How to Perform Clean-In-Place (CIP) in a Brewery: A Quick Guide

Maintaining a clean and sanitary environment is crucial in any brewery to ensure the quality and safety of the beer produced. Clean-In-Place (CIP) systems are essential tools in achieving this. In this guide, we will explore how to perform CIP in a brewery and discuss the concept of the Sinner's Circle, a fundamental principle in cleaning and sanitization processes.

What are Clean-In-Place (CIP) and Clean-Out-Of-Place (COP)? 

In brewery sanitation, it's crucial to understand the difference between Clean-In-Place (CIP) and Clean-Out-of-Place (COP) methods. Clean-In-Place (CIP) refers to the automated cleaning process where equipment is cleaned and sanitized without being disassembled. This method uses a combination of water, chemicals, and heat circulated through the system to remove residues and kill microorganisms, making it highly efficient for cleaning tanks, pipelines, and other fixed systems.

Clean-Out-of-Place (COP), on the other hand, involves disassembling equipment and manually cleaning each part separately. This method is essential for items that cannot be effectively cleaned in place, such as manway shadows, vessel ports, smaller components, gaskets, and certain types of fittings. COP typically involves soaking parts in a cleaning solution and using mechanical action like scrubbing to remove residues. While CIP is time-saving and reduces labor, COP ensures thorough cleaning of components that CIP might miss, ensuring all parts are free from contaminants and ready for reassembly and use. Both methods are critical in maintaining the overall hygiene and operational efficiency of a brewery.

Steps to Perform CIP in a Brewery

1. Preparation and Safety

• Safety First: Ensure all personnel are equipped with proper protective gear, including gloves, goggles, and aprons. Working with chemicals can be hazardous, so it's crucial to follow safety protocols.
• System Check: Verify that all equipment is in good working condition and that all connections are secure. Check for any signs of wear or damage that could interfere with the cleaning process.

2. Pre-Rinse

• Water Rinse: Start with a pre-rinse using warm water (typically between 35°C and 45°C). This initial rinse removes loose soil and residues, helping to prepare the surface for the application of cleaning chemicals. This step can significantly reduce the amount of soil that needs to be removed by the cleaning agents.

3. Cleaning Solution Application

• Chemical Cleaning: Circulate an appropriate cleaning solution through the system. The choice of chemical depends on the type of residue:
  • Alkaline Detergents: Used primarily for organic residues like proteins, fats, and carbohydrates. Caustic soda (sodium hydroxide) is a common alkaline detergent that effectively breaks down these materials.
  • Acidic Detergents: Used for inorganic residues like mineral deposits (e.g., beerstone, which is calcium oxalate). Phosphoric acid or nitric acid are typical acidic detergents used in breweries.
• Concentration and Temperature: Ensure the cleaning solution is at the correct concentration and temperature. Alkaline solutions are often used at 1-2% concentration and temperatures around 60°C to 80°C. Acidic solutions might be used at lower concentrations (0.5-1%) and slightly lower temperatures (50°C to 60°C).

4. Post-Rinse

• Rinsing: After circulating the cleaning solution, thoroughly rinse the system with water to remove any remaining chemicals. Use potable water at a temperature similar to the cleaning solution. This step ensures no residual cleaning agents are left, which could contaminate the beer. Very the pH of the rinse water with a meter or strips to ensure that it is fully rinsed.

7. Validation

• Inspection and Testing: After the CIP cycle, inspect the equipment visually for any signs of remaining soil or residue. Check under manways and in side ports as well. Additionally, perform microbial tests, such as swab tests or ATP (adenosine triphosphate) tests, to ensure cleanliness and sanitation standards have been met. Documentation of these tests is essential for quality control and regulatory compliance.

Understanding Sinner's Circle in CIP

Figure 1 - Sinner's Circle Key Factors

The Sinner's Circle, also known as the Sinner's Circle of Cleaning, is a model that describes the four key factors influencing the effectiveness of cleaning processes: Time, Action, Chemical, and Temperature (TACT). Balancing these factors is crucial for optimizing the CIP process. All four parts are necessary for effective cleaning.

• Time: The duration the cleaning agents are in contact with the surfaces. Longer contact times generally improve cleaning efficacy but must be balanced with operational efficiency.
• Action: The physical force or agitation applied to aid in soil removal. In CIP systems, this is often achieved through the circulation of cleaning solutions at high flow rates or by using spray balls to create turbulence.
• Chemical: The type and concentration of cleaning agents used. The correct selection and concentration of chemicals are vital to breaking down and removing specific types of residues.
• Temperature: The heat applied during the cleaning process. Higher temperatures generally enhance the effectiveness of cleaning agents but must be controlled to prevent damage to equipment and ensure safety.

Figure 2 - Balancing The Elements 

When balancing the elements of Sinner's Circle, increasing one variable allows for the reduction of others while still achieving effective cleaning. For example, raising the temperature of the cleaning solution can shorten the necessary contact time or reduce the concentration of chemicals needed. Similarly, enhancing mechanical action through higher flow rates or more agitation can decrease the amount of chemical required or the temperature of the solution. This flexibility allows for optimizing the cleaning process to fit specific operational needs and constraints, ensuring thorough and efficient sanitation.

Conclusion

Implementing an effective Clean-In-Place (CIP) system in your brewery is essential for maintaining the quality and safety of your beer. By following the steps outlined above and understanding the principles of the Sinner's Circle, you can ensure your brewing equipment is thoroughly cleaned and sanitized, preventing contamination and ensuring a great-tasting final product.

Further Reading

Rench, R.J. (2019) Brewery Cleaning: Equipment, procedures, and troubleshooting. St. Paul, MN: Master Brewers Association of the Americas.