I. What are the necessary conditions for cleaning milking equipment and cold cylinders?
No matter what kind of milking equipment or cold cylinder, to achieve good cleaning effect, four factors must be guaranteed: a certain mechanical scouring force, appropriate temperature, effective detergent, and sufficient contact with the surface of the equipment to reach a certain time before all dirt can be removed. To achieve the above four elements, the following conditions must be met:
1. Cleaning water must meet the drinking water standard.
2. The capacity of the heater (electric heating, boiler or solar energy) must be large enough.
3. It must have a temperature indicator and work properly.
4. Choose an effective cleaning agent.
II. Cleaning should pay special attention to the quality of water
Water is the necessary medium for equipment cleaning and plays multiple roles in cleaning. It is a solvent and diluent of lactose and chemical detergent, and a detergent that pushes the turbulence of detergent across the inner surface of the system. Water is also the medium of heat conduction, which accelerates the chemical reaction of cleaning the whole system through heat energy and eventually removes the dirt from the equipment. Therefore, the cleaning water for ranch equipment must meet the hygienic standards; it must have enough heat and water volume and flushing strength to play these roles. Groundwater is used in most ranches in China. Due to environmental pollution and many restrictive factors, the quality of equipment cleaning water is not stable. In recent years, the increase of sediment content in groundwater is also very common. It is necessary to monitor the water quality of ranches once or twice a year. Ensure that there is no contamination of feces, heavy metals or other toxic and harmful substances.
The equipment, detergent and cleaning method used in milk production in each ranch will be different. The requirements of raw milk for processing dairy products in milk processing enterprises are also different. Anyway, any cleaning equipment must have some cleaning characteristics. The best cleaning system for cleaning, disinfecting and milking equipment should have the following characteristics:
1. Remove all surface dirt.
2. Killing or removing bacteria.
3. No corrosiveness to equipment.
4. Minimum time and energy consumption.
5. Safety in food production and residue.
6. It is safe for the environment.
III. Common cleaning methods in the world
The most common cleaning method is the three-step cleaning method with alkali washing as the main method, which is pre-rinse -- alkaline cleaning with chlorine--post-rinse. Determination of pickling frequency based on water hardness. This cleaning method is widely used in most European and Asian countries, such as the Netherlands, which is the standard cleaning method for ranches. But Danish traditional cleaning methods are pre-rinse - alkali rinse - cold water rinse - acid rinse, rinse with pure cold water before milking. The most common cleaning steps in the United States are pre-rinse - alkaline rinse-acid rinse and pre-milking disinfection. In New Zealand, pickling is the main cleaning method, which is boiling water with acid detergent, rinsing with cold water and regular alkali washing.
In short, what cleaning methods are adopted depends mainly on the customary and legal requirements of different countries, as well as the energy costs for heating water, cleaning costs and cleaning conditions.
I. Common cleaning problems
Although most dairy farms in China have posted wall charts of cleaning procedures or standard cleaning procedures, there are large discrepancies in the actual operation. The most common problems are insufficient water temperature, or the use of solar water temperature can not guarantee constant, or inadequate capacity of electric heaters. Unable to meet the requirement of water temperature is the enemy of cleaning. The inadequate cleaning temperature will lead to equipment fouling, increase the number of bacteria in milk, decrease the quality of milk, and even be rejected by dairy factories, resulting in direct economic losses of dairy farms. Common cleaning problems in cow farms mainly include the following aspects:
1. Insufficient water temperature
Normal temperature cleaning agent requires that the temperature of alkali washing water reach 75-85 ℃, and at the end of the cycle cleaning, the water temperature should not be lower than 40℃. Otherwise, the milk fat dirt in the cleaning water will coagulate and precipitate again, and adhere to the surface of the equipment to form milk dirt. In actual production, the capacity of boilers in the ranch is often smaller than the actual demand, especially the electric heating equipment is generally small, or the hot water used for cleaning equipment in ranch has increased many uses, resulting in insufficient hot water. The temperature after circulation drops to below 40 ℃, resulting in serious fouling of equipment, and the quality of milk is greatly reduced.
