AgriQuora . 20th Jul, 2021,
According to Dictionary.com, milk is "an opaque white or bluish-white liquid secreted by the mammary glands of female mammals, serving for the nourishment of their young."
Milk is a sterile product when secreted in the udder of a healthy cow (we’re talking about cow milk). It is loaded with nutrients, which makes it a fertile ground for microbial growth. Due to its susceptibility to microbial spoilage, there is need to adopt clean milk production principles to reduce chances of contamination.
Since more than 65% of all animal protein is directly linked to dairy products, it is important to ensure that consumers get only the best. To guarantee the best quality, there is need to consider the whole value chain. Clean milk production needs to start at the farm, before the farmer milks the product from the animal.
In this article, Olivia Solon suggests the possibility (and availability) of non dairy-derived milk and related products. The term milk has also been used to describe the substitutes used to produce non-dairy beverages that resemble the real product both in color and texture. Indeed, products such as soy-milk, rice-milk, coconut-milk, or even almond-milk have existed for years.
The availability of non-animal dairy substitutes solves the problems of methane gas production in dairy farms. Methane production is a major concern for the environment, as the animals produce lots of greenhouse gas that contributes to the greenhouse effect.
Again, the availability of dairy substitutes solves the ethical problems associated with dairy milk production. One can consume the dairy product without the guilt of knowing that a calf was sacrificed somewhere to enable milk production.
Humans learnt to domesticate animals from as early as about 9000 to 7000 BC. Cattle, goats, and sheep were among the first animals to be domesticated. People then learnt that they could exploit the animals for consumable products such as meat and milk.
Later on, the domesticated animals were used to produce other secondary resources such as hair, wool, skin, and also to provide labor in the farms.
Historians believe that domestication of animals originally began in Southwest Asia, from where the practice spread to other parts of the world. Some of the earliest Egyptian records show that the burn treatments consisted of using burn dressings of milk from lactating mothers (specifically mothers of male babies).
Dairy products were historically not a large part of the diet in many parts of the world over a long period. The reasoning for this could have been because the communities never kept animals as they relied on hunting and gathering, or they simply did not keep the dairy species.
Milk consumption became common in these regions comparatively recently, due to the European colonialism and political dominance over much of the world.
With the coming of the industrial revolution, urbanization sprung up and people started moving from the rural; areas to the urban centers. The rising populations in the urban centers created demand for food, and dairy products became very popular. In fact, in the Middle Ages, milk was referred to as the virtuous white liquor because alcoholic beverages were safer to consume than water.
The rising demand for dairy products resulted into increased production of the dairy products to meet the demand for the urban center dwellers. Some unscrupulous traders began to add water into the milk to meet the demands and increase their profits. This not only reduced the quality of the product, but also made it unsafe for human consumption.
The rising concerns for the quality and safety of dairy products necessitated standardization in the dairy industry. Consequently, a legislation in 1875 made it illegal to adulterate milk on any form.
Earlier on, Louis Pasteur had developed a method (pasteurization method) to kill pathogenic micro-organisms in food products to make them safe for human consumption. Packaging of properly pasteurized commercial grade milk to make the standard uniform and to reduce contamination of milk later followed.
Packaging assured consumers of quality and safety of the dairy products. These efforts paid off as consumption soon increased by over 90 percent.
By convention, all female mammals should be able to produce milk. However, there are special cases in which some of them are unable to produce. Humans do not produce it for commercial purposes.
There are milk-banks where the expressed commodity is stored and given to infants whose mothers cannot produce milk. This blog is specifically concerned with dairy milk.
FAO documents cow milk as the largest contributor to the commercial dairy products market.
In the West, commercialization of dairy production is very common. The system allows production of large volumes of high quality milk consistently to meet the high demands for the products. They have automated/semi-automated farms to reduce production costs and to maximize the economies of scale.
Their dairy cattle are pure breeds of high producers such as the Holstein. They have continually improved the cows for increased milk production. Holsteins consist about 90% of the dairy cows in the United States and 85% in Great Britain. Other high yielding dairy cows in the United States are Ayrshire, Jersey, Guernsey, Brown Swiss, and the Dairy Shorthorn.
In most developing countries, the dairy sector largely lies in the hands of the informal sector players. Subsistence farmers with one or two indigenous cows (producing <10 l/day) produce most of the milk.
The production is very low and is labor intensive. The animals walk long distances to the pastures and watering points. Tropical diseases are also a challenge for the farmers, limiting their capacity to produce more milk.
