Can Chromatography Provide a Way to Smell History?

Odour plays an incredibly important role in how we live, it is possible our least appreciated sense. But without smell our lives would be completely different and our perceptions of the world would be totally different. You only have to think back to the last time you had a cold and a blocked nose to understand the importance of odour.

All your food tasted different because you had no sense of smell — or rather the volatile organic chemicals (VOCs) released by the food whilst in your mouth couldn’t be detected by your smell receptors. So, knowing how important odours are to our lives — imagine if you could smell history, how much more interesting would it make the study of how our forefathers lived?

Smell the heritage

The importance of smells to understanding our cultural heritage is a relatively new idea. But knowing the importance of odours to our lives, a team from University College London (UCL) has set out to define historic smells in relation to heritage. And in a recent paper in the journal Heritage Science asked the question ‘Can this lead us to consider certain smells as cultural heritage?’

In the paper, they set out to investigate the links between olfaction and heritage and in doing so they developed a framework that could be used to investigate smells. They approached the task in three ways:

• theoretical analysis of role of olfaction in heritage guidelines to find out the type of places and situations where smell is important,
• how can smells be used to communicate with audiences in museums and other heritage situations, and
• an evaluation of the methods used to analyse and archive smells to allow their documentation and preservation.

The framework can be distilled to Significance Assessment—Chemical Analysis—Sensory Analysis—Archiving. They tested the method using historic paper as a case study and created a tool they called an odour wheel as the first step in documenting and archiving historic smells.

What’s that smell?

The key to analysing odours is that they are the result of VOCs — and chromatography is a key tool in analysing VOCs. Many methods for analysing VOCs use headspace solid phase microextraction (HS-SPME) with gas chromatography mass spectrometry (GC-MS). The use of SPME is discussed in the article, Direct Analysis in Real Time (DART®)-MS Analysis of Fentanyl and Related Analogues from Saliva Using Biocompatible Solid Phase Microextraction (BioSPME).

The team from UCL then created an odour wheel for old books. The idea is to help researchers identify odours and to bring some consistency to being able to describe those odours. That way, the heritage industry will have consistency in creating old smells and the public will have a better understanding of what history smells like.