Clean Milk Production improves Milk Quality and fetches more

Clean milk’ is the raw milk obtained from healthy Cows, under hygienic conditions . The milk should not contain any hazardous chemical including pesticides. It should not contain any harmful bacteria . The milk should be handled by healthy milk men in clean environment. The clean milk will have good keeping quality.

High quality milk fetches good price in market, reduce spoilage and can be stored for long time . Farmers can get good returns from milk if they ensure safe handling of raw milk by having in place a system at their farm that minimize contamination

Properties of clean milk:

· Usually comes from healthy milch animals.

· Should be devoid of bad flavours ,dirt and filth.

· Should contain relatively small number of bacteria

· Essentially free from diseases causing pathogens.

· Should have normal composition and acidity.

Purpose of clean milk production:

· To enhance consumer satisfaction

· Poor quality milk is difficult to handle for further processing to produce some value -added milk products.

· To prevent milk borne intoxications and zoonotic diseases.

· To enhance the Profit of the Producers

Sources of contamination of milk :

a) From inside the udder

· The animal by itself is one of the most significant contributors of microorganism in milk.

· Microorganisms enter the udder through duct at the teat tip.

· During progress of a milking, bacteria are present in the largest number at the beginning and gradually decrease. This is mainly due to mechanical dislodging of bacteria, particularly in teat canal where the number are probably highest. Discarding the first few streams of milk results in lower counts of microbes in milk.

· Most of the bacteria are excreted in fore - milk. When the animal is suffering from some disease, the causative organisms are also likely to come into milk depending upon the severity of infection.

· The most common disease in milch animal is mastitis and the primary causative organism; Streptococcus agalactiae is commonly present, even though no clinical evidence of mastitis is present in the cows. The other common mastitis causing organisms potentially harmful to humans are Staphylococcus aureus and Escherichia coli, occasionally Streptococcus uberis Streptococcus dysgalactiae. Some of the other organisms encountered occasionally are Listeria sps, Leptospira sp , Bacillus cereus, Pasteurella multocida, Clostridium perfringens, Actinomycetes, Coxiella burnetti and the Yeast Cryptococcus neoformans. The other organisms, which can come through the animal, include, Mycobacterium tuberculosis, Brucella abortus. etc .

How to prevent

· Animals should be maintained in clean dry environment free from dust and dirt.

· Milk from the first few stripping should be discarded.

· Milk from the infected udder should be discarded.

· Dairy animals should be periodically vaccinated against susceptible diseases.

b) From outside the udder

· Number and type of organisms associated with udder vary depending on type and amount of soil. Udder and teat become soiled with dung, mud, bedding material such as saw dust, straw etc. With heavily soiled udder teats the counts may be 1 lakh /ml.

· Udder micro flora is not affected very much by washing. Sodium hypochlorite washing and accompanied by drying help in reducing in number.

· Teat surface may also contain clostridia spores that are usually found in fodder, bedding & faeces.

How to prevent

· Prevent regular soiling of teat surface.

· Wash with disinfectant. Quaternary ammonium compounds can act effectively, but presence of organic matter interferes with action of Chlorine & it is also irritant to hands.

· Drying of teats before milking.

· Cloths

Milkmen and Clean Milk Production :

The milkmen should be healthy and undergo regular Health check-up. He should have his nails trimmed regularly. At the time of milking he should cover his head and wear mask. He should not cough and sneeze during milking.

Cleaning of Cow shed :

The shed should be cleaned off dung, left over feed and fodder particularly the silage and wet Brewer’s waste if they were fed. The mud floor should be sprinkled with water to make the dust to settle.

Care of Cows :

The cows should be bathed daily and groomed to remove loose hairs . The udder of cows should be examined for it’s health . The sick cows should be isolated from healthy cows.

Cleaning of Udder :

First wash the udder with plain water and wipe it well. Then clean with a disinfectant solution and wipe it off with another cloth. If the environment is very chill use luckwarm water .

