Chromatographic elution pattern of fruit juice soft drinks

Importance of the topic

Reliable separation and quantification of sugars, organic acids, and water-soluble dietary fiber in fruit juice drinks are critical for quality control, nutritional labeling, and formulation development. The use of size exclusion combined with sodium-based ligand exchange provides a robust, aqueous-based approach that avoids organic solvents and enables simultaneous analysis of diverse molecular species.

Objectives and Study Overview

This application note evaluates the chromatographic performance of Shim-pack SUR-Na columns in size exclusion and sodium ligand-exchange mode for analyzing soft drinks containing fruit juice and added dietary fiber. The study compares samples with dietary fiber to standard 1% juice drinks, aiming to resolve organic acids, soluble fiber, and five key saccharides in a single run.

Methodology and Instrumentation

The workflow involves centrifuging each sample at 100 g for 3 minutes, diluting the supernatant tenfold with water, and injecting 10 µL onto the column. Chromatographic separation was achieved isocratically with water at 0.5 mL/min and 60 °C. Detection was performed by refractive index.

Used Instrumentation

• UHPLC System: Nexera™ lite
• Analytical Column: Shim-pack SUR-Na (250 mm × 7.8 mm I.D., 8 µm; P/N 228-59529-01) – two in series
• Guard Column: Shim-pack SUR-Na (G) (50 mm × 7.8 mm I.D., 8 µm; P/N 228-59529-02)
• Mobile Phase: Water
• Flow Rate: 0.5 mL/min
• Column Oven: 60 °C
• Injection Volume: 10 µL
• Detector: Refractive Index Detector (RID)

Main Results and Discussion

The chromatogram displays five distinct peaks:

• Peak 1: Organic acids (e.g., citric acid)
• Peak 2: Water-soluble dietary fiber
• Peak 3: Disaccharides (sucrose and maltose)
• Peak 4: Glucose
• Peak 5: Fructose

Retention times and peak shapes were consistent across fiber-fortified and standard juice drinks, demonstrating the column’s capacity to separate high- and low-molecular-weight species without baseline interferences.

Benefits and Practical Applications

• Fully aqueous operation reduces environmental impact and simplifies waste disposal.
• Single-run analysis streamlines quality control workflows in beverage manufacturing.
• High thermal stability (60 °C) ensures sharp peak shapes for carbohydrates and fibers.
• Sodium ligand-exchange mode enhances resolution of sugars and organic acids.

Future Trends and Applications

Advances may include integration with mass spectrometric detection for structural elucidation of dietary fibers, miniaturized column formats for high-throughput screening, and application to other food matrices such as dairy or plant extracts. Enhanced data processing algorithms could further automate peak identification and quantification.

Conclusion

The combined size exclusion and sodium-based ligand exchange mode on Shim-pack SUR-Na columns, operated with an all-water mobile phase, provides a straightforward, effective method for simultaneous analysis of organic acids, soluble dietary fiber, and key saccharides in fruit-based beverages. This approach offers significant benefits for routine quality control in the food and beverage industry.

References

• Shimadzu Corporation. Application Note ERAS-1000-0547, First Edition: February 2024.