquid fatty acid found in milk and sweat and in fuel distillates