Assessment of the potential suitability of selected commercially available enzymes for cleaning-in-place (CIP) in the dairy industry

Abstract

The potential suitability of 10 commercial protease and lipase products for cleaning-in-place (CIP) application in the dairy industry was investigated on a laboratory scale. Assessment was based primarily on the ability of the enzymes to remove an experimentally generated milk fouling deposit from stainless steel (SS) panels. Three protease products were identified as being most suitable for this application on the basis of their cleaning performance at 40°C, which was comparable to that of the commonly used cleaning agent, 1% NaOH at 60°C. This was judged by quantification of residual organic matter and protein on the SS surface after cleaning and analysis by laser scanning confocal microscopy (LSCM). Enzyme activity was removed/inactivated under conditions simulating those normally undertaken after cleaning (rinsing with water, acid circulation, sanitation). Preliminary process-scale studies strongly suggest that enzyme-based CIP achieves satisfactory cleaning at an industrial scale. Cost analysis indicates that replacing caustic-based cleaning procedures with biodegradable enzymes operating at lower temperatures would be economically viable. Additional potential benefits include decreased energy and water consumption, improved safety, reduced waste generation, greater compatibility with wastewater treatment processes and a reduction in the environmental impact of the cleaning process.

Keywords:

• enzymatic cleaning
• protease
• lipase
• dairy

Acknowledgements

This project is funded as part of the Science, Technology, Research and Innovation for the Environment (STRIVE) Programme 2007–2013. The programme is financed by the Irish Government under the National Development Plan 2007–2013 and it is administered on behalf of the DEHLG by the Environmental Protection Agency (EPA) which has the statutory function of coordinating and promoting environmental research.