Black’s Distillery in Peterborough wanted to know if their Heritage Vodka, made with Peterborough’s Red Fife wheat, is gluten free. For the answer, they approached Chemistry professor Dr. Kate Stewart.  

Professor Stewart is an expert in studying the chemical mechanisms by which sensing materials and analytes interact, so this was an opportunity to develop a new methodology tailored to sensing gluten molecules. 

Together with Chemistry graduate Benjamin Meeks ’19 (Otonabee College), Prof. Stewart designed a study to test the gluten content using the chemical analyses based in chromatography and spectroscopy. Using these approaches, the results showed the product was gluten free...but there was a catch.  

“Qualitatively we could say that there was no gluten in the vodka, meaning no gluten was measured above the detection limit of our test methods,” said Prof. Stewart. “However, we were unable to quantitatively determine the numerical value for the detection limit.  This meant that ultimately, we could not determine the amount of gluten, if any, was in the drink.” 

Gluten is hard to digest in more ways than one

The research team could not definitively say that the vodka is gluten-free because it is hard to test and obtain gluten concentrations in solution.

“Gluten is a really difficult substance to dissolve in solution,” said Prof. Stewart. “It seems like it would be a straight-forward experiment but, because of the difficulties creating a control solution by simply dissolving a known amount of gluten in a known volume of liquid, it’s actually hard to quantify the amount of gluten, if any is present.” 

This is a challenge that anyone wanting to label a beverage gluten-free (particularly one made from a substance containing gluten such as wheat) will face, and a flag for consumers looking for gluten-free drinks.  

Not the end of the road

Prof. Stewart says that while they hit that roadblock, the project still holds promise. 

“Although we didn't nail down the detection limit, we have results that show, qualitatively, that gluten is present in the starting materials (Red Fife wheat) and gluten is no longer present in the final product,” said Prof. Stewart. “This is a positive outcome that helps guide the future of developing a test or methodology for testing the gluten content of drinks. We didn’t exhaust all options for the project, and can look to other methods, such as mass spectrometry, to get more definitive answers.” 

Important lessons in real-world research

For Benjamin, the project was a great opportunity to develop important skills in research, and gain a better understanding of the work of researchers. 

“This project let me use skills in analytical chemistry that I had developed throughout my classes, but the skill I developed most from that was perseverance because of how we needed to adjust our approach when we encountered delays or roadblocks in methodology.” 

Learn more about Chemistry programs at Trent University.