Definition

Noun: A clear, odorless, hygroscopic, syrupy carboxylic acid. It is a naturally occurring organic acid found in sour milk and in many fruits. It is also produced in muscle tissue during strenuous exercise when the body breaks down carbohydrates for energy without sufficient oxygen.

Usage

• General Chemistry/Biology: Used to refer to the specific chemical compound (C₃H₆O₃).
  • The fermentation process produces lactic acid.
  • Yogurt gets its tangy taste from lactic acid.
• Physiology/Exercise Science: Used to describe the byproduct of anaerobic metabolism in muscles.
  • A buildup of lactic acid can cause muscle fatigue and soreness.
  • Athletes train to improve their body's tolerance to lactic acid.

Advanced Usage

• "Lactic acid fermentation": A specific metabolic process by which glucose or other sugars are converted into cellular energy and lactic acid.
  • Cheese and sauerkraut are made using lactic acid fermentation.
• In cosmetics and skincare, lactic acid is used as an exfoliant.
  • This serum contains lactic acid to help smooth the skin's texture.

Variants and Related Words

• Lactate (noun): The anionic form (salt or ester) of lactic acid, often used interchangeably in physiological contexts.
  • Blood lactate levels are a key indicator of athletic performance.
• Lactic (adjective): Pertaining to or derived from lactic acid.
  • He experienced lactic acidosis after the marathon.

Synonyms

• 2-hydroxypropanoic acid (IUPAC chemical name)
• Milk acid (archaic/common name)

Related Phrases/Compounds

• Lactic acid bacteria: A group of bacteria that produce lactic acid as a major metabolic end product.
  • Lactic acid bacteria are essential for making yogurt.
• Lactic acidosis: A medical condition characterized by the buildup of lactic acid in the bloodstream.
  • The medication has a rare side effect of causing lactic acidosis.

Noun

1. a clear odorless hygroscopic syrupy carboxylic acid found in sour milk and in many fruits