Pre-dips :

· Iodophors (0.5 -1.0 %)

· Chlorhexidine (0.2%)

· Quats (0.5%)

After milking the teat should be dipped in teat dips to avoid infection through the possible milk drop around the teat opening.

During Milking:

Discard few strips of milk drawn from the teat as this part of milk will contain large number of micro organisms. The full hand milking be practised if manual milking is practised . The milking should be done as fast as possible.The milking should be completed with in 5- 7 minutes per cow.

Milking utensils :

· The improperly cleaned utensils are the main source of contamination in milk after it leaves the udder.

· The most hazardous situation arises when the milking utensils are not thoroughly cleaned after use and the milk solids with some moistures are left on the surfaces.

· These allow growth of microorganisms and heavily inoculate the fresh milk, which comes in contact with these utensils.

· When mastitis is prevalent in the herd, the utensils may contain Streptococcus agalactiae, Staphylococcus aureus, E. coli or Corynebacterium sp.

· When hot cleaning of equipment is done, the predominating organisms are thermoduric, mainly Bacillus sp. and Micrococcus.

· When cold cleaning is followed, heterogeneous microflora’s are present.

The milk storing utensils should be very clean . The steel utensils with narrow mouth and without dents, cracks and acute angles. The utensils should be cleaned before milking and after disposing . Following washing with ordinary water the utensils should be washed with warm water – containing a suitable detergent washing soda ( Sodium carbonate ) or Iodophor . Soap should not be used as it leaves a greasy film. After cleaning the vessel should be kept upside down for some time and drain the water completed. Then keep the vessel upright and dry it under Sun light .

Strain the milk :

After milking the milk should be strained using a filter and or clean white cloth. Straining is done to remove sediment and other foreign materials if any .If cloth is used for straining, it should be washed and dried daily otherwise dirty cloth will spoil the quality of milk .

Feeding - Feeding of the animals should be made an hour before milking. At the time of milking for the purpose of keeping milking cows busy, provide only concentrates which will be less dusty.

All containers with milk should have a lid on at all times .Milk should not be stored near the dung or feeding place. There are several reasons for this;

· Milk is sensitive to odours and may “pickup” dung or feed odours.

· Bacteria from dung or feed are more easily transferred to the milk if it is stored nearby

· Particles from the dung heap or the feed may contaminate the milk

· It should not be possible for animals such as dogs, cats and rats to approach the containers.

Post-milking guidelines :

· After milking the teats should be disinfected. This reduces, if not completely inhibits, bacterial growth on the teats.

· The teat canal stays open for a while after milking is completed, thus eliminating the important protection against entry of bacteria.

· The dip solution will both act as a physical hindrance for bacteria and as a disinfectant. Preferably the teat-dipping-solution should contain some lubricant in order to maintain teat condition and to prevent chapping and sores.Because the teat canal is open after milking, sometimes for as long as half an hour, the cows should be prevented from lying down.This can be done by giving enough feed to last for a long time after milking.

· All buckets, containers and machines used for milking must be cleaned both outwards and inwards immediately after usage.

· The towels used for cleaning and drying of the udder should be cleaned properly after each milking.

The dairy farmers should be provided with awareness training programme regarding the importance of clean milk production, sources of contamination of milk. So, that the farmers can get better benefit from dairy farming by preventing the spoilage of their product as well as by enhancing the consumer satisfaction

About the Author

Prof Dr M Murugan- Consultant, Animal Nutrition, Animeta AgriTech YourFarm . Former Dean, Tamil Nadu Veterinary and Animal Sciences University, Chennai. Animal Nutrition Specialist with 35+ years of experience in the field of Teaching, Research and Technology transfer to farming communities. His field of Research is Fodder production with special emphasis to Agroforestry systems and the class of livestock is small ruminant. Dr. M.Murugan has published 43 Research papers in both National and International Journals. He has also published 45 Popular articles ,authored 5 books and 2 manuals. His research articles are cited in several text books. He is the member of several Professional bodies like Indian Poultry Science Association Dairy Technology Society of India , Animal Nutrition Society of India and Tamil Nadu Veterinary Council.