New method for detection of
saccharides in soft drinks
High-speed analysis of monosaccharides and disaccharides using evaporative light
Author: Dr. Brigitte Bollig, Shimadzu Europa GmbH, E-Mail: firstname.lastname@example.org, Website: www.shimadzu.eu
Industrially processed sugar is often used as an ingredient by
the food and drinks industry. Four different types of sugar, also
known as carbohydrates or saccharides, can be hidden in the
food. In soft drinks, mono- and disaccharides are applied. A fast
gradient method with an ELSD-LT III detector was developed to determine
the content of fructose, glucose, sucrose, maltose and lactose.
Soft drinks contain water, natural or artificial flavorings and
sweeteners such as monosaccharides (glucose, fructose) or disaccharides
(sucrose, maltose or lactose). In general, the saccharides show
very narrow UV absorption wavelength range from 190 nm to 195
nm, because the hydroxyl group is the only major functional group
responding to UV absorption through its structure. Therefore, a
refractive index detector (RID) is commonly used for this analysis.
However, gradient elution cannot be used with RID because the baseline
drifting derived from the change of mobile phase composition during
the process is practically unacceptable. So, RID is not suitable for simultaneous
separation of compounds that show widely different retention
behaviors due to expected long analysis time without gradient elution.
Evaporative light scattering detector (ELSD) is a general-purpose
detector that can even discover components with no UV absorption,
such as carbohydrates. It detects the scattering light from the target
compounds after nebulizing and evaporating the mobile phase. ELSD
provides reduced analysis time and simultaneous separation of compounds
that show widely different retention due to applicability to
gradient elution. Monosaccharides and disaccharides are mainly analyzed
by anion-exchange chromatography or ligand-exchange chromatography.
However, analysis takes a long time.
Table 1: Analytical conditions.
Table 2: Repeatability of 250 mg/L (n=6).
Table 3: Concentration ranges of the calibration curves.
Table 4: Determination result of saccharides in soft drink A. Table 5: Determination result of saccharides in soft drink B.