Concept of clean milk

      Concept of clean milk

Defination:

Clean Milk' is defined as milk drawn from the udder of healthy animals, which is collected in clean dry milking pails and free from extraneous matters like dust, dirt, flies, hay, manure etc.

Clean milk has a normal composition, possesses a natural milk flavour with low bacterial count and is safe for human consumption

Need for clean milk production :

—The objective of clean milk can be achieved by practical application of science based system such as Hazard Analysis Critical Control Point (HACCP).

—Not only it should produce quantum milk, but must also be free from debris, microbes and must remain so, till it is consumed.

— Raw milk quickly becomes sour when it is stored for long periods at high ambient temperatures prevalent in tropical and subtropical countries.

— This is because, the inherent lactic acid bacteria and contaminating microorganisms from milk vessels or the environment break down the lactose in milk to lactic acid.

—When sufficient lactic acid has accumulated, the milk becomes sour and coagulates.

— Raw milk that contains too much lactic acid, even if it does not appear to be curdled, will coagulate when heated. This acidity is known as “developed acidity” and such milk is not acceptable for sale.

Clean milk production in India:

—Village entrepreneurship is the main stay for bringing India as number one milk producer in the world.

—As a result there is limited scope for mechanizing milking procedures but does not mean that India cannot produce clean milk.

— By launching vigorous campaign, clean milk can be produced by good animal Husbandry practices in villages, small farms with the help of Dairy Development Boards, different Cooperative Dairy Federations etc.

Strategies for clean milk production:

—The first step to clean milk production should be education and training of milk producers on hygiene, housekeeping, sanitation, milking methods and good animal husbandry practices.

1.Awareness and training: 

2.Feeding practices:

3.Housing management:

4.Handling of milking vessels: 

5.Udder Hygiene:

6.Health management:

7.Milk collection and transportation: 

1. Awareness and training: 

—Educational aids and programmes should be organized for the farmers for making them aware of the importance of clean milk production.

—This should be in the form of charts/posters displayed at village, society and milk collection centres.

— Make them aware of the correct handling of the milk from udder to reception dock, maintenance of hygienic environment, clean utensils to availability of milk cooling bulk tanks and coolers

 2. Feeding practices:

—The feeds and fodder of the animals should not introduce directly or indirectly microbiological or chemical contaminants in the milk in amounts that is unacceptable to health.

— Feed fodder and silage should be procured from a reliable source and should be stored properly.

3. Housing management:

 — The shed should be comfortable and clean with suitable arrangement to dispose dung, urine, feed and fodder residues.

—There should be proper supply of clean drinking water and electricity.

—The shed should be washed before milking

Sanitation and Disinfection of the Animal Houses :

§Cleaning and sanitation are complementary. By sanitation we adopt hygienic measures aiming at creating conducive to health of animals and assuring product quality.

§The measures include proper cleaning of habituation, adequate drainage system, adequate lighting of building and sheds, proper ventilation and proper disinfection measures.

§It involves cleaning of bedding material like sawdust, paddy, straw etc. once daily

§Watering and feeding material to be thoroughly cleaned

§In case of mud floor, a top of 12-15 cm soil is removed and replaced with clean soil

§Cleaning and washing of milk parlors 

§Sloped drains having width of 6-12 inches and 2 inch depth. It should maintain a proper gradient of 1 in 60 for easy flow of drain water.

§Provide adequate lighting

§Provide proper ventilation

§Disinfect the houses by washing the houses with boiling water, flame blower or by using suitable disinfectants such as formaldehyde, phenols, cresols, washing soda, quick lime, bleaching powder etc.

§The hygiene and sanitation process practiced in a dairy herd can not only keep the animal and surrounding healthy but will also find its way for export of milk and milk products thereby, enhancing the efficiency of livestock and its productivity, survivability and longevity.

 4.Handling of milking vessels:

— The milking vessel should be made of stainless steel.

— It should be cleaned before and after milking with hot water and certified detergents/chemicals.

—It should have small mouth.

—The milker should wear clean clothes and maintain personal hygiene.

—He should wash his hands before milking and should not spit or smoke.

— Shaving the hair of the hind legs and tail should be carried out routinely.

