Minimization of hazardous waste generated by CIP operations in the dairy processing industry

Final Report for the STRIVE project: 2007-FS-ET-2-M5

Summary: STRIVE Report 51 - Angela Boyce and Gary Walsh

Published: 2010

ISBN: 978-1-84095-348-0

Pages: 78

Filesize: 1,758 KB

Format: pdf


In dairy processing, effective cleaning of process equipment is essential for efficient plant operation and for the production of safe, quality dairy products. Such cleaning is generally achieved using sodium hydroxide (NaOH), caustic formulated detergents and acid at temperatures of up to 70–80°C. As such, cleaning has a negative impact on the environment. Cleaning has been reported to account for 30% of the energy use in dairy processing and is the largest contributor to overall wastewater volume in many plants. Detergents represent the greatest proportion of chemicals used in dairy plants and some of the chemicals used have adverse effects on human and ecosystem health and on the environment. Enzymes, which are biodegradable, have been exploited for cleaning in various other sectors, most notably in laundry and automatic dishwasher detergents.

Reported benefits include reduced usage of chemicals, reduced energy consumption due to milder operating conditions and reduced rinsing volumes, resulting in reduced water consumption and reduced generation of waste. Similar benefits could potentially be achieved by using enzymes for cleaning-in-place (CIP) in dairy processing. However, with the exception of cleaning membranes and cold milk areas of dairy plants, little attention has been given to the widespread application of enzymes for this purpose, particularly for cleaning heated components where significant and problematic fouling occurs. The main objective of this study was to determine if enzymes display realistic potential to replace (either partially or entirely) currently used environmentally significant CIP chemicals and, hence, reduce the overall environmental impact of CIP in dairy processing.

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