tannic acid
LowTechnical/Scientific, Formal
Definition
Meaning
A bitter, astringent, yellow-brown polyphenolic compound, a type of tannin, naturally found in plants such as oak bark, tea leaves, and grapes.
A specific organic acid used commercially in tanning leather, in inks and dyes, and as an astringent in medicine. It also contributes to the taste and preservation of foods and beverages like wine and tea.
Linguistics
Semantic Notes
Specifically denotes the chemical compound (C76H52O46). Often used interchangeably with 'tannin' in non-technical contexts, though 'tannin' is a broader class of compounds.
Dialectal Variation
British vs American Usage
Differences
No significant lexical or grammatical differences. Both varieties use the term identically in scientific and industrial contexts.
Connotations
Neutral and technical in both varieties.
Frequency
Equally low-frequency and specialized in both regions.
Vocabulary
Collocations
Grammar
Valency Patterns
The [material/substance] contains tannic acid.Tannic acid is used to [verb] [noun].[Noun] is treated with tannic acid.The presence of tannic acid causes [effect].Vocabulary
Synonyms
Neutral
Weak
Vocabulary
Antonyms
Usage
Context Usage
Business
Used in contexts of leather production, winemaking, and the chemical supply industry.
Academic
Common in chemistry, biochemistry, botany, food science, and materials science papers.
Everyday
Rare; might be mentioned in discussions about tea, red wine astringency, or natural remedies.
Technical
Precise term in industrial processes (tanning, dyeing), laboratory chemistry, and pharmacology.
Examples
By Part of Speech
adjective
British English
- The tannic properties of the bark are notable.
- A tannic solution was prepared.
American English
- The wine had a distinctly tannic finish.
- They studied the tannic compounds in the sample.
Examples
By CEFR Level
- Some tea has tannic acid in it.
- The taste is from tannic acid.
- Tannic acid makes your mouth feel dry when you drink strong tea.
- The old recipe used oak bark, which contains tannic acid.
- Winemakers monitor tannic acid levels because they affect the wine's texture and aging potential.
- The chemist explained how tannic acid reacts with proteins during the tanning process.
- Analyses revealed that the historical manuscript's ink had degraded due to its high tannic acid content, leading to corrosion of the paper.
- The research postulates that the astringency elicited by tannic acid is a defensive mechanism evolved by certain plants to deter herbivores.
Learning
Memory Aids
Mnemonic
TAN your leather and make tea ACIDic: TANNIC ACID does both.
Conceptual Metaphor
THE BINDER (for its property of binding with proteins, e.g., in leather or taste perception).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid direct calque 'танная кислота'. The standard term is 'танниновая кислота'.
- Do not confuse with general 'кислота' (acid); this is a specific compound.
Common Mistakes
- Misspelling as 'tannin acid' (should be 'tannic acid').
- Using 'tannic' as a standalone noun (it is an adjective; the noun is 'tannic acid' or 'tannin').
Practice
Quiz
In which of the following contexts is 'tannic acid' LEAST likely to be discussed?
FAQ
Frequently Asked Questions
In precise chemical terms, no. Tannic acid is a specific type of tannin (a gallotannin). However, in everyday language, especially concerning food and drink, the terms are often used interchangeably.
In the small amounts naturally present in foods and beverages like tea and wine, it is generally safe. However, concentrated tannic acid can be irritating and is not meant for direct consumption.
Astringency refers to the dry, puckering sensation in the mouth caused by tannic acid binding with proteins in saliva. This property is also why it toughens animal hide into leather.
It is found in all true teas (from the Camellia sinensis plant), like black and green tea. Herbal 'teas' (tisanes) may contain different compounds unless they include tannin-rich plants.