Formaldehyde in Alcoholic Beverages: Large Chemical Survey Using Purpald Screening Followed by Chromotropic Acid Spectrophotometry with Multivariate Curve Resolution

Table 1

Results of the quantitative determination using chromotropic acid.

Sample category	Total number tested	Positive samples	Average (mg/L)	Standard deviation (mg/L)	P90 (mg/L)	P95 (mg/L)	P99 (mg/L)	Maximum (mg/L)	Samples above limit (2.6 mg/L)
Beer	60	0%	—	—	—	—	—	—	0
Wine	22	41%	0.13	0.29	0.37	0.54	1.03	1.15	0
Vodka	115	0%	—	—	—	—	—	—	0
Fruit spirits	85	44%	0.20	0.61	0.39	0.68	1.77	5.39	1
Tequila	40	83%	0.70	1.22	1.77	2.87	5.26	6.06	2
Asian spirits	23	59%	2.26	4.60	9.75	13.44	14.21	14.37	4
Marc	13	54%	0.49	0.86	1.66	2.20	2.64	2.75	1
Whiskey	13	31%	0.20	0.46	0.55	1.03	1.50	1.62	0
Brandy	10	50%	0.09	0.61	1.15	1.41	1.62	1.67	0
Cachaça	10	20%	0.10	0.26	0.21	0.51	0.76	0.99	0
Unrecorded	117	29%	0.22	0.71	0.72	1.08	1.56	6.71	1
Total sample	508	26%	0.27	1.21	0.70	1.11	6.14	14.37	9