Determining Carbohydrates in Essential and Non-essential Foodstuffs using Ion Chromatography

Carbohydrates are synthesized in plants during photosynthesis using carbon dioxide, water and the energy from sunlight. They are one of the three macronutrients that provide the human body with energy. Due to the widespread use and importance of carbohydrates, their determination is of considerable interest in biological, environmental, clinical and medical research. Additionally, quality control of foodstuffs assures consumers’ top-quality carbohydrate supply.

The most commonly applied analytical techniques for determining carbohydrates are 1H-NMR, FT-IR, PAGE, MS along with GC and LC. While spectroscopic methods suffer from high instrumentation costs and need highly skilled operators, GC methods require time-consuming derivatizations. In view of these drawbacks, high-performance anion-exchange chromatography has increasingly been used for carbohydrate determination.
Sensitive and straightforward detection of the separated carbohydrates has long been a challenge. Several postcolumn derivatization reactions have been proposed for the spectrophotometric detection of carbohydrates. However, the improved sensitivity of these methods is offset by the labour‑intensive and often error-prone derivatization procedure.

This article describes a straightforward ion chromatographic method that uses isocratic elution and pulsed amperometric detection (PAD) to sensitively determine water-soluble polyols and sugar alcohols as well as mono‑, di- and oligosaccharides in essential and non-essential foodstuffs.