caffetannic acid compound

concept · 9 mentions

an acid found in coffee

Other senses of “caffetannic acid”

Connections

The concepts, people, and places this entity is most linked to by claims — node size is mention count, colour is type, dashed nodes are other senses of the same word.

Concept

Defining properties

is probably source of catechol
exists in green bean
is concentrated in outer layers of bean
can be extracted from coffee coffee ⟨using Krug's method⟩
forms compounds with lead acetate

Perspectives

Claims grouped by the voice that makes them.

William H. Ukers (author)

caffetannic acid is probably source of catechol
assertsneutralsource: coffee-pg28500
The compound, or compounds, known as "caffetannic acid" are probably the source of catechol
judge verdicts (2)
- groundedness 1.00 pass — The claim is directly supported by the passage. The opening sentence explicitly states: 'The compound, or compounds, known as "caffetannic acid" are probably the source of catechol,' which matches the subject, predicate, and object of the claim exactly.
- qualifier_fidelity 1.00 pass — All qualifiers are faithful to the passage. The viewpoint is correctly attributed to the author (passage presents this as the author's statement, not from a named source). The stance 'asserts' is appropriate as the passage uses 'are probably' to present this as an authorial assertion. Sentiment is neutral, matching the factual, technical tone of the passage. Time qualifiers are correctly null as no temporal scope is given. Context is appropriately empty as the passage provides no sense restriction. The quote is verbatim and directly supports the claim.
lead acetate forms compounds with caffetannic acid
assertsneutralsource: coffee-pg28500
Lead acetate forms three different compounds with "caffetannic acid"
judge verdicts (2)
- groundedness 1.00 pass — The claim is directly stated in the passage's opening sentence: 'Lead acetate forms three different compounds with "caffetannic acid,"' This is an exact match to the subject-predicate-object structure presented in the claim.
- qualifier_fidelity 1.00 pass — All qualifiers are faithful to the passage. The viewpoint is correctly attributed to the author (the passage itself makes the assertion). The stance is 'asserts' which matches the declarative nature of the statement. The sentiment is neutral, which is appropriate for a factual chemical claim. The time qualifiers are all null, which is correct since the passage provides no temporal information. The context is empty, which is appropriate since there are no contextual restrictions mentioned. The quote matches verbatim and directly supports the claim.

certain investigators

caffetannic acid exists in green bean
assertsneutralsource: coffee-pg28500
If one admits that caffetannic acid exists in the green bean; that upon oxidation it gives viridic acid; and that it is concentrated in the outer layers of the bean, as certain investigators have claimed
judge verdicts (4)
- groundedness 0.70 pass — The passage states this claim as a conditional hypothesis: 'If one admits that caffetannic acid exists in the green bean...' This is presented as an assumption rather than a direct assertion of fact, but the claim accurately captures the stated proposition with minor rewording of the conditional structure.
- qualifier_fidelity 0.50 fail — The stance qualifier is incorrect. The passage frames this with 'If one admits that caffetannic acid exists in the green bean' - presenting it as a conditional assumption made by 'certain investigators,' not as the author questioning it. The stance should be 'neutral' or 'stated' rather than 'questions'. Additionally, the viewpoint should be 'certain investigators' (the named source attributed in the passage), not 'author'. The quote is accurate but the qualifiers misrepresent how the passage presents this claim.
- groundedness 0.90 pass — The passage directly states that caffetannic acid exists in the green bean, presented as a conditional assertion ('If one admits that caffetannic acid exists in the green bean'). This is supported by the passage's reference to 'certain investigators have claimed' regarding its concentration in the outer layers, confirming the viewpoint attribution is accurate and grounded in the text.
- qualifier_fidelity 0.85 pass — The claim is largely faithful to the passage. The viewpoint correctly attributes the claim to 'certain investigators' as stated in the passage. The stance of 'asserts' is appropriate given the passage frames this as something investigators have claimed. The sentiment is neutral, matching the passage's tone. The quote is verbatim and supports the claim. However, there is a minor issue with the quote selection: the passage attributes the claim about caffetannic acid existing in the green bean to 'If one admits that' (a conditional/hypothetical framing) rather than a direct assertion by the investigators. The investigators are specifically credited only with claiming that it is 'concentrated in the outer layers of the bean.' A more precise quote should distinguish between the hypothetical admission and what the investigators actually claimed. This is a subtle but notable qualifier issue regarding what specifically the investigators claimed versus the broader conditional statement.
caffetannic acid is concentrated in outer layers of bean
assertsneutralsource: coffee-pg28500
it is concentrated in the outer layers of the bean, as certain investigators have claimed
judge verdicts (2)
- groundedness 1.00 pass — The claim is directly stated in the passage. The exact phrase 'it is concentrated in the outer layers of the bean, as certain investigators have claimed' appears verbatim in the text, with the passage explicitly attributing this assertion to 'certain investigators.'
- qualifier_fidelity 1.00 pass — All qualifiers are faithful to the passage. The viewpoint correctly identifies 'certain investigators' rather than attributing the claim to the author. The stance 'asserts' is appropriate for a claim about what investigators have said. Sentiment is neutral, matching the passage's factual tone. Time qualifiers are all null, which is correct since the passage provides no temporal information. Context is empty, which is appropriate as the passage does not restrict the claim to a particular sense or role. The quote appears verbatim in the passage and accurately supports the claim.

Krug

caffetannic acid can be extracted from coffee coffee ⟨using Krug's method⟩
assertsneutralsource: coffee-pg28500
Treat 2 grains of the coffee with 10 cc. of water and digest for 36 hours; add 25 cc. of 90-percent alcohol and digest 24 hours more, filter, and wash with 90-percent alcohol. The filtrate contains tannin, caffein, color, and fat.
judge verdicts (4)
- groundedness 1.00 pass — The passage directly describes Krug's method for extracting and measuring caffetannic acid from coffee. The entire procedure (treating coffee with water and alcohol, precipitating with lead acetate, and calculating caffetannic acid weight) explicitly demonstrates that caffetannic acid can be extracted from coffee using this method.
- qualifier_fidelity 0.60 fail — The viewpoint qualifier is unfaithful. The passage attributes the extraction method to 'Krug' (in the section title 'Caffetannic Acid--Krug's Method'), not to the author. The viewpoint should be 'Krug' rather than 'author'. Additionally, the quote provided ('The precipitate multiplied by 0.51597 gives the weight of the caffetannic acid') describes the quantification step, not the extraction itself, making it a weak supporting quote for the core claim that caffetannic acid 'can be extracted from' coffee.
- groundedness 1.00 pass — The passage directly describes Krug's method for extracting caffetannic acid from coffee, detailing a multi-step process involving water and alcohol digestion, filtering, and precipitation with lead acetate. The claim accurately reflects the passage's content without requiring outside knowledge or over-generalization.
- qualifier_fidelity 0.85 pass — The claim's qualifiers are mostly faithful. The viewpoint is correctly attributed to Krug, the stance of 'asserts' is appropriate, sentiment is neutral, and the context correctly specifies 'using Krug's method'. Time qualifiers are correctly null since the passage provides no temporal information. However, the quote is incomplete and somewhat misleading: while it does describe the extraction procedure, it doesn't explicitly state that 'The filtrate contains tannin, caffein, color, and fat' proves caffetannic acid can be extracted—the complete extraction involves the subsequent precipitation step with lead acetate to isolate the caffetannate of lead. The quote should ideally include the lead acetate precipitation step to fully support the extraction claim, or be shortened to just the initial treatment steps without implying completion of extraction.