Analysis of oligosaccharides in beer using MALDI-TOF-MS

Area of Science:

• Analytical Chemistry
• Food Science
• Biochemistry

Background:

• Oligosaccharides are important carbohydrates in beer, influencing flavor and mouthfeel.
• Accurate analysis of oligosaccharides is crucial for quality control and understanding beer composition.
• Matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) is a powerful tool for analyzing complex carbohydrates.

Purpose of the Study:

• To systematically analyze oligosaccharides in different beer brands.
• To evaluate the effectiveness of various dihydroxybenzoic acid (DHB) isomer matrices for MALDI-TOF-MS analysis of beer oligosaccharides.
• To optimize experimental conditions, including dilution and cationization agents, for enhanced oligosaccharide detection.

Main Methods:

• Analysis of oligosaccharides in four beer brands (Cass, Hite, Budweiser, Miller).
• Utilized three dihydroxybenzoic acid (DHB) isomer matrices: 2,4-DHB, 2,5-DHB, and 2,6-DHB.
• Employed matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) under varying experimental conditions (dilution, cationization agents).

Main Results:

• The 2,4-DHB matrix did not yield observable ionised peaks for oligosaccharides.
• The 2,6-DHB matrix demonstrated superior performance compared to the 2,5-DHB matrix across most concentration ranges.
• Optimal detection was achieved using the 2,6-DHB matrix with a 4-fold dilution.
• Sodium chloride as a cationization agent enhanced ionization more effectively than sodium trifluoroacetate.

Conclusions:

• The choice of DHB matrix significantly impacts oligosaccharide detection in beer via MALDI-TOF-MS.
• The 2,6-DHB matrix, combined with appropriate dilution and cationization (sodium chloride), is highly effective for analyzing beer oligosaccharides.
• These optimized methods improve the accuracy and sensitivity of oligosaccharide profiling in malt-based beverages.