0:14 So welcome everyone. Myself Miss CV Aishwara lecturer from the department of clinical nutrition. Sri Ramachandra faculty of allied health sciences. Sri Ramachandra Institute of Higher Education and Research deemed to be University Kur Chennai. So in this video let's talk about the milk and milk products. Before going onto this video we'll discuss about the objectives for today's session. At the end of the session, student will be able to explain the major components of milk, protein, fat, carbohydrate, vitamins and minerals and to evaluate its nutritional significance in the human diet. And to classify various types of processed
1:00 milk, including skimmed, toned, standardized homogenized and evaporated. and to describe pasteurization methods and their role in ensuring milk safety and shelf life. So the third objective is to outline the preparation of methods of common milk products such as curd, paneer, butter, ghee and cheese and to explain their functional roles in cooking and food preparation. So let's discuss about the basics how the milk and milk products have evolved. The story of milk goes back to the beginning of civilization itself. Cattle were domesticated even in prehistoric
1:45 times and milk was one of the most essential of all foods. Milk is one of the most complete single foods available in nature for health and promotion of growth. Milk is the normal secretion of mammary gland of mammals. Its purpose in nature is to provide good nourishment to the young of the species producing it. Man has learned the art of using milk and milk products as a food for his well-being and has increased the milk producing function of the animals best adapted as a source of milk for him. So the cow which is the most known
2:30 principal source of milk for human consumption in many parts of the world. Other animals as a source of milk for human beings are the buffalo, goat, sheep, camel and mar. In India more milk is obtained from the buffalo than the cow. some amount of goat milk is also consumed. Milk is a complex fluid containing protein fat carbohydrates vitamins and minerals. The main protein in milk is quin and it constitutes 3 to 3.5%age
3:16 of milk and the fat content of milk varies from 3.5%age in cow's milk to about 8% in buffalo's milk and it is said that lactose is the sugar present in milk. Fat is present in the form of fine globules varying in diameter from 1 to 10 micrometers. Milk also contains phospholipids and cholesterol. And the important minerals in milk are calcium, phosphorus, sodium and potassium. And milk is an excellent source of
4:01 riboflavin and a good source of vitamin A. However, milk is a poor source of iron with and also vitamin C which is ascorbic acid. The small amount of iron present is bioavailable. So let's discuss about the nutrative value of milk and milk products per 100 g through a tabular column. So basically they have taken four foods into consideration here. One is cow's milk, buffalo's milk, curd and paneer. Moving on to the energy perception, the paneer accounts up to the highest. The second highest will be the buffalo's milk. The
4:48 third highest is cow's milk and the fourth highest will be the curd. So the paneer which accounts up to 265 kilo calories of energy per 100 g and the second highest will be the buffalo's milk which is 117 kilo calalorie per 100 g and the cow's milk accounts up to 67 kilo calories per 100 g and the curd which is just 60 kiloalorie per 100 g. Moving on to the comparison of protein content among these four. It is said that Buffalo's milk has the highest amount of protein content where it sums up to 43 g of protein per 100 g. Whereas
5:35 the second highest will be the paneer which is 18.3 g of protein per 100 g. And the third highest is cow's milk where 3.2 g of protein per 100 g is present in cow's milk. And the last one will be the curd which is just 3.1 g of protein per 100 g. So here the highest sums up to the cow buffalo's milk. The next is about the fat. When it is discussed with the fats the nutrative value of milk and milk products of the of these are extremely varying. If you see the tableabler column here, the paneer is extremely the highest content of fat which sums up to 20.8
6:22 g per 100 g of fat is present in paneer. But whereas buffalo's milk have only 6.5 g of fat per 100 g. The cow's milk which is having 4.1 g of fat per 100 g and the curd have just only 4 g in the 100 g of curd. So let's move about to the calcium. When we are talking about the milk and milk products calcium plays a very important role in place where it is essential for the maintenance of bone, teeth etc. In that context if you could see buffalo milk has the highest amount of calcium which is 210 mg of calcium is
