The semi-automated cleaning-in-place (CIP) integrated cleaning technique is very common in food manufacturing companies. It consists of removing residues and cleaning equipment without the need to disassemble the production line. However, there have been problems with high pH levels after cleaning in the dairy company under study. This situation can represent the risk of contamination of the products with chemical agents used in cleaning and cause production delays. This research aims to improve the CIP process of the company. The Six Sigma methodology based on the DMAIC cycle was used. 70.1% of the problems related to CIP are non-compliance with the conductivity limits during the soda and acid stages. The data was collected directly from the software used in the company to monitor the activity, and the 33 cleanings carried out in the evaporator for 3 months were considered. The capacity analysis indicates problems of both variation and compliance with the objective, with values Cp=0.71 and Cpk=0.03 for the soda stage, and Cp=0.53 and Cpk=0.09 for the acid stage. Through multiple regression analysis and ANOVA, the root causes of the conductivity problem were found: the work shift, CIP cycle duration, temperature, outlet flow, and DSI pressure. The improvement proposals are mainly focused on establishing and monitoring standardized protocols for different tasks of the CIP, which include: the determination of the concentration of chemical solutions, removal of mud from caustic soda solution, and cleaning inside the tubes. It is estimated that these measures can reduce the problem by 33.5%.

Keywords

Continuous improvement, Six sigma, Dairy, Standardization, and CIP.