ARS | Publication request: Microbiological and near IR studies of leather from hides presoaked in formulations that can remove hardened bovine manure

Submitted to: Journal of American Leather Chemists Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 31, 2012
Publication Date: N/A

Interpretive Summary: One major problem faced by the hides and leather industry is the damage caused by the mechanical stress from the adobe type manure that stuck to the hides. The decomposition of hides due to bacterial growth from manure contaminations can lead to low quality finished leather products. The two most common ingredients of a soaking solution that the hides and leather industry are using to clean up dirty hides are detergent and antibiotic. It was observed that this standard industry soaking solution is capable of completely eliminating the microbial growth when the antimicrobial property was investigated. Unfortunately, even the high concentration of detergent and antibiotic it consist is not efficient in removing adobe type manure. There is a continued need to improve the cost and performance efficiencies of these solutions and to make them more environmentally friendly. In this study, we developed and tested new soaking formulations using only a fraction of the standard soaking solution that incorporated the inexpensive crude glycerol from biodiesel production and the eco-friendly antimicrobial biobased detergents (called sophorolipids). The results showed that the new soaking solutions are effective in softening hardened manure and in inhibiting bacterial growth. The outcome of this research is valuable to the hides and leather industry to improve the handling and processing of hides and the quality of the leather derived thereof.

Technical Abstract: The standard soaking solution that the industry has been using in cleaning dirty hides is usually composed of a high concentration of antibiotic and surfactant. It is observed to be good in eliminating the microbial contamination (~99.9%) presented on the hides but is not as efficient in removing the adobe-type manure. In this study, we report the microbial growth of the different manure soaking solutions and the chemical changes at the surface of the hide after soaking. The microbial growth is monitored by inoculating on agar plates the washings from the manure soaked in different manure removal formulations. It was observed that a new eco-friendly solution composed of only a fraction of the standard soaking formulation is capable of eliminating about 70% of the microbial growth when 10% crude glycerol and 1.0% sodium carbonate are included in the solution. The crude glycerol alone has shown microbial growth compared to the pure glycerol that exhibited no growth but the other ingredients present in crude glycerol could have enhanced the efficiency in softening and eventually removal of adobe type manure.