7:10 present in 100 g of buffalo's milk but whereas paneer has 28 mg of calcium in 100 g of paneer just a two decimal are being varied but whereas the curd has 149 mg of calcium per 100 g and the cow's milk content of calcium ium is just only 120 mg and as we discussed in the prior slides iron is very very negligible in terms of milk and milk products. If you could relate in the tabler column it is said that cow's milk buffalo's milk curd only 0.2 mg is present in all of these but whereas paneer iron content is not there. So
7:57 this is the summarization of the tabular column which shows the nutrative value of the commonly used milk and milk products. So let's discuss about the types of processed milk. There are very many types of processed milk which are available in the market like skimmed, toned, evaporated etc. But what are they actually? How are they made up of? What is the composition of this? All these criteria we will discuss it. Now the first one we will discuss about the skim milk, toned milk, standardized milk, homogenized milk and evaporated milk. So what is skim milk? So basically skim milk is whole milk from which fat
8:45 removed by a machine called cream separator. The quantity of fat is usually 0.05 05 to 0.1 percentage and it contains all other milk nutrients except vitamin A and vitamin D but it can be fortified with the help of the addition of the other vitamins. So this is the picture where you can see it is a cream separator machine where it helps in the making of skimmed milk. So the next will be the toned milk where toned milk is prepared by using milk reconstituted from skimmed milk powder and the skimmed milk is prepared by removing fat from
9:30 milk in a cream separator. So the next we have toned milk here. Skimmed milk is then mechanically dried to give skim milk powder. It is mixed with buffalo milk containing 7%age of fat. The fat content of toned milk should be around 3% only in terms of toned milk. The fourth is the standardized milk. In standardized milk, the fat content is maintained at 4.5%age and solids non-fat is just 8.5%age. It is prepared from a mixture of buffalo milk and the skimmed milk. So the next type of processed milk is about the homogenized milk. Nowadays in market
10:18 only homogenized milk is available and it is a mechanical process which reduces the size of the fat globules by forcing milk through small apertures under pressure and velocity. When milk is being homogenized the average size of the globule will be just around 2 micrometers. As you can as you can see in the picture that before homogenization the size of the globules is very high and after homogenization the size of the globules are very much reduced to 2 micrometers. So this is a basic comparison of the non-homogenized milk and the homogenized milk. So where the decrease in the size of the fat globules increases their
11:04 numbers and surface area the newly formed fat droplets brings about stabilization of the milk emulsion and this prevents the raising of the cream. Homogenized milk has a creamier texture, bland flavor and whiter in appearance. As you can see in the picture here, the right one is the homogenized milk and the left one is the non-homogenized milk. The non-homogenized milk, it doesn't have the uniform texture and it is not whiter in color. But in the homogenized milk, as you can see, it has some creamier texture in it and a kind of a whiter or very whiter in appearance when compared with the nonhomogenized
11:49 milk. So the last one will be the evaporated milk. It is made by evaporating more than half the water from a milk under vacuum at a temperature of 74°C to 77°C. It is then fortified with vitamin D homogenized and filled into canes. So nowadays evaporated milk is being more familiar in wide range of markets. Let's discuss about the technique called pasteurization. As we all know, milk is a favorable medium for bacterial growth. Pasteurization destroys all pathogenic bacteria including those causing typhoid, tuberculosis, dtheria as well
12:36 as yeast and molds. Pasteurization is a process which consists of heating milk to a certain temperature for a definite time to ensure destruction of harmful bacteria. And Louis pasture is the father of pasteurization. So let's discuss about the methods of pasteurization. There are basically three methods which is followed in all the industries to ensure appropriate pasteurization technique. The first method is holding method or batch process. Second method is high temperature short-term method or the continuous process which is called as HTST. And the last one is ultra high temperature method.
