Chill Out: A Cautionary Note On The Use Of Aqueous Treatments On Taxidermy

Written by Lu Allington-Jones, Senior Conservator at the Natural History Museum, London.

Whilst trying (not very successfully) to find a “cure” for fat burn (Figure 1), I made an unwelcome discovery: sometimes the shrinkage temperature of deteriorated skin is actually lower than room temperature. This means that the skin will irreversibly shrink as soon as any water-based treatments are applied.

Figure 1. Fat burn can cause skin to rip and specimens fall apart

Shrinkage temperature (Ts) is commonly used in leather conservation to determine the level of deterioration, and the effectiveness of treatments. Ts is the temperature at which 2 corian fibres immersed in water show simultaneous and continuous shrinkage activity. It shows the level of deterioration because it indicates destabilisation of collagen fibres. Ts of fresh skin is 65oC and in deteriorated leather this can be reduced to 30oC (Florian, 2006). Ts is measured by immersing samples of leather (or skin) in water and gradually increasing temperature until shrinkage activity is observed under a microscope (Larsen et al. 1996; Vest & Larsen, 1999). Continue reading