Luckily, the dairy sector has seen a very big boost in the recent past due to increasing demand for milk and interventions by non-governmental players. Farmers have realized the need to do dairy farming as a sustainable business.
Many farmers have adopted the high yielding exotic breeds that produce more hence increasing the farmer's income. There is ready market for the dairy products in most countries, making dairy farming a lucrative venture.
Aside from cattle; buffaloes, goats, sheep, camels, donkeys, horses, reindeer and yaks also produce milk. In fact, people have consumed their products and/or used them for making other dairy products.
Goats, sheep, and buffaloes are relatively high producers globally after cows. Goats milk has a close resemblance to human milk. It can be a better substitute for human milk.
As we have noted, you can only consider milk to be clean if it comes from a healthy cow. Therefore, every farmer must ensure that the animal is in proper shape health wise and provide clean feeds and water, in the right quantities and at the right time.
At the farm, the housing must be right to avoid introducing contaminants into the products. The milking equipment must be clean and the milkers must be in perfect health to avoid transmitting zoonotic diseases that may compromise quality of the product and safety of the consumers.
Understanding the concept is key to implementation of the principles of clean milk production.
Clean milk production is not only important for public health concerns but also for profit generation at the farm.
Before we delve into the actual principles, we should understand the kinds and sources of contaminants we’re dealing with. We can classify milk contamination into two broad categories: internal and external factors.
Here is a comprehensive list of the sources of contamination in milk. Clean milk production requires a holistic approach that will address animal health, dairy animal management, nutrition, hygiene, and ancillary equipment.
You should consider the following while implementing clean milk production systems at the farm.
There are measures at every stage that you should implement to ensure that you produce the best quality milk. You will be able to identify all the critical control points where you will put preventive measures to avoid contamination.
When you have a healthy cow, it secrets sterile milk in the udder. Contamination begins almost immediately when the milk leaves the udder through the teats as the contaminants get into the milk. Contamination, especially bacterial type, is inevitable. However, there is an acceptable limit for the contamination; a threshold within which the product is still considered safe.
The bacteria that gains entry into the milk will lead to deterioration in quality of the product and affect its suitability for processing into the finished products. For this reason, it is recommended that you pasteurize the milk to kill the spoilage bacteria. Pasteurization does not kill the spores, which can still germinate and cause spoilage in the dairy product.
Moreover, some bacteria will produce toxins, which are very stable and does not degrade during pasteurization. Any milk that has poison before pasteurization will still cause intoxication of the consumers.
It is important to ensure that the animals get proper nutrition and housing. The housing should shield the animals from the extreme weather.
Feeding is a central activity in dairy animal management. When designing the feeding schedule, ensure that the animals get adequate rest between feeding and milking (at least one hour). The animal feed should be clean and nutritionally sound with all the required nutrients in the right proportions and free from contamination.
During milking, keep the animal busy by providing concentrates.
If you are making your own feeds, ensure you have a balanced diet with all the required nutrients. Avoid products that have traces of contaminants such as pesticides, radionuclides, persistent pollutants, and toxins. Assess all feed additives and drugs you use to treat the cows to ensure they do not cause contamination. Follow manufacturer’s instruction and consult your vet.
Failure to assess all these items will lead to contamination of the dairy products, which can be catastrophic.
In any case, always observe the following points when managing a dairy animal for clean milk production:
The cow shed is a major source of contamination at the farm due to the presence of dust, mud, dung, and urine. The milking crush/stand needs to be clean because it is a primal source of contamination.
A properly designed cow shed will protect the cow from parasites and pathogens that come through contact. It keeps the unwanted people and animals out of reach and protects the cows from extreme weather.
Design the cow house to facilitate easy cleaning so that you can remove the dung and mud regularly. Water and urine should drain easily. When you keep the shed clean, well aerated and lit, even the flies will reduce since they love dirty places.
Clean the floors regularly and apply disinfectant. You can use one percent bleaching powder solution to prepare the disinfectant solution. Supply adequate amounts of clean potable water, which the cows will drink. You will also use the same source of clean water for cleaning the cow shed and the cows themselves, especially the flanks during milking.
Here are the handy tips for managing the cow shed:
As you are already aware now, the primary source of clean milk is a healthy animal. There is no way around it; you must just get it right. You should know how to detect the diseases and how to manage each. The best thing that will save you a lot of money is learning to prevent the diseases from ravaging your herd.
Conditions such as mastitis are very difficult to control once they enter your herd. This is because most cows that have the condition are still in the sub clinical stage of the disease. Learn to adopt vaccination and hygiene management for preventable diseases.
