Analysis of neuroactive amines in fermented beverages using a portable microchip capillary electrophoresis system

A portable microfabricated capillary electrophoresis (CE) instrument is used for the determination of neurologically active biogenic amines, especially tyramine and histamine, in fermented beverages. The target molecules are labeled on their primary amino groups with fluorescamine in a 10-min reaction, and the samples analyzed directly, producing a detailed electropherogram in only 120 s on a microfabricated glass CE device containing 21.4-cm-long separation channels. Tyramine was found mainly in red wines at <1-3.4 mg/L, while the histamine content of these samples ranged from 1.8 to 19 mg/L. The highest levels of histamine (20-40 mg/L) were found in sake. The analysis of samples drawn from grape crush through malolactic fermentation in four varieties of zinfandel red wines revealed that histamine and tyramine are produced during yeast and malolactic fermentation, respectively. Following malolactic fermentation, the histamine content in these samples ranged from 3.3 to 30 mg/L, and the tyramine content ranged from 1.0 to 3.0 mg/L. This highly sensitive and rapid lab-on-a-chip analysis method establishes the feasibility of monitoring neurologically active amine content and potentially other chemically and allergenically important molecules in our food supply.