Soaking

Abstract

The first step in processing is always soaking, whether for salted, dried or fresh rawstock. Salted stock needs to be rehydrated by removing the salt, dried hides simply need to be rehydrated and fresh hides need to be saturated with water. The soaking step(s), which are usually multiple in nature, serve to wash and clean the pelts and remove some of the natural components of the skin; chief among these is hyaluronic acid, which is easily removed from salted stock, but with difficulty from dried and fresh hides. The primary purpose is to provide a uniform medium for chemicals to be transported through the cross-section, to achieve uniform reactions to open up the fibre structure. In doing so, tanners have to be aware of the potential for bacterial growth and associated damage and/or the impact on the fibre structure and physical properties of the leather. The conditions of soaking can also affect the status of the fibre structure, with consequent effects on the quality of the leather.