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November 20, 2020

Parosmia triggers

Investigating the chemistry behind parosmia triggers


Our Parosmia Facebook group share the same list of common foods that trigger parosmia with coffee, roasted meat, onions and garlic at top of the list. Some people even find water repulsive. But why is this and what do these triggers have in common?

In our webinar on 10 November, Dr Jane Parker, Director of The Flavour Centre and Associate Professor in the Department of Flavour Chemistry at the University of Reading, shared insight from her work into parosmia triggers.

What triggers parosmia?

Jane and her team are investigating the idea is that it's not the overall smell of a food that triggers parosmia, but specific chemical components, or flavour compounds, that are commonly found in many of the foods that cause that instinctive repulsion.

The problem is the complexity of the compounds. For example, it is estimated that more than 900 aromatic volatile compounds are produced when coffee beans are roasted, but only around 30 of them are perceived in the cup. And all of these compounds need to be in balance for us to enjoy the smell of coffee loved by so many.

Research techniques

Jane's laboratories use sophisticated equipment to break down the aroma profile of a particular odour into it's constituent molecules which can be hundreds within a particular sample. Participants with parosmia were then asked which of these individual smells were parosmic.

Although not everyone with parosmia reacted to the same triggers, the researchers have been able to identify ‘families’ of compounds that may trigger parosmia. This work could lead us to a greater understanding of what has changed within our olfactory systems to cause parosmia. We may even be able to create useful guide on foods and smells to avoid if you’re sensitive to a particular ‘family’.

The next stage of this research is to investigate foods that are less commonly reported to trigger parosmia to gain an understanding of the compounds in these, and to understand why they may not be a trigger.

You can watch the full webinar at YouTube/AbScentAnosmiaSupport





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