Human is an exceptional mammal in consuming Milk
Mammals, they are the most advanced creatures on earth, they have mammary glands, which secrete white to yellow liquid, it nourishes their young ones when they suck the glands. This liquid is rich in proteins, fats and calcium and many other vitamins, we all recognise it as milk. Mammals nourish their young ones on their own milk in the initial stage of their life, but humans exceptionally consume milk for whole of their life: mother’s milk for 6 to 18 months and then milk of cow, buffalo and other cattles is used in daily diet almost till the death.
Milk and its different forms which human beings consume after lactating period is known as 'dairy products', milk is manipulated and transformed into varieties of taste, texture, flavor, and color.
Types Of Milk
Raw Milk is a colloid; many different procedures are performed on milk to handle different constituents of the liquid. Milk itself has several varieties in which they are available in market.
Raw Milk: It is the most pure form of milk available to consumers, if not heated or homogenized. Fat content of raw milk is around 3.9%, and many people think that raw milk has some more benefits above pasteurized milk, because some enzymes, vitamins and beneficial bacteria remain intact which are beneficial for our health and growth.
Pasteurized milk: in most developed and developing countries milk is to be pasteurized before selling it in the markets. This means that milk has to be treated with heat below boiling point so that harmful bacteria are killed; normally pasteurization is heating milk 72°C (161°F) for 15 seconds or 63° C (145° F) for 30 minutes.
Homogenized milk: When milk is allowed to stay still for some time fatty layer is formed on its top. Thus to prevent milk from separating into layers; milk is forcefully passed through micro holes with high pressure which breaks down fat globules and spreads them evenly in whole liquid, this process does not bring any nutritional change except it is more palatable and cream does not form on the surface.
Skimmed milk: To reduce the fat content of milk, creamy layer is trimmed down which decrease fat from 3.9% to 0.5%, this also reduce content of vitamin A because it is fat soluble vitamin.
Evaporated milk: As the name suggests most of the water from the milk is evaporated by heating and then viscous liquid is filled in cans for longer shelf life.
Condensed milk: condensed milk is similar to evaporated milk except it has high amount of sugar which acts as a preservative.
Full Cream Milk Nutrition
Procedures Upon Milk.
Other than pasturization, evaporation, homogenization and skimming other methods by which milk is operated and handled are:
coagulation of 'white portion' of milk, and water is left out.
After curdling of milk or 'high-speed spinning' of cream a watery substance is left out, which is strained out with the help of fine cotton cloth.
List of dairy products;
arranged in order of how they are acquired.
- Toned milk / Skimmed milk
Churning and straining
Churning, straining and evaporating
Curdling and straining
- Condensed milk
- Khoya, mawa
- Milk powder
For better understanding of all 'by-products' compare its nutritional contents with nutritional composition of whole milk.
Cream is the top most layer of the whole milk which is not homogenized, most of the fat globules in the milk aggregate and come on the top as fat is lighter than rest of the milk and form a creamy layer. When this layer is trimmed down from the milk remaining part is known as skimmed milk and the excluded fatty layer is called cream.
Cream Nutritional Content
Traditionally butter is made by churning milk cream by hands in pot; this process separates butterfat (fats present in milk) and buttermilk(watery milk). Butter consist of fats, little amount of milk protein and water. Most of the water is removed as buttermilk.
Butter can also be prepared in home, collect milk cream for several days and preserve it in freezer, and then churn it in electric mixer. Churning will form lumps of butter in liquid buttermilk which is to be strained to get pure butter.
Butter Nutritional Content
White watery liquid remaining after extracting butter from the cream is Buttermilk, so obviously it is low in fat and rich in protein.This left over liquid is also allowed to ferment by already existing bacteria to give it tangy taste. In India some spices(black pepper powder) and salt is added to give it good flavor and taste.
This drink in India is identified as chhas and sometimes chhas is also meant for spicy cultured buttermilk.
Making butter and buttermilk
Cultured Buttermilk (Lassi, Mattha)
When milk is fermented by bacteria to make it sour and tangy as in yogurt or curd, the cultured milk is then thinned by water to be consumed as beverage, the produced liquid is known as cultured buttermilk or lassi & mattha in Indian states. Cultured buttermilk is not in any case related to the buttermilk (by product of butter) .
Milk powder is nothing but solid remains of the milk, liquid milk is evaporated by roller or spray process and the solid remain is milk powder. It contains all the nutrition which whole milk has except water, vitamin C, vitjamin B12 and thiamin.
Powder of ‘skimmed milk’ is easily mixed in water while powder of ‘whole milk’ is difficult to mix because of its fat content.