2. Incorrect cleaning procedure
After milking, the equipment should be pre-rinsed with warm water at 40-45 ℃. The rinsing water should be discharged directly and not recycled. At this time, 95% of the milk residue in the equipment should be washed away. The first pre-rinse with cold water is easy to cause milk fat coagulation. Also, cold water lowers the temperature of the equipment. The second rinse with hot water and heating up again will consume a lot of heat energy, which is neither energy-saving nor difficult to clean because the milk fat solidifies and deposits on the surface of the equipment.
3. Cyclic cleaning time is too long
Cyclic cleaning time is not the longer the better, the general equipment can be mastered in 5 to 10 minutes. If the cleaning time is too long, the water temperature will drop below 40 ℃, which will cause the dirt to deposit on the surface of the equipment again. During the two milking intervals, the bacteria multiply in large quantities, increasing microbial content in milk. Large-scale equipment is CIP automatic cleaning, the time has been set, just press the open cleaning switch.
4. Insufficient dosage of cleaning agent
To save costs, some ranches should use few detergents. Especially when the water hardness is high, the amount of detergent should be increased accordingly. If the amount of detergent is not enough or the use of detergents is inferior, the microbial index will be increased and the quality of milk will be affected. Ranches should choose cleaners with a good reputation and good value for money. It is undesirable for the ranch to pursue cheap products blindly and ignore food safety.
5. Equipment issues
Lack of maintenance of equipment leads to deterioration of working performance. Long-term non-replacement of rubber components such as milk lining, milk tube, and sealing parts will result in serious air leakage and unstable vacuum of equipment, which is also one of the main causes of mastitis. The failure of surge amplifier, aging of cleaning bracket seal ring or missing parts lead to a large amount of sediment deposition in the pipeline, and serious scaling in the pipeline, especially in the upper part. Therefore, to ensure good cleaning, we must first ensure that the equipment is in a normal state.
II. How to achieve the best cleaning effect and ensure the quality of milk
Cleaning is an important part to ensure the quality of milk, never be sloppy. Standard cleaning procedures must be followed, reliable and well-known detergents selected, equipment cleaning system must operate normally, rubber parts and gaskets must be replaced regularly. The recommended procedures for ambient temperature cleaning are as follows:
To prevent the formation of a milk scale, the equipment and pipelines should be washed with warm water of 35-45 ℃ immediately after the equipment is used. Rinsing water can not be recycled and should be discharged directly. Do not pre-rinse with hot water. This denatures the protein and forms a protein film on the surface of the pipeline, but do not rinse it with cold water which will lead to oil crystallization, forming a layer of oil film on the surface of the pipeline.
2. Cyclic cleaning
According to the instructions and the amount of washing water, the dosage of the cleaning agent was determined, and the appropriate cleaning solution was prepared. Do not change the amount of cleaning agents at will. Ensure that the temperature of the cleaning water is within the required range (the temperature in the pipeline is 70-85℃, the return water temperature must not be lower than 40 ℃), and the time is 5-10 minutes.
After cleaning, rinse all parts of the pipeline and milking equipment with clean cold water (by the national drinking water standard) for about 5 minutes until the rinsing water is clean.
4. Sewage discharge
After washing, to prevent secondary pollution of clean equipment and pipelines, the system is completely emptied through the lowest port of equipment (such as opening the sewage valve at the bottom of the pump).
5. Selection of cleaning frequency
According to the hardness of cleaning water, the usage frequency of acid and alkali liquor is determined. The harder the water is, the more acid pickling times are required. To achieve the ideal cleaning effect, special detergent for milking machines must be used and the cleaning temperature, washing speed and cleaning time must be guaranteed.
6. A new method of low-temperature cleaning
If for some reason, the dairy farm can not meet the requirement of cleaning water temperature 75-85 ℃, a low-temperature cleaner can be considered, because the starting water temperature of low-temperature cleaner can be 45-55 ℃, and the discharge temperature after circulation can not be less than 30 ℃.