Chromatographic elution pattern of Soy sauce

Significance of the Topic

Understanding the distribution of sugars and polysaccharides in soy sauce is essential for quality control, flavor profiling and process optimization in the food industry.

Objectives and Study Overview

This application note demonstrates the use of a Shim-pack SUR-Na column in size exclusion and sodium-based ligand exchange modes to separate and quantify major carbohydrate constituents of soy sauce.

Methodology and Instrumentation

Carbohydrate components were analyzed using an aqueous mobile phase with two detection strategies to cover a wide molecular weight range.

Used Instrumentation

• HPLC systems: Nexera™ lite (refractive index detection) and Nexera™ reducing sugar analysis system (fluorescence detection)
• Analytical column: Shim-pack SUR-Na, 250 mm × 7.8 mm I.D., 8 µm; Guard column: Shim-pack SUR-Na (G), 50 mm × 7.8 mm I.D., 8 µm
• Mobile phase: Water at 0.7 mL/min (RID) and 0.6 mL/min (fluorescence)
• Column temperature: 80 °C; Injection volume: 10 µL
• Refractive index detector: RID-20A
• Post-column derivatization: 10 g/L L-Arginine and 30 g/L boric acid aqueous solution, reaction flow 0.5 mL/min, SUS reaction tube (8 mL × 0.5 mm i.d.), reaction temperature 150 °C
• Spectrofluorometric detector: RF-20Axs (Ex 320 nm, Em 430 nm)

Main Results and Discussion

Size exclusion mode separated high molecular weight polysaccharides from low molecular weight carbohydrates. Refractive index detection identified anionic species and polysaccharides at the exclusion limit, followed by glucose, galactose, arabinose, glycerol and ethanol near the penetration limit.

Fluorescence detection after post-column derivatization selectively quantified reducing sugars with improved sensitivity. Peaks corresponded to polysaccharides, glucose, galactose and arabinose.

Comparison of both modes highlights complementary coverage of molecular size and functionality. Robust performance under elevated temperature conditions was demonstrated.

Benefits and Practical Applications

• Rapid profiling of carbohydrates and polysaccharides in complex food matrices
• High selectivity and sensitivity for both neutral and reducing sugars
• Isocratic water mobile phase simplifies solvent management and reduces costs
• High-temperature operation accelerates analysis and improves peak resolution

Future Trends and Potential Applications

Integration with mass spectrometry for structural characterization;
Development of fast, high-temperature columns for high-throughput screening;
Extension to other food and beverage matrices for comprehensive carbohydrate analysis;
Automation of post-column derivatization workflows to enhance sensitivity and reproducibility.

Conclusion

The Shim-pack SUR-Na column in size exclusion and sodium-based ligand exchange modes, combined with refractive index and fluorescence detection, offers a powerful approach for detailed carbohydrate profiling in soy sauce. The method delivers reliable separation, high sensitivity and operational simplicity, making it suitable for routine quality control and research applications.

References

No external references were provided in the source document.