Limiting microbial activity as an alternative approach of bovine hide preservation Part II: impact of developed formulations on leather quality and the environment

Authors: Sarker, Majher; Yosief, Hailemichael; Liu, Cheng Kung; Latona, Nicholas - Nick

Submitted to: Journal of American Leather Chemists Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/7/2019
Publication Date: 1/1/2020
Citation: Sarker, M.I., Yosief, H.O., Liu, C., Latona, N.P. 2020. Limiting microbial activity as an alternative approach of bovine hide preservation Part II: impact of developed formulations on leather quality and the environment. Journal of American Leather Chemists Association. 115:54-62.

Interpretive Summary: Animal hide preservation employs large amount of common salt (40-50% w/w on raw hide weight). The salt used for the hide preservation ends up being in wastewater and causes huge environmental pollution. To minimize the environmental pollution problem associated with the use of large amount of common salt, new animal hide preserving formulations have been developed containing environmentally friendly biocide and ~65% less amount of salt than the conventional method. The newly developed formulations were evaluated for their efficacy and found to be more effective in limiting microbial growth on hide surface than the commonly used formulation over 30 days of preservation period. The quality of the crust leathers produced from alternatively preserved hides were comparable to the leather produced from the traditionally cured hides. The environmental impact of the newly developed formulations was also evaluated by monitoring the leather processing effluents for total dissolved solids (TDS), chloride ions and other environmental pollution indicators. Over all the environmental impact of the inventive hide preserving formulations was less severe than the traditionally used formulation. Therefore, the newly developed formulations can be considered as environmentally benign alternative to the traditional hide curing process.

Technical Abstract: Wet salting of bovine hide commonly utilizes 95% saturated salt solution or 40-50% salt (w/w) on raw hide weight for preservation. The salt used for the hide preservation ends up being in wastewater and generates enormous environmental pollution. To minimize the environmental pollution problem associated with the traditional method of hide preservation, alternative formulations containing antimicrobial agents and less amount of common salt (35% saturated brine) have been developed. The alternative formulations were found to be more effective in deterring microbial growth than the traditional formulation as demonstrated by the total aerobic bacterial count of the preserved hide soaking liquor. The effect of the newly developed formulations on leather quality was assessed by analyzing the mechanical properties, scanning electron microscopic images, grain pattern and organoleptic properties of the finished leather. The quality analysis of the crust leather revealed that, the leather panels produced from the traditionally and alternatively preserved hides were comparable. The environmental impact of the newly developed formulations was also evaluated by monitoring the leather processing effluents for the pollution indicators such as total solids (TS), total dissolved solids (TDS), chloride content, Chemical oxygen demand (COD) and Bio-Chemical oxygen demand (BOD). Over all, the environmental impact of the newly developed hide preserving formulation was less severe than the traditionally used formulation. Since the newly developed formulations did not affect the quality of the leather produced and their impact on the environments is minimum, they could be considered as viable options for combatting pollution problems associated with the traditional salt curing method.