You can implement the following measures to promote clean milk production at the farm:
The Somatic Cell Count (SCC) is a very reliable indicator of milk quality. High SCC is due to the leukocytes (white blood cells) – which are released into the animal’s system as an immune response to an infection.
The most common trigger for high SCC is mastitis infection in cows, which alters the milk composition and reduces the milk yield. If untreated, mastitis can affect the lifetime productivity of a dairy animal. Mastitis milk has a characteristic low lactose, casein, butter fat and calcium but high immunoglobulins, somatic cells, pathogenic bacteria and sodium.
Injuries to the udder will lead to increased SCC since the animal’s immune system produces the leukocytes to intervene. To a great extent, the SCC count will indicate the level of hygiene maintained at the farm. Check the milk after every two weeks for the SCC index to ensure that your herd remains within the prescribed boundaries.
Essentially, SCC is the number of cells (leukocytes) per ml of milk. The boundaries are described as follows:
Manage hygiene at the farm and remove wastes such as dung and leftover feeds regularly. This will help you avoid breeding of pathogens that cause infections.
When one animal is infected, separate it from the rest of the herd and treat. Do not mix its milk with the rest of the bulk. Neither should you sell nor consume such milk.
Keep the sick animals clean and comfortable to facilitate rapid recovery and to avoid further spread of the infection.
There are very many equipment and utensils for handling milk at the farm. The milking machines, the piping system, bulking tanks, strainers, teat cups, milk churns and pails, etc, are all critical points of milk contamination at the farm.
Regular cleaning is necessary to avoid accumulation of dirt, which encourages bacterial growth. You must ensure that you conduct thorough cleaning with detergents at the right concentrations and temperatures to eliminate all pathogens.
Use CIP cleaning for the stationery equipment and pipe work. Ensure the detergent concentrations are right and provide enough temperature/contact time for effective cleaning.
Sanitize all surfaces that come into contact with milk after cleaning.
Hygiene is key to determining whether you produce clean milk or not. It transcends across all the stages we have discussed and is a central key in each. Every activity you do at the farm should be geared towards achieving high standards of hygiene.
There are critical points of contamination such as cow teats. Most bacteria take advantage of this window and fall into the milk during milking. The cow may also introduce the pathogens into the milk by dipping its tail or foot into the milk vessel during hand milking.
Dirty workers may also introduce pathogens into the milk. If the workers smoke, the milk will have a tobacco odor, which is not desirable. Similarly, workers should not wear perfumes at the odor will pass to the milk.
Ensuring adherence to high standards of hygiene will help you reduce contamination and produce clean safe milk.
The following are some measures you can implement to improve hygiene at the farm:
Bacteria replicates rapidly under warm temperatures. You must chill the milk to arrest bacterial activity and avoid spillage if you are not going to process the milk immediately.
Chilling will enhance the quality of milk before it reaches the dairy plant. You can achieve cooling through various means. The most obvious one is refrigeration. However, not every farmer has refrigeration facilities. In such cases, you can improvise a home-made charcoal cooler or use chilled water.
When you use the chilled water for cooling, immerse the milk churn into a larger container with water. Ensure that the level of water in the outer container is above the level of milk in the churn for an effective cooling. Change the water when its temperatures get warm (use your skin to feel).
Ensure you do not fully cover the top of the milk can to avoid off flavors from accumulating.
If you are selling to the dairy and they pick the milk from a designated place, ensure that the place has a shade to avoid direct sunlight.
After milking, bacterial contamination is the major cause of deterioration in quality. The sooner you arrest it, the better for you.
Here’s the recap of the cooling activities you can implement:
A dairy technologist is a food scientist who specializes in dairy products such as fresh milks, flavored milks, yogurts, ice creams, butter, and cheese.
From a single raw material, which is fresh milk, a dairy technologist can come up with many products that are differentiated to satisfy the needs of various market segments.
The ingenuity of manipulating this single raw material to obtain these products requires a great deal of acquired skill.
For this reason, anybody aspiring to be a furnished dairy technologist will need to have a satisfactory amount of training from a qualified institution to be certified for handling this delicate food product.
A dairy technologist will typically work in an office setting, a research laboratory, industrial floor, fieldwork, and/or universities and other higher learning institutions.
The profession calls for the technologist to work standard business/working days a week. However, there are some instances that will call for the technologist to put in long hours in the work, which will call for working overtime.
The profession of a dairy technologist offers good prospects for growth and the remuneration for the job ranges from average to above average.
A Dairy Technologist is a highly qualified individual who has undergone intensive training to be fully equipped to surmount the challenges of the industry.
