Farming of the Australian saltwater crocodile (Crocodylus porosus) began in the 1980’s to protect the wild population. Since then they have become a highly valued, sought-after commodity within the high-end fashion industry, further strengthening the role of farming in the protection of the wild population. However, blemishes on the skin are not desired or accepted by the buyer, causing the skin to be down-graded, resulting in loss of income for the farmer. Leather is produced by a multi stage chemical and physical process that removes all skin components except collagen. This study explored the structural changes of collagen bundles during the tanning process using scanning electron microscopy (SEM) and Olympus Stream (version 1.9.1) analysis software on raw (unprocessed skin), incrust (also referred to as wet blue stage after chrome tanning), matte and gloss crocodile leather. By understanding how the tanning process affects the structure of collagen fibres, we can determine how blemishes are modified, and direct future research towards improving skin quality and ensuring profitability for the farmer.
The results showed that as leather is processed; the collagen fibres condense, decreasing in size within both the grain and the corium comparative to raw skin. Fibre condensation was minor for incrust and matte. However, was strongly visible when examining gloss leather. We calculated the average size of blemishes and characterised how different blemish properties lead to different organisation of collagen fibres. There were two key findings; the identification of how tanning affects collagen fibres, and how these fibres are arranged in different blemish types. This has provided insight into wound remodelling saltwater crocodiles. Further understanding what different crocodile blemishes are composed of, to improve skin quality and ensure the sustainability of the Australian industry.