Real or fake? Aroma Profiling of Plant-Based Alternative Foods using Sorptive Extraction and GC×GC–TOF MS

Terry Buckland, Schauenburg Analytics, Bridgend, UK (tbuckland@schauenburganalytics.com)
Laura McGregor, Sepsolve Analytical, Peterborough, UK
Ryan Sutherill, Sepsolve Analytical, Peterborough, UK
Rachael Szafnauer, Markes International, Bridgend, UK

Plant-based meat and dairy substitutes have increased in popularity in recent years, and a goal for food producers is to create a product that mimics the sensory experience of the real thing.

Unfortunately, this is a challenging prospect due to the complexity of the aroma profiles and the wide range of matrices involved. Additionally, odour thresholds will span many orders of magnitude, meaning that sensitive analysis is also essential to ensure that trace, yet potent, aroma-active compounds are detected.

Here, high-capacity sorptive extraction probes were used to provide a larger volume of stationary phase (65 μL) compared to traditional solid-phase microextraction (SPME) (~0.5 μL) for higher sample loadings. When used in combination with trap-based focusing this provides enhanced sensitivity and improved chromatographic performance. In addition, the robust probe design allows both headspace and immersive sampling to tackle a wide range of matrices.

However, improved extraction capability often results in more complex chromatograms. We demonstrate the use of comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC–TOF MS), which offers enhanced separation of complex aroma profiles, allowing confident identification of compounds that would co-elute in conventional 1D GC.

Finally, sophisticated data analysis is required to quickly identify subtle differences between aroma profiles. In this case, an untargeted tile-based approach was used to compare all of the raw data automatically, without time-consuming pre-processing. Importantly, chromatographic alignment is included to account for retention time drift over the course of the study and minimises the risk of false hits.

In this poster, we demonstrate the performance of the described workflow to compare the aroma profiles of plant-based burgers.