To qualify for a dairy technology course, you must possess very high standards of academic and interpersonal skills. We will discuss some of the qualifications below to give you a glimpse of who a Dairy Technologist really is.
Any person who wishes to pursue a course in dairy technology needs to possess the following traits:
In this field, you are going to be working with people and they are going to need your prompt responses every time. Prompt communication is very necessary because you should already know that dairy is an extremely perishable product in raw form.
Your decisions are going to be fast and accurate all the time because the milk will not wait for you to make a decision when “you feel you have more time.” Your constant feedback on the progress of the assigned duties is going to determine if you are worth your salt.
In this profession, subtle things can turn out pretty serious. For instance, say you are procuring milk at a cooling center with a capacity of 10000 liters per day.
You have already received 8000 liters of clean high quality milk of resazurin test 6, and then you have a farmer walk in with a can of 50 liters of milk but the test result shows resazurin test 4.
On further interrogation, you find that the farmer mixed evening milk with morning milk in the same can that morning when delivering in to the cooling center.
Even though the quality of milk may be acceptable at resazurin test 4, you may end up compromising the quality of the whole 8000 liters of milk already procured if you are not careful enough with the 50 liters.
This is because bacteria multiply extremely fast even with a single degree increase in temperature. If you are not a detail-oriented person, you would not know that the farmer had mixed aged milk with fresh milk.
A dairy technologist must be a person who does not just do things haphazardly. You need to develop the culture of doing things systematically and methodically.
You will need to be a person who can derive a logical analysis of a situation and provide a systematic information that any rookie can understand and follow.
In every step of the way, you will need to keep beautifully organized notes to help track work progress. Organization will give you a window to evaluate the tasks.
It almost goes without saying that you have to be a dependable person. You are going to be dealing with food products consumed by the public.
If you are going to let your guard down on issues of quality, you are going to compromise the lives of the millions. You must protect your consumers at all costs.
You must be an incorruptible person who values the lives of people more than any other material gain.
You will be working alone on some projects in this profession. No one will be present to watch over you and push you to accomplish some tasks.
If you are the type to be pushed around, this profession is not for you. You will need to be highly motivated to accomplish some tasks because I can assure you that certain time; disappointments are going to be many.
In such moments, you will need to reassure yourself of your abilities because you will need reassurance quite a lot.
You will be frustrated many times in this profession. At such moments, patience will be the key to overcoming these temporary challenges.
Focus your mind on the big picture and work extremely hard to achieve your set goals.
One who aspires to be a good dairy technologist should have a strong background in biology (especially bacteriology), physics, mathematics, chemistry, economics, human resource management, psychology, and accounting.
You will be working with chemicals, electrical and electronic equipment, bacterial cultures, documentation, and you will have to work with a team.
Proper understanding of the chemical and biological aspects of various processes that you will be undertaking daily is crucial. You will also need to monitor and manage the progress of your project.
Once you have determined that you have these prerequisite backgrounds, start working towards getting your degree. Many higher institutions of learning offer a degree in dairy technology and related courses.
Obtaining a degree in this field will give you a voice and authority. You will get the necessary professional skills and knowledge to solve the problems in this industry.
You should note that you do not have to begin with pursuing a degree to become a dairy technologist. There are middle level colleges that specialize in dairy and offer certificate or artisan courses in dairy technology. You can start with these courses and work your way up to become a very reputable dairy technologist.
The advantage of working from the bottom is that you get a ton of exposure and experience along the way. This makes you properly equipped to handle the challenges of the industry better because you look at things from a practical perspective.
Opportunities for further studies are available for those who would wish to narrow down into dairy technology at graduate level and postgraduate level studies.
You may even curve out a career as a dairy scholar/researcher. These are some of the best paying jobs in the leading dairy research institutions and universities around the world.
As a dairy technologist, you will be conducting experiments repeatedly during the course of your work. It is important to ensure that you maintain a high level of consistency to obtain reproducible results.
Your patience will determine if you obtain reliable results. You should be able to obtain reliable results consistently to assure food safety.
Once you have earned a reputation for high standards of work ethics, you have even a harder job at maintaining the reputation high.
In order for you to have a sound professional standing, you may need to consider certification by a professional body.
In most countries, you will always find a professional body mandated with the responsibility of influencing the role of the contribution of Food Science and Technology to national development goals.
You may also join Veterinary Technicians and Technologists Association of your country. Besides giving you a rich networking resource, these associations will give you credentials that will set you ahead of your competition when showcasing your qualifications to a prospective employer.