13:24 So moving on to the first one which is holding method or the batch process. So basically this is the commonly used one where the milk is subjected to 62.8° C for 30 minutes in order to get the milk pasteurized. This is the most commonly used method. The second method which is nothing but HD method which is high temperature shorttime method or continuous process where the milk is heated to 71.7°C and for not less than 15 seconds which is also commonly used in all the industries to make the milk pasteurized. The third one which is nothing but ultra
14:12 high temperature method where the milk is heated to a temperature of 93.4°C for 3 seconds. It is of a quite rare method but still these methods are being opted in the high infrastructural based industries. So basically the pasteurization in all the above mentioned the three methods. After heat treatment milk should be then rapidly cooled to prevent multiplication of surviving bacteria. During pasteurization the nutrative value of the milk will not be altered and at the same time it does not produce any unpleasant cooked flavor. harmful pathogens especially TB bacteria or
15:00 destroyed which is very harmful in nature and the most dreadful bacteria worldwide which is tuberculosis bacteria which is can be destroyed with the help of pasteurization and the shelf life of milk is increased due to a marked decrease in the total bacterial count which is the utmost advantage of pasteurization. Normally the shelf life of the milk and milk products is very very minimal because of the present of wide amount of bacteria. But once the milk is being pasteurized the total bacterial count will be drastically reduced and eventually the shelf life of the milk will be increased. So now we'll discuss about the various milk and milk products. As we are
15:48 talking about the milk, it is not only curd, you know, it is not only the ghee which comes from the milk. There are any number of food items which are prepared using milk as a premier medium. So we'll discuss all together. Now the first food product is kova where the kova is prepared by evaporating whole milk in an open cast iron pan with continuous stirring until it is semi-olid and it is used extensively in the preparation of Indian sweets. So basically when Indian sweets are being prepared the source of sweetener will be the ka. The next one is the cream. The whipping cream. Cream
16:34 is the fat of milk and used in the preparation of sweets. It is made by simmering large quantities of milk until a thick layer of milk fat and coagulated protein form on the surface. It can be consumed with or without the addition of sugar. So normally while making any of the bakery related food items this cream is playing a predominant role in the baking industry. So the next we have butter. So most people are very familiar with the butter. So butter is obtained by a technique called churning and when that cream so basically butter is obtained from the cream by the churning
17:20 technique. When cream is churned, the fat globules are destabilized and coaslays until the milk separates into two phases, the butter and the aque phase. Then the prepared butter is removed and washed thoroughly. So and also butter is used as a cooking medium in many many Indian recipes and it has been said to be one of the main ingredient in icing, cakes, biscuits and also in making of the breads. So therefore in the baking industry this butter is very much essential to have the fruitful outcome. So the next milk product is ghee. As many people are very
18:06 familiar, ghee is called as the butter oil. It is prepared by melting butter and separating the moisture from butter by heating technique. It is used in preparing. It is used in preparing most of the Indian sweets, savories, curries and variety rices like pula, biryani etc. Even in making of many of the sweets, pyasin, queseri, the ghee is the principal component used in that to have a good flavor. The next milk product is the paneer. As many people are familiar, paneer is basically the soft cheese prepared by addition of lemon juice or citric acid to hot milk and by
18:54 precipitating the quasin content and the liquid released in this process is known as the whey. The resultant curd is tied in a musclin cloth and hung for a day to squeeze any liquid present in it. And it is also said that the soft cheese that is obtained is used in the preparation of Indian gravies and also in the puls. And it is also known to have a very good source of protein as we saw in the last slide where protein content is very much familiar in the paneer. So paneer is such a very good source of protein for the people who prefer only vegetarian foods. So next we have the cheese here.
19:42 So basically cheese involves the curdling of milk with a enzyme called renitch under microbiologically controlled conditions. And milk is held at about 27° C in vats and a lactic acid culture is also being added. When the milk gets acidic, renet is added to it and the milk is then allowed to coagulate. So it is said that the curd formed is cut and heated to about 37° C with constant stirring to remove the whey. Weey is drained. Salt is mixed with the curd and it is pressed to
20:28 remove further amount of way present in it. And it is also stated that the cheese which is formed is coated with the paraffhin like substance to prevent loss of moisture because moisture should be prevented in the cheese. That's why the paraffin will be coated over there and the paraffin cheese is allowed to ripen for 3 to 6 months nearly at temperatures between 45 to 60° C. And cheese is also a very concentrated source of protein unlike paneer. Cheese also has protein but not to the highest extent when compared with the paneer. So the next we have curd here. So curd is
21:16 prepared by heating milk to about 50°C. A teaspoon of curd which is more or like a starter from an earlier batch is added and then it is mixed thoroughly. The lactic acid bacteria which is present in the starter curdles the new formation of the milk. So the bacteria breaks down lactose to lactic acid thereby increasing the acidity of milk. When the pH level reaches to 4.6 the milk protein quin coagulates as the final yield product called curd. And the optimum temperature for the formation of curd is just 35 to 40°C.
