Using a Single Quadrupole Mass Spectrometer for Simultaneous Analysis of Sugars in Sugar Free Drinks

Significance of the Topic

The accurate quantification of trace sugars in sugar-free beverages is essential to ensure regulatory compliance and protect consumer health. Traditional detectors such as refractive index (RI) and evaporative light scattering (ELSD) often lack the sensitivity and selectivity required for low-level sugar analysis. Employing mass spectrometry coupled with hydrophilic interaction chromatography (HILIC) offers a powerful solution for detecting monosaccharides and disaccharides at sub-0.5 g/100 mL levels.

Objectives and Study Overview

This study aimed to develop and validate a rapid, sensitive method for simultaneous analysis of nine common sugars (rhamnose, arabinose, xylose, fructose, galactose, glucose, sucrose, lactose, maltose) in sugar-free drinks. A novel single quadrupole mass spectrometer (LCMS-2050) was coupled with HILIC separation to achieve baseline resolution and trace-level detection within a 22-minute run.

Methodology

The analytical protocol comprised:

• Sample Preparation: Degassing carbonated beverages, filtration through 0.2 µm membrane, 1 000× dilution with 75% aqueous acetonitrile.
• Chromatography: Shodex HILICpak VG-50 2D column (150 × 2.0 mm, 5 µm); mobile phase A: 2.5 mmol/L ammonium bicarbonate in water; B: 25 mmol/L ammonium bicarbonate in H2O/ACN (10:90); gradient from 99% B to 77% B and back over 38 min; flow rate 0.2 mL/min; column oven at 45 °C; injection volume 1 µL.
• Mass Spectrometry: LCMS-2050 single quadrupole system; ESI/APCI dual-mode ionization in negative polarity; SIM monitoring at m/z 149, 163, 179, 341; desolvation 400 °C; DL temperature 150 °C; interface voltage –2.0 kV.

Instrumentation

• Shimadzu LCMS-2050 single quadrupole mass spectrometer
• Shodex HILICpak VG-50 2D column
• Nebulizing gas supply and standard LC components (pump, autosampler, column oven)

Main Results and Discussion

Method performance was characterized by:

• Linearity: Calibration ranges tailored per analyte (0.005–10 mg/L) with correlation coefficients (r2) ≥ 0.998 across all nine sugars.
• Reproducibility: Six-fold injection RSDs < 1% for retention times and < 5% for peak areas.
• Recovery: Spiked samples at 0.5 mg/L showed 90–110% recovery for all sugars, demonstrating minimal matrix effects.
• Application to Drinks: Four commercial sugar-free beverages contained total sugars < 0.5 g/100 mL, meeting labeling standards; individual sugar concentrations were quantified down to low µg/mL levels.

Benefits and Practical Applications

This approach provides high sensitivity, selectivity, and throughput for routine quality control in the beverage industry. It enables reliable verification of sugar-free claims, supports product development, and can be extended to other low-sugar food matrices.

Future Trends and Potential Applications

Emerging directions include:

• Integration with tandem or high-resolution mass analyzers for enhanced specificity.
• Miniaturized and automated platforms for on-site testing.
• Expansion to novel sweeteners and oligosaccharides profiling.

Conclusion

The combination of HILIC separation and single quadrupole MS detection on the LCMS-2050 offers a robust, sensitive, and rapid solution for trace sugar analysis in sugar-free beverages. The method meets regulatory requirements and delivers high reproducibility and accuracy for routine laboratory implementation.