Ghee (Clarified Butter)
Ghee is nothing but clarified butter, it’s made from butter or cream when water is evaporated by heating it and milk solids set down leaving above only liquid butterfat which is called ghee and it becomes solid at room temperature. Ghee does not contain any water or milk solids like butter.
Some diet conscious people would not like to include ghee in their meals but they should know that this ‘ghee’ made from pure milk is very healthy and essential for our body’s maintenance, specially the ghee made from cow’s milk is considered very healthy and many nutritionist suggest a spoon full of ghee daily for good and ‘disease free’ health.
Ghee (clarified butter) Nutritional Content
Yogurt (curd in India)
The carbohydrate of milk (lactose) is fermented and the acid thus produced is responsible for coagulation of casein protein and tangy taste. Coagulation of protein forces some of the water in the milk to the top which also contains some whey proteins and fermented carbohydrate. Mixing again the watery liquid in the yogurt solids helps in retaining the initial nutrition; otherwise some protein and carbohydrate are lost along with calcium and some other minerals.
Yogurt composition given is after removing whey portion.
Yogurt nutritional Content
Cheese is also made by the same mechanism of protein coagulation; however the coagulation is done in two separate ways, one by fermentation and other by enzymes or rennet. The process of coagulation decides the texture and flavor of cheese, cheese made by lactic acid coagulation (fermentation) is soft and tangy, and the cheese made by rennet coagulation is hard and sweet.
There are many coagulating agents like lemon juice, vinegar, rennet, lactic acid etc. All of them work at different temperatures and with different mechanism, the agent and temperature decides the quality of curd (coagulated casein protein) and whey (watery liquid protein separated from curd).
There are hundreds or different cheese flavors, texture and forms available in markets of different countries. Their properties and composition of nutrients are decided by Milk quality and process of pasteurization, skimming, fermentation, coagulation etc. Basic procedure of cheese making would be clear by reading below the curd (paneer) section.
Curd (Paneer in India)
Paneer is an Indian cheese and sometimes related to ‘Queso blanco’, the milk is heated and in hot milk vinegar or lime juice is mixed and stirred continuously until small lumps of curd are formed and then it is filtered in fine cotton cloth or coffee filter so the liquid whey is drained and semi solid curd remains in the cloth/filter. Then the curd is further pressed in cloth by different techniques so the remaining water is squeezed out and the curd becomes stiffer.
Unlike cheese paneer is eaten fresh without further aging and processing, moreover heating process in paneer also enable other than casein proteins like b-lactoglobulin to incorporate into the curd, this increases protein content of paneer.
Like buttermilk whey is liquid remnant of cheese & paneer. However whey is more watery, and not as much nutritious as butter milk, about all the fat and casein proteins are sealed in cheese and paneer; hence the whey consist of minerals, vitamins & some proteins,
It is also the condensed form of milk, the milk is heated and boiled until the milk becomes viscous liquid and then sugar, essence and dry fruits are added before serving.
we read in the beside passage that mawa contains all the ingredients except water present in whole milk. In fact mava cannot supply any of the said nutrients to our body except some traces of them.
read further to know more:
Khoa (mawa) can also be considered Indian-sub-continent version of condensed milk. Whole fat milk is heated until most of the water evaporates and the milk becomes sticky or dough like. So the nutritional value of khoya is similar to milk except the water content is reduced to 50%
An interesting and most important observation remains generally unsaid. The constituents of various milk produces mentioned above might give you an impression that these constituents present in them are useful for our bodies. What we don’t think is about readiness of our bodily processes to accept these constituents and also its manner of conveying these constituents to the parts of our body where they are needed.
Our digestive mechanism is unable to extract them from such condensed paste of milk like mawa. Almost all of it is washed away from our body intact as it was fed to it. Moreover in this sweeping cleansing process many other nutrients fed to our body through other diets too are washed away from our body! But again another observation remains unsaid. There are those, particularly in India, who have trained their digestive systems to extract useful nutrients from mawa. Bravo to them!
Viveksingh on June 18, 2020:
Ravindra desai on December 16, 2019:
All doubts are clear about all milk products thanks a lot
Marusa Romih from Slovenia on July 15, 2019:
Very nice article!
Umesh Chandra Bhatt from Kharghar, Navi Mumbai, India on February 09, 2019:
This is a very exhaustive article clearing all the doubts regarding milk and milk derivatives. Nice one.
anika thakur from New delhi on December 19, 2017:
anynomus. on October 09, 2016:
very informative, thank you very much.
Rose Jones on August 02, 2016:
This is really interesting. I appreciated the butter video, it was really funny- and all the Indian recipes.
Dipak on February 04, 2016:
Soumya on July 29, 2015:
Wow! What detailed information.. Thanks, many misconceptions were cleared.