|Hygienic Milk Handling and Processing|
|Milk Processing Guide Series|
Training Programme for Small Scale Dairy Sector and Dairy Training Institute - Naivasha
|TABLE OF CONTENTS1. INTRODUCTION *
2. HYGIENIC MILK PRODUCTION AT THE FARM*
3. MILK TRANSPORT TO PROCESSING FACTORY*
3.1 Bulk milk transport.*
3.2 In-can milk transportation.*
4. DAIRY SANITATION AT THE FARM*
4.1 Proper sanitation of milk cans.*
4.2 Milking machines*
4.3 The cows*
4.4 Milk transport vessels (cans and tanks)*
5. HYGIENIC MILK HANDLING AT DAIRY FACTORIES*
5.1 General guidelines*
5.2 Cleaning and disinfections of plant and equipment.*
5.4 Hygienic Storage of finished products.*
5.5 Hygienic Transport*
5.6 Personnel Hygiene and Health.*
5.7 Laboratory Quality Control*
Good quality milk is essential for production of good quality dairy products, taste and flavour, free from pathogens and long keeping quality.
GOOD QUALITY DAIRY PRODUCTS CANNOT AND CAN NEVER BE MADE FROM POOR QUALITY RAW MILK
Good quality raw milk must be:
In order for milk to reach the processor and ultimately the consumer still in good condition, a number of things must be observed right from the farm level to the processing factory, and thereafter to the retailers and consumer. This booklet will highlight the essential steps that must be taken at each level in order to preserve natures best food- MILK.
2. HYGIENIC MILK PRODUCTION AT THE FARM
Whether milking by hand or machine, good hygiene is essential.
This requires that:
For small scale dairy farmers, setting up a milk cooling centre centrally may be the ideal solution.
Where farmers bring their milk to a cooling centre through a co-operative, they should do so as soon as milking is completed.
A Milk cooling centre with a capacity of 1000 - 3000 litres will serve up to 300 small holder farmers ensuring that the quality of their milk when produced under hygienic conditions is well preserved and accepted at the processing plant.
Fig. 1: A bulk (direct expansion) milk cooling tank (1000 - 3000 litres)
It is important to remember that under a hot environment milk will spoil within 3-4 hours. So any means of cooling that will lower the temperature of milk from 38° C at milking will help to prevent multiplication of bacteria. There are several options available.
In highland areas such as Kinangop, Limuru , Tiniboroa where the water temperature can be as low as 10° C, the milk may be cooled down to 2° C using water temperature by one of the following techniques.
Fig. 2. Milk cooling by immersion in a trough with cool water.
Fig. 3. In-can Rotary milk cooling.
Fig. 4 Surface milk cooler
In hot areas like in the coast, Western Province, North Eastern, Nyanza, cooling of milk blow 3-5° C below ambient temperature may be achieved through use of charcoal lined evaporative cooling cabinet.
Fig. 5 evaporative charcoal lined cooler
3. MILK TRANSPORT TO PROCESSING FACTORY
Milk cooled on the farm or cooling centre may be transported in milk cans or in bulk tankers. Bulk tankers are insulated, so the milk will remain cold until it reaches the plant (provided the transport is fast, i.e. short distance or good roads enabling milk to be delivered before the temperature of milk rises above 10° C).
Fig. 5. Milk collection by bulk tanker.
Alternatively, such milk may be filled in cans and transported in milk cans. This has, the advantage that a farmers can of POOR quality milk will not be mixed with other farmers GOOD quality milk and spoil the lot!.
Since the cans are not insulated, the transport to the factory must be efficient enough to enable milk reach the factory in acceptable condition.
Fig. 6. Milk transport in individual cans.
In the case of farmers delivering milk via pick-up (collection) points it is advisable that the milk cans are placed in a shaded area while awaiting pick-up by a milk transport vehicle.
Fig. 7. Provision of shade at pick up-points is important.
Bad milk will be rejected at the dairy plant. The farmer will lose money, the milk transporter may lose money if the fault is his. The nation will suffer because its people will not have the high quality food. To avoid all these bad things happening, hygienic milk handling is essential at each stage; at the FARM, COOLING CENTRE AND DURING TRANSPORT.
4. DAIRY SANITATION AT THE FARM
It is in the interest of every farmer and milk processor that the following are observed at the dairy farm
Immediately cans are emptied of milk they should be cleaned as follows:
Milking machines should be cleaned according to recommended
Timely replacement of worn out rubber parts should be undertaken regularly.
Follow proper milking hygiene; mastitis cows should be milked last and their milk discarded. Milk from cows treated with antibiotics should not be mixed with milk from healthy cows. Observe the required 4 day withdrawal period. Milk with antibiotics will affect consumers health as well as spoiling activity of lactic starter cultures used in cheese, yoghurt and Mala manufacture.
All milk transport vessels should be cleaned in the same way as outlined for milk cans above. There should be provision for water at milk cooling centres to enable ALL milk suppliers vessels or cans to be rinsed with cold water.
Fig. 8. Can washing at milk cooling centre or dairy plant is essential for hygienic milk handling.
5. HYGIENIC MILK HANDLING AT DAIRY FACTORIES
Disinfection of dairy equipment may be carried out by means of:
i) Packaging materials should be:
ii) Packaging should be carried out in away that:
Products should be stored in clean conditions at appropriate temperature and humidity to prevent deterioration or permit maturation ( e.g. cheese).
Products should be transported in clean vehicles under appropriate condition and be kept away from other goods.
Milk and other raw materials should be subjected as required to regular testing in order to ensure wholesomeness and freedom from pathogens.