10 SIP Tips To Ensure Effective Sterilization Of Food-Processing Equipment

By Melissa Lind, contributing writer

Both Steam-In-Place and Clean-In-Place methods are designed for automated cleaning and sterilization of food processing equipment without the requirement of dismantling and reassembly of the machinery. A common mistake that some manufacturers make is in the order of operations.

Clean-In-Place (CIP) is an automated method employed to remove particulate matter or food soil after processing. Steam-In-Place (SIP) operations are used to kill microorganisms in the same system. Some food processors employ SIP operations prior to CIP, which can reduce the effectiveness of the sterilization procedure. Both processes have their value in safety assurance in the food processing and manufacturing industry, but more attention is often paid to the CIP process. Your company may benefit from some SIP design and process tips to ensure your method is effective.

1. CIP operations should always be performed prior to SIP processes. CIP removes food remnants and soils so that further microorganism growth cannot occur
2. Process flow of CIP and SIP should be in the same physical direction to enable use of the same pipe and drain lines, avoiding dead ends and low-collection points
3. Systems should be designed so the steam supply enters the equipment line at the highest or earliest point possible to ensure complete saturation by pushing out resident system gases
4. Steam trap temperature sensors and blocking valves should be installed at the lowest physical point in the system to allow for monitoring at those spots where temperature may be cooler
5. High point bleeds should be in place to allow for complete elimination of air at the end of the sterilization process
6. Parallel steam paths should be avoided to eliminate the possibility for pressure variations in different paths resulting in lack of complete sterilization
7. Ensure that the steam supply pressure and temperature at header is up to process specifications
8. A time delay should be allowed after systems are fully pressurized and saturated with steam to allow components to achieve required temperature
9. Once thermal hold has brought equipment to temperature, active steam flow should be continued for time required according to system standards
10. Ensure that once SIP process is complete, system sterility is maintained as condensate is drained from system by establishment of sterility boundary

Not all manufacturers employ SIP as a separate process. Some choose an additional step of chemical sterilization rather than steam. However, for maximum effectiveness, both methods require that the CIP process be performed before sterilization to reduce the chance that any microorganism contamination will remain in the food line.