Stephan VCM 44 - 10 Cleaning and Disinfection; Stages of the Cleaning and Disinfection Process

Cleaning and disinfection
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VCM 44
10. Cleaning and disinfection
The purpose of cleaning and disinfection is to break infection chains in the operation.
• Cleaning deprives microorganisms of their breeding medium by removing dirt (including
food remains).
• Disinfection inactivates or reduces the number of microorganisms that cause rotting or
poisoning of foodstuffs.
10.1 Stages of the cleaning and disinfection process
The precondition for an effective disinfection is always a thorough cleaning. Only in exceptional
cases and slightly soiled areas may a combined disinfection and cleaning be carried out, for
example with a mixture of aldehydes and surface-active quarternary (mineral) compounds.
In general, the cleaning and disinfection process follows the following stages:
• Precleaning with 40 to 50°C warm water for removal of the worst of the dirt.
• Cleaning with a cleaning solution heated to 60 to 80°C.
• Intermediate rinsing with warm water to remove cleaning solution and dirt-remains
• Disinfection.
• Rinsing with microbially pure water to remove remaining disinfectant.
10.1.1 Factors affecting the effectiveness of cleaning
The effectiveness of a cleaning process depends on the type of cleaning solution, the type of
dirt and that of the surfaces to be cleaned, as well as the effective temperature, effective time
and the relevant cleaning procedure.
Cleaning solutions
Water: The cleaning power of water may be fundamentally increased by numerous factors
such as high temperature, pressure, efficient time, mechanical dissolution of dirt or through the
addition of cleaning solutions.
During the removal of protein-containing dirt with water over 60°C, coagulated protein may
burn in on surfaces and should therefore quickly be removed with the appropriate cleaning ma-
terials.
Alkaline cleaning solutions: Soda lye, phosphates, Sodium hydroxide silicate. Soda lye has a
strong cleaning action against high-protein dirt and is therefore preferable for use in protein
production processes (meat, cheese etc.) The disadvantage of soda lye is its poor ability to
emulsify fat. The weaker alkaline reacting silicates have a better emulsifying capability.
The cleaning procedure appropriate to your machine has been described in the first
part of the operating instructions. (See "Daily cleaning and maintenance" on page
15.)