Understanding collagen degradation patterns in parchment, leather, and commercial collagen using proteomics

The study of ancient proteins provides invaluable insight into past cultures and societies. Proteins undergo various degradation processes which make their lifespan highly variable. Collagen, the main protein in hide materials, is a particularly useful protein to study due to its stability and long survival. Understanding the degradation patterns of collagen is an important step to understand the use and conservation history of archaeological and historical objects made from animal skins such as parchment and leather which can be further applied to the leather and food industries. This thesis aims to explore available tools in palaeoproteomics to assess (a) changes in proteins present in hide materials caused by manufacturing processes and use history, and (b) the relevance and application of palaeoproteomics methods to the modern-day processing of collagen in the food industry. This thesis demonstrates two novel uses of the ZooMS methodology: (1) as a tool for the preliminary identification of proteins from milk, egg, and wheat origin alongside species identification and (2) when compared to current methods, as a faster and more accurate method of quality control in the processing of collagen in the food industry. Additionally, the development and application of a targeted method for the determination of piscine gelatine, aided by data derived from palaeoproteomics studies, which aims to support enforcement in food safety, is presented. Finally, this thesis analyses the degradation patterns of collagen based on the deamidation of glutamine on a variety of hide materials processed in varying pH environments. The results highlight the need for studies on the kinetics of deamidation under varied conditions to further our understanding of the forces behind protein degradation and damage. Together, the results of this thesis evidence the importance of the correlation of palaeoproteomics studies to commonly used methods in associated fields for the preservation of cultural heritage.