Alternatives to Salt Preservation: Preservation by Reducing Moisture Content
The first step in leather processing is the preservation or curing of hides and skins. Conventionally 40-50% of common salt is used to preserve the skins and hides, which leads to an increase in the Total Dissolved Solids (TDS) and chlorides (Cl) in the tannery effluent. Hence, researchers are demanded to look for alternative methods of preservation with less salt or salt-less preservation. In this paper, we report the results of the investigations carried out by reducing the moisture content of the skins using acetone and preserving them using low concentrations of boric acid. The properties and qualities of the crust leather are at par with the salt preserved skins. Also, this method offers significant reduction in TDS in the tannery effluent. The results obtained in this study substantiated that reducing the moisture content of the skins and hides to certain extent and applying boric acid helps in preserving the hides and skins for more than a month.
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