Otto Hermelin is Associate Professor in the Department of Geological Sciences at the University of Stockholm. He is conducting research into the maturation process in whisky and how temperature and humidity affect the maturation in four of Islay's bonded warehouses. He is monitoring casks at Bruichladdich, Kilchoman, Ardbeg and Bunnahabhain distilleries of which ten are located in Bruichladdich Warehouse 14.
Back in Sweden he monitors the maturation process in casks of different sizes (30, 100 and 200 litres) in two different warehouses at Mackmyra distillery.
Samples are drawn twice a year from casks located in different physical locations in the distillery warehouses. Some of the casks are located at ground level, some at mid-height and some at the top of the racks. All the casks were filled at the same time from the same batch of new-make spirit. The majority are first fill bourbon casks, but at Bruichladdich some originally held French red wine.
Sensors recording the temperature and humidity at the different positions are in place and these store the information which is then downloaded to computers. These sensors monitor changes in temperature and humidity every hour. The differential between the temperature and humidity levels at the top and bottom of these racks, and also variations due to the physical location of the warehouses, is considerable.
The samples from the maturing whisky are taken back to the laboratories in Stockholm University by Otto Hermelin and subject to detailed chemical and spectroscopic analysis of both organic and inorganic compounds and how these vary over time as the whisky matures. The research project is expected to last ten years.
We hope to bring you regular updates as the study progresses.