By Ismail K. Tijjani 

The milk market in Uganda is awash with a variety of products from raw milk (street milk), pasteurised, and UHT- long lasting milk. There is confusion regarding the choice amongst these dairy products, which are vital for our daily nutrition.

The questions that pop into the minds of buyers are -is raw milk safe and clean for consumption, are there any preservatives in packaged milk, how is it that UHT milk stays intact at room temperature for months without going bad….?

You may have encountered one or more of these questions. There is a tremendous amount of disinformation about milk. Apart from the agricultural institutions, food sector, and academic institutions, some people who do not actually have any competence can find the audacity to comment on milk and dairy products in a very comfortable way! Yet it is very crucial to address these issues in terms of “food safety” other than making sweeping and unresearched statements to the consumer.

Is raw milk harmful?

Most of the raw milk sold is informal. In other words, it is not in any government control system like the DDA, etc. Some food-borne or animal-borne diseases such as brucella, listeriosis, tuberculosis, plague, cholera, and Q fever could be transmitted from animals to humans through milk that has not been properly heat-treated.

The fact that there are no harmful microorganisms found in the milk secreted from the milk glands of healthy animals does not warrant total safety. It’s more than likely that milk can be contaminated from the udder surface, ducts, teats, unclean milking environment, unhygienic materials, equipment used, and if raw milk is not cooled and stored in a short time after milking, microorganisms harmful to human health may be passed into milk or allowed to develop due to the time-lapse.

 When I say,” don't buy street milk."…

Many say, ‘I have never had any complaints and have been consuming raw milk for years”. Well, since you may not know the place where the person you buy the milk from feeds the animals, their animal’s health, milking technique, milking environment, equipment, storage area, milk cooling equipment (if any) are they in the gov’t control system or not, then the question is "Should your heart endure what your eyes do not see?”

It’s important to know that more than 100 types of microorganisms in dairy animals lead to many infections with mastitis being the most common animal disease (breast inflammation). Since one is not sure if the street milkman is not regulated for any standard by authorities, you might not know the hygiene standard of his products as well as the answers to these questions.

Only certified raw milk sales allowed

Bringing these concerns to light poses more questions. Whether the sale of raw milk (street milk) should be banned or not, could be food for thought and discussion for another forum. My clear advice is that the sale of raw milk should be done by certified agents. Thus, the Ministry of Agriculture should determine the procedures and principles for the supply of raw milk to the end consumer by local retailers. Accordingly, “only the sale of raw milk produced in a livestock enterprise that produces milk free from disease should be allowed.” In other words, “certified” raw milk sales with the ministry (DDA)-approved enterprises and outlets should be allowed. When we have milk that is under such strict control and ensures “food safety”, we will be asking ourselves “why not take raw milk?”

Is all milk processed as pasteurised or UHT Milk?

Before pasteurisation or UHT processes, pre-processes such as filter cleaning, bacterial, antibiotic, detergent test, acidity, freezing point, clarification, deaeration, separation, standardization of milk fat, homogenization are applied to raw milk. Some of these processes reduce the microbiological load of raw milk with the effectiveness of heat treatments. Considering the above landscape that seems impossible to be fulfilled by street milkmen, it would be ideal to opt for heat-treated milk.

What is pasteurised milk, how should it be stored and how many days should it be consumed?

Pasteurisation is a method of heat treatment to destroy all pathogenic microorganisms. It is aimed to destroy not all microorganisms, but only those that are pathogens. Pasteurization in milk is aimed at destroying the heat-resistant Mycobacterium tuberculosis, which leads to tuberculosis (tuberculosis) disease.

According to legal requirements; pasteurization in milk is defined as “applications involving a combination of high temperature short-time (HTST) applied to raw milk for 15 seconds at least 72 degrees, or low temperature long-time applied to raw milk for 30 minutes at least 63 degrees, or other time-temperature conditions that provide an equivalent effect”. The milk is then cooled to 4-5 degrees, stored, and dispatched.

Pasteurised milk should be kept in the refrigerator in its special packaging. Pasteurised milk lasts for 5-7 days only at refrigerator temperature. Pasteurized milk should also be kept in the refrigerator after opening the packaging and should be consumed within 2 days. 

What is UHT milk, how should it be stored and how many days should it be consumed?

The UHT (Ultra-high temperature) process is performed by heating the milk at 135-150 degrees in a very short time (2-6 seconds). In the UHT process, most of the spores forming microorganisms and all of the vegetative cells are destroyed, while enzymes become highly inactive. Thus, the milk becomes sterile and can be kept in its” special packaging “for 4-5 months at room temperature. UHT milk should be kept in the refrigerator after unpacking and consumed within 2 days.

The ability of UHT milk to be stored at room temperature is due to the properties of its packaging and the fact that the milk placed in it is sterile- microorganisms cease to be reactive. In other words, it can be kept at room temperature for months not because additives are used but because of the production, filling, and packaging method.

Is pasteurised and UHT milk low in nutritional value?

Heat treatment in pasteurized and UHT milk production is carried out under controlled conditions in such a way that the loss of nutritional value is minimal. Since raw milk cannot be consumed without boiling, what we should really compare should be food safety, not loss of nutritional value.

Uncontrolled boiling of Street milk at home for a long time (at least half an hour) causes a loss of color, taste, and nutritional value that is not comparable to pasteurized and UHT milk. Since pasteurized and UHT milk is heat-treated in a controlled manner so that it does not contain pathogenic microorganisms, you do not need to boil it before consumption.

Keep keen on health and scientific facts…!

The writer is a dairy expert