Rapid monitoring of mono- and disaccharides in drinks, foodstuffs and foodstuff additives by capillary electrophoresis with contactless conductivity detection

A capillary electrophoresis (CE) procedure with contactless conductivity detection (C4D) has been developed for monitoring of neutral mono- and disaccharides in drinks and foodstuffs. The separation of a mixture of seven neutral saccharides (glucose, fructose, galactose, mannose, ribose, sucrose and lactose) employed a quartz capillary, 5 μm i.d., with an effective length of 18.3 cm, and 75 mM NaOH (pH 12.8) as the background electrolyte (BGE). The limit of detection (LOD) values obtained lied within a range from 0.4 μmol L−1 for lactose to 0.9 μmol L−1 for ribose, with a separation time shorter than 140 s. The procedure was successfully applied to determinations of saccharides in fruit juices, Coca-Cola, milk, red and white wines, yoghurts, honey and a foodstuff additive.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Small internal diameter of capillary. ► Electrophoretic separation of neutral saccharides in highly alkaline buffers. ► Contactless conductivity detection. ► Visualization of non-absorbing saccharides. ► Rapid food analysis.