Table 6.

The contents of TRP and some KP metabolites in different types of alcoholic beverages. 3HAA, AA, and CA were not included in a target list of the analytical methods utilized for quantitative analysis.

Sample	ABV * (%)	N	TRP	KYN	3HKyn	KYNA	XA	QA	PIC	Ref.
			CR (mg/L)	CR (µg/L)	CR (µg/L)	CR (µg/L)	CR (mg/L)	CR (µg/L)	CR (µg/L)
Beer	0–7.6	6	4.8–31.1	28.7–86.3	n.a.	16.9–52.0	n.a.	n.a.	n.a.	[18]
		19	n.a.	n.a.	n.a.	0.5–5.2	n.a.	n.a.	n.a.	[11]
Cider	2.5–13	2	n.a.	n.a.	n.a.	0.32	n.a.	n.a.	n.a.
Cognac	40–60	1	n.a.	n.a.	n.a.	0.06	n.a.	n.a.	n.a.
Liquer	~15	1	n.a.	n.a.	n.a.	0.1	n.a.	n.a.	n.a.
Mead	10–14	15	n.a.	n.a.	n.a.	9.4–38.1	n.a.	n.a.	n.a.
Red wine	<14	7	n.a.	n.a.	n.a.	3.3–10.9	n.a.	n.a.	n.a.
		4	1.0–1.8	<LOQ	n.a.	82.4–179.7	n.a.	n.a.	n.a.	[18]
Vodka	40–50	3	n.a.	n.a.	n.a.	0.07–1.6	n.a.	n.a.	n.a.	[11]
Whisky	40–50	1	n.a.	n.a.	n.a.	0.06	n.a.	n.a.	n.a.
Wine	<14	7	n.a.	n.a.	n.a.	1.4–4.7	n.a.	n.a.	n.a.
		4	<LOD–8.0	<LOD–14.8	<LOD	1.2–65.0	n.a	<LOD–307.1	<LOD–70.2	[116]
		-	n.a.	n.a.	n.a.	n.a.	~10.0	n.a.	n.a.	[117]

* alcohol by volume. n.a.—data are not available, the analyte was not included in the target list of the applied analytical method; CR—concentration range; <LOD—not detected; <LOQ—not quantified; and N—number of analyzed samples. AA—anthranilic acid; CA—cinnabarinic acid; 3HAA—3-hydroxyanthranilic acid; 3HKyn—3-hydroxykynurenine; KYN—kynurenine; KYNA—kynurenic acid; PIC—picolinic acid; QA—quinolinic acid; TRP—tryptophan; and XA—xanthurenic acid.