Keeping a Clean System
Consumers expect fresh and high-quality milk, and as producers, we want them to enjoy dairy products and trust where they come from!
Proper cleaning and sanitizing of your milking equipment is key for ensuring that quality milk is produced. When we talk about milking equipment, this is what we have in mind:
· Claws + inflations
· Pipelines
· Receiver jars
· Bulk tank
The objective of cleaning milking equipment is to prevent bacteria growth and remove lingering milk solids. These lingering and residual milk solids are called “soils” and are held on the inside of the milking system. Soils supply nutrients and areas for bacteria to grow, in return, reducing the effectiveness of your sanitizing chemical compounds. Ensuring that the milking equipment is getting a proper wash requires monitoring time, temperature, pH and agitation. The parameters of these will alter for each farm, but the principles remain the same.
There are four essential steps to proper cleaning and sanitizing. These include pre-rinse, wash, post/acid-rinse and sanitize. The most important ingredient in all of this is your water.
Water
Water is the main ingredient to any wash system, making up approximately 99% of the solution. This means you need to have water at the proper temperature from the times your vat fills to when it drains. Your water also needs to be high-quality, just like your milk. High quality water can save you money on chemicals as they will not have to also cleanse your water of impurities. Your local dealer can test your water by sending in samples.
When testing we are looking for:
· 1 to 6 GPG (grain per gallon) – in simpler words, a low hardness
· 0 to 300 buffers
· 0 to 500 PPM (parts per million) in TDS (total dissolved solids)
A few options to improve water quality are:
· Softeners (if water hardness is high)
· Filter (if water is high in iron)
· Detergent (if TDS is over 500 ppm)
Ensuring your facility has a hot water tank or system that fits the size of the milking equipment is crucial. A good rule of thumb that we have heard is 3.5 to 4.5 gallons of water per milking stall, but there are other factors that affect that rule. If your water sample comes back with high hardness or TDS, check the water heating system for limestone buildup. You may need to flush the unit or replace it.
pH
You can check your milking equipment cleaning cycles by using pH strips.
· Wash/detergent cycle - pH of 11 – 12
· Post/Acid rinse – pH of 2 – 4
· Sanitize - pH of 9 - 10
The 4 Steps:
Pre-Rinse
The pre-rinse cycle does most of the cleaning and should be done immediately after milking to remove about 70 percent of the soil. Lukewarm (100ºF to 110ºF) water should be used if adequate hot water supply allows for both a lukewarm pre-rinse and hot water wash. At the return line, your water temperature should still be 100ºF to 110ºF. If your rinse water temperature is below 93ºF, milk fat will be deposited on milking equipment surfaces. If the rinse water temperature is above 120ºF, it will allow remaining protein to create films. Protein films are not noticeable but as they build, they become yellow, and provide areas for bacteria to grow. The pre-rinse water contains residual milk and should not be re-cycled, the cycle should be run until the water appears clear and then should be drained.
Wash
A chlorinated alkaline detergent in either liquid or powdered form is used.
Alkaline
Milk fat does not mix with water. The pH breaks up lingering milk fat into tiny droplets, suspending the fat in the wash water.
Chlorine
Chlorine raises the solubility of any leftover protein and works to flush it out with the wash water.
The temperature of the wash cycle should be between 160ºF and 180ºF. The temperature of the chlorinated alkaline detergent should not fall below 120ºF. If this does happen, milk solids/protein may be left in the system. If the hot water system does not allow for the wash cycle to run this hot for 10-20 minutes depending on the size of the barn and parlor, it needs to be updated. Drain all chlorinated alkaline detergent wash solution before beginning the next step.
Post-rinse or acid-rinse
Rinse the milking system with cold or lukewarm acidified water for three to five minutes. The acid is used to send the milk line into a bacteria-static environment and to prevent minerals from collecting. When minerals collect on surfaces, milk stone develops, providing areas for bacteria to grow. The acid rinse balances the remaining residue from the wash cycle and helps to lengthen the life of rubber parts and gaskets.
Sanitize
State and federal regulations require that milking equipment be sanitized just prior to milking. This significantly reduces bacteria counts, especially if there is more than one hour between milkings. A chlorine-based sanitizer is used in warm water for about a five-minute cycle.
Additional Items to Evaluate:
Air Injector
Ensure the air injector is operating properly. The air injector creates turbulence to provide a scrubbing action. This ensures that all surfaces are getting a proper wash including the entire milk receiver/vats. The air injector forms slugs through the system to clean the pipeline. There should be three slugs per minute with a speed of 20-30 feet per second. Maintain and service the air injector regularly.
Receiver
When slugs of water hit the receiver, it should be one block. If the water is broken or no water is returned, something is wrong.
Dealer
Have a communicative relationship with your milk equipment dealer and service technicians, this is key to any system running and washing properly for quality milk production. Consider having your dealer do a wash analysis. This can be when you think there is a problem, or on a regular basis, anywhere from once a month to twice a year, depending on the dairy, their goals and if there are issues.
Supervise
There are benefits of having the washing system monitored. Having someone watch the system can catch simple mishaps like a hose coming off or an air leak, which can make the entire wash system fail. This can help to regulate consistency and quality of each wash.
Consumers and producers both want quality milk, and this can only be achieved when the milking system is operating at full efficiency!