—Also the fore milk should be discarded in a proper place.

5. Udder Hygiene:

—Effective milking practice is one important criterion in order to produce safe and suitable milk; failure of which may introduce contamination of milk. From an ethological perspective, the cow rests in a lying position, which inevitably leads to contact of the udder skin with filth on the bedding surface. As much as 1 x 1010 of total microorganisms can be found in one gram of filth from the udder surface.

—With unsuitable udder hygiene, the microorganisms present on the teat skin can contaminate the milk during milking or through the teat tip will penetrate the teat canal increasing the possibility of mastitis. Hence it is necessary to implement hygienic-prophylactic measures in maintaining cleanliness and udder health before and after milking of dairy herds, with the aid of disinfecting agents. 

—There are many procedures for udder hygiene prior to milking such as:

•     washing by spraying water and wiping of teats
•      washing of teats with a cloth immersed in warm disinfectant solution and drying with a dry cloth
•     immersing of teats in disinfectant and wiping with a paper cloth.

—Appropriate hygiene, such as dry cleaning, is necessary for lowering teat contamination whereas only the substantially soiled udders require washing with water. Therefore, if the udder is not substantially soiled, the teats should be immersed in active foam disinfectant and wiped with disposable paper cloths after 1-2 minutes.

—Disinfection prior to milking by immersing teats in a special cup, containing active foam based on surface active compounds, organic acids and hydrogen peroxide, and disinfection after milking by immersing teats in the agent containing 1.94% linear dodecyl-benzene sulphonic acid (LDBS) and skin care substances. 

—The implementation of udder hygiene after milking is a very rational method for maintaining acceptable udder health status, and is conducted by immersing teats in a disinfecting agent. This procedure removes the milk droplets that are left behind which can serve as a breeding ground for surrounding pathogenic microorganisms. Subsequent drying of the disinfectant creates a thin layer over the teat orifice, mechanically preventing the incursion of microorganisms through the teat canal.

—The benefits are manifested through a decrease in post secretory milk contamination, reduction of udder infections by so-called environmental microbes, and by a decrease in the number of subclinical mastitis.

—Nowadays, the priority in conducting udder hygiene is given to ecologically acceptable disinfecting agents that are not harmful to animals and the environment.

6.Health management: 

—Good animal husbandry practices including regular monitoring of disease such as mastitis should be a part of the routine work.

—During milking, using teat dips, and washing of udder should be an ongoing activity of the dairy farm.

—Sick animal shed should be far away from the milking barn and separated from the healthy ones.

— The healthy animals must be milked first. Improper use of veterinary drugs should be avoided.

7. Milk collection and transportation: 

—There should be a provision of bulk cooling tanks in order to reduce the bacteriological load in the milk immediately after collection.

—Introducing differential pricing system based on bacteriological quality of milk will help in overall improvement of milk quality reaching the dairy dock.

—Other prerequisites for clean milk production include hygienic norms, good animal husbandry practices and proper handling, storage and transportation of milk are important elements to produce quality milk.

—The lids of the milk cans should fit tightly preventing from entry of rain and dust.

—The cans should be stored in an inverted condition on stand.

—Excessive agitation while transportation should be avoided.

—When milk is agitated, the milk fat is destabilised which becomes easily oxidised.

— The milk tanker should have proper insulation.

— The number of spoilage bacteria in raw milk depends on the level of hygiene during milking and the cleanliness of the vessels used for storing and transporting the milk.

— During the first 2–3 hours after milking, raw milk is protected from spoilage by inherent natural antibacterial substances that inhibit the growth of spoilage bacteria.

—However, if the milk is not cooled, these antibacterial substances break down causing bacteria to multiply rapidly.

—Cooling milk to less than 10°C may prevent spoilage for up to three days.

—High storage temperatures result in faster microbial growth and hence faster milk spoilage.

Advantage

—Clean milk production is always beneficial/profitable for both the producers and the consumers because of the following reasons:

1. Safe for human consumption

2. Better keeping quality and chances of spoilage minimized

3. High commercial value

4. Renders protection against diseases like typhoid, dysentery, etc. which are transmitted to the milk through human contact

5. Helps to produce good quality dairy products or value added products

6. Transportation over long distance