The topic of this blog post is the analysis of beer, a much loved beverage in many parts of the world! Here, I am pleased to feature the development of a robust, user-friendly, and fast on-line, SPE-UHPLC method that improves the traditional off-line SPE-HPLC analysis of isohumulones (link to Wikipedia page) in beer.
There are several advantages to the on-line sample preparation approach as sample preparation is a crucial aspect in food and beverage analysis:
- The on-line SPE method speeds up and automate labor-intensive sample cleanup and enrichment processes, making direct injection of untreated samples and unattended 24/7 operation a reality.
- The sample, in this case Frisian pilsener beer, was injected without any sample preparation.
- The workflow completed the analysis in 9 minutes as compared to 1 hour used by off-line SPE-HPLC analysis.
For those new to this analysis, monitoring isohumulones in beer during and after the brewing process is mandatory to control beer quality as isohumulones are responsible for the typical bitterness, flavor, and smoothness of beer, their antimicrobial effect leads to a sterile beverage, and their tensioactive character stabilizes the beer foam. (Isohumulones are generated during the boiling of wort and develop from the resins of hop.)
Like what you are learning?
The poster, Effective On-Line Sample Clean-Up and Analyte Enrichment for UHPLC Analyses, (downloadable PDF) describes using our dual, rapid separation HPLC system (Thermo Scientific Dionex UltiMate 3000 x2 Dual RSLC) which makes it easy to load an untreated sample onto an extraction column (using one pump) and then to wash the analytes from this column onto an analytical column using a second pump. (Check out the poster for some great schematics on this works.) The on-line SPE-LC wizard in our Chromatography Data System (CDS) software (Thermo Scientific Dionex Chromeleon 7.1 CDS software) makes it very easy to create and optimize the method and was used in to develop the solution.
The following analytical columns were used in the experiment:
- HPLC 1.9 µm column (Thermo Scientific Hypersil GOLD)
- SPE column 1: On-line sample SPE concentration column (Thermo Scientific SolEx HRP RSLC, 12–14 μm)
- SPE column 2: Thermo Scientific SolEx Acclaim C18 prototype, 5 μm, 2.1 × 20 mm
Do let us know if you have any questions on this poster in the Comments box below; we look forward to hearing from you!