Cleaning is the removal of milk deposits from all milk contact points – internal pipework, milk meters, bulk milk tanks etc.
The purpose of cleaning and where appropriate disinfection, is to reduce bacterial contamination. Cleaning first removes milk residues left after milking and gives a significant reduction in micro-organism population. Disinfection using a product listed with a Pesticide Control Service (PCS) number is essential to finally reduce micro-organism populations to a safe level.
Milk residues consist of fats and proteins and may contain bacteria. This is an ideal environment for bacteria to multiply and grow. Another residue that originates from both milk and hard water, is scale such Calcium Phosphate, commonly known as Milkstone, or Calcium Carbonate, commonly known as water scale. Scales may harbour and protect bacteria from disinfectants.
Choosing the right chemical is essential, you cannot clean with a disinfectant and you cannot disinfect with a detergent.
Cleaning should always be performed as soon as possible after each milking.
In order to make cleaning as efficient as possible there are five important parameters to be considered:
Mechanical/Physical Action
• In circulation cleaners this is usually achieved by turbulent flow such that the liquid has a scrubbing effect on surfaces.
• In spray applications the kinetic energy of the spray flow will also give a scrubbing effect.
• Sometimes old fashion physical scrubbing such as the exterior of clusters is required.
Heat
• Aids the break-up of fatty soils and if the temperature is sufficiently high it will also aid in the destruction of micro- organisms.
• Heat is useful to break up proteins, but care is needed, if the temperature is too high, protein will simply burn on to surfaces and become more difficult to remove. The result will not only be a harbourage for micro-organisms, it could also directly result in milk contamination if burnt on debris has flaked off of surfaces into subsequent milking’s.
Contact Time
• Eventually you might clean with just hot water, but a very long contact time would be needed, plus a lot of expensive thermal energy. Using detergents at the right strength and temperature will reduce contact time.
Potable Water
• You cannot clean with dirty water. If the water is not fit to drink, it is not fit to clean with.
Chemicals (Detergents and Disinfectants)
• Choosing the right chemical is essential, you cannot clean with a disinfectant and you cannot disinfect with a detergent.