22:03 And the time needed for curd formation is 8 to 12 hours depending on the atmospheric temperature. Curd is used as a dressing on salads made from fresh vegetables and combines well with the plain cooked rice. And it is also stated that curd is the richest source of calcium. So thereby it can helps to have good bones and also the teeth health. So let's discuss about the yogurt here. This is a coagulated milk product with curdlike consistency and it is made from partially skimmed or whole milk and it has a slightly acidic flavor
22:49 and it is being stated that in the production of yogurt a mixed culture of three bacterias is added. So the appearance-wise curd and yogurt looks similar but the probiotics present in it it varies. In the yogurt there are three mixed culture of bacteria is present. Number one lactobasilus bulgaricus. Number two streptococcaucus thermopilus and number three is lactobasilus acidophilus. So these three are the bacterial culture which is added to pasteurized milk and incubated at 42°C to 46° C to have the final yield product as
23:36 yogurt. So let's discuss about the role of milk and milk products in cookery. So do you think that it actually plays a role in the cookery means the answer is a big yes because nowadays milk is the actual start or actual product in the preparation of many foods especially the milk contributes to the rich nutritive value of the diet. For example when the preparation of milkshakes, plain milk, flavored milk, cheese toast etc. where the milk has a predominant role to play and it is also said that for the preparation of pyasm tea coffee the milk
24:25 adds a very rich taste and a very good flavor. So thereby milk is extensively being used in the cookery and for the preparation of white sauce or the cream soups milk acts as a thickening agent along with the starch thereby which plays a significant role in making Indian foods. So cream soups or the white sauce are the very good examples for the milk usage in the cookery. The next is milk is also used in the preparation of deserts. Example, in the preparation of ice cream, also in the preparation of puddings. As you can see in the picture, the nice texture or the nice appearance is got only with the
25:13 help of the milk. At the same time, milk adds a very rich flavor. That's why in almost all the deserts, the milk is being used. So the next is the milk or buttermilk is used as a levening agent and to improve the texture while making dla. DLA is also a famous food product from the north side where some amount of curd or buttermilk is used there in order to have that fluffy uh fluffy texture thereby it acts as a levering agent. So the next is on the marinating agent as well. So especially when making biryani or when making any sort of kebabs curd can be added to
25:59 marinate chicken and meat so that the taste will be enhanced and also the crispiness is tends to occur. Curd is also used as a soaring agent. This is a very uh good term where I could say where in the preparation of dry curd chilies and while making rava dosa the sword curd will be added to have the good taste. Thereby in kitchen curd plays a very major role. And also for making quesery or the carrot halva, the beetroot halva, the kova can be kova which is a yield from the open iron cast pan which has been obtained from the milk which can be
26:46 added as a binding agent in preparation of carrot halva etc. thereby having a very good texture and also cheese. Cheese is one of the byproduct of the milk where it can be added as a garnishing agent. So like the shredded cheese can be made or added in all the food products to have the good taste and the buttermilk which is the very best therapy the cost expense I mean the cost inexpensive to suit for the summer where the salted buttermilk is used for quenching the thirst of many people. So the key takeaways is that milk and milk products like curd, paneer, cheese,
27:33 butter are extremely rich in calcium, high quality protein, vitamin B12 and riboflavin which is nothing but vitamin B2. So basically when we call about the term milk and milk products they are essential for the good bone and also for the teeth health and it has been stated that milk is a complete food but actually low in iron. As we discussed in the previous slides only many of the milk and milk products the iron content is negligible. So stating 0.2 2 mg of iron is present in 100 g of you know probably the curd buffalo's milk and cow's milk that's why milk is called to
28:18 be the poor source of iron and also the poor source of vitamin C which is ascorbic acid and it it is also fortified when these iron and vitamin C fortification is where people adding the nutrients intentionally to overcome the deficiency so when we fortify Why these milk with good quality of iron and vitamin C definitely it will helps us to address the deficiencies and it is also that the different types of processed milk such as skimmed milk, toned milk, standardized milk, homogenized milk and evaporated milk and also much more are available in the market on the day-to-day basis. So people can utilize this and they can be
29:06 benefited out of this. And pasteurization is a technique where it happens in milk and it destroys all pathogenic bacteria and increases the shelf life of the milk. Basically milk and milk products are easily prone to uh bacterial invasion. So by that it can it has the tendency to spoil easily but when when we apply the pasteurization technique so it destroys all the pathogenic bacteria so that the shelf life of the milk can be increased. So this is all about the milk and milk products. Thank you.
