The importance of milk for a healthy body

7/29/2019 The importance of milk for a healthy body

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TRANSILVANIA UNIVERSITY OF BRASOVFACULTY OF ECONOMIC SCIENCES AND BUSINESS ADMINISTRATION

The importance of milk for ahealthy body

Comparison between raw milk and powdered milk

Dobrin Marian

Fodor Andreea Nicoleta

BA 8801

3rd Year


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Table of Contents

Table of Contents ................................................................................................... 3

Introduction .......................................................................................................... 4

Fundamentals of Dairy Chemistry , Robert Jenness, Elmer H. Marth, Noble P.

Wong, Mark Keeney, AN Aspen Publication .......................................................... 4

History of milk ........................................................................................................ 5

History of powdered milk .................................................................................... 5

Characteristics of raw milk .................................................................................... 6

4. Characteristics of powdered milk ....................................................................... 8

Disadvantages of Powdered Milk ........................................................................ 9

5. Comparison between fresh milk and powdered milk .......................................10

6. Nutritional facts ............................................................................................... 11

7. Conclusions ..................................................................................................... 13

8. References ...................................................................................................... 15

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The importance of milk for a healthy body:comparison between fresh milk andpowdered milk

Introduction

Milk is secreted by all species of mammals to supply nutrition and immunological

protection to the young. It performs these functions with a large array of distinctive

compounds.1 Interspecies differences in the quantitative composition of milk reflect

differences in the metabolic process of the lactating mother and in the nutritive requirements

of the suckling young. The milks of certain domesticated animals, and dairy products

therefore, are major components of the human diet in many parts of the world. Domesticated

goats, sheep and cattle have been used for milk production since about 8000 BC. Milk is a

very complex fluid containing several hundred molecular species. The principal constituents

are water, lipids, sugar (lactose) and proteins. In addition, there are numerous minorconstituents , mostly at trace levels, e.g. minerals, vitamins, hormones, enzymes, and

miscellaneous compounds. The chemistry of these compounds is generally similar across

species but in many cases their structure differs in detail.

Because it is an unstable foodstuff, prone in particular to microbiological degradation, it

requires storage to smooth out supply. The production of milk powders and other dried milk-

protein-containing products has been the method of choice for over 100 years for the storage

and shipping of milk over long distances and/or time as it confers stability and massively

reduces weight and bulk. Milk powders were known to the Chinese and were described by

Marco Polo. The production of milk powders was described by Nicolas Appert in the early

nineteenth century and commercial processes for the spray drying of milk were patented in

1 Fundamentals of Dairy Chemistry , Robert Jenness, Elmer H. Marth, Noble P.Wong, Mark Keeney, AN Aspen Publication

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the USA in 1872 and 1905. This opened the way for large scale industrial production of milk

powders throughout the twentieth century.

History of milkAround 10 000 BC, the agricultural revolution occurred changing societies from

nomadic tribes to those who settled in communities. With this came domesticated animals

and the ingenuity for people to use by-products such as milk.

In ancient Egypt, milk and other dairy products were reserved for royalty, priests and the very

wealthy.

By the 5th century AD, cows and sheep in Europe were prized for their milk. By the

14th century, cows milk became more popular than sheeps milk. European dairy cows werebrought to North America in the early 1600s.

Louis Pasteur, a French microbiologist, conducted the first pasteurization tests in 1862.

Pasteur is credited with revolutionizing the safety of milk and, in turn, the ability to store and

distribute milk well beyond the farm. Commercial pasteurization machines were introduced

in 1895. In 1884, the first milk bottle was invented in New York state. In the 1930s, milk

cans were replaced with large on-farm storage tanks, and plastic coated paper milk cartons

were invented, which allowed for wider distribution of fresh milk.

History of powdered milk

During ancient times, the warriors of Kidans carried powdered milk products for use as

military provisions. Tribes such as Khalha, Buriad and other western Mongol used cows

milk to make aragoul or dried pellets.

The technologies used to make condensed milk and evaporated milk were applied in the

early twentieth century to the production of dried milk powder.

Nicholas Appert, produced dried tablets in 1810. A patent for a dried milk process with

sugar added was issued to a man name Birdeye in 1850 and in 1855 a British patent covering

a milk drying process with issued to Grimwade and a number of other patent were issued.

In 1869, Henry Nestle perfected the process in Switzerland.2

United States issued a patent for producing it in 1872. In 1899, Dr. Martin Eckenberg, of

Sweden, developed a film drier operating in a vacuum.

In United Kingdom, sterile powder milk successfully marketed after 1900, when new

technological process permitted large-scale manufacturing, it was first bought by a2 http://www.beveragehistory.com/2012/01/history-of-dried-milk.html

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managerial, professional and artisanal segments of British society.

By 1907, the local milk stations began to distribute it in place of liquid milk, so that its use

spread to the poorer workers. In United States in 1895, candymaker Milton Hershey crated

milk chocolate formula based on Swiss method of combining conched chocolate with

powdered milk.

Whole and skim milk powders are commercially produced currently by spray-drying.

Whole or skim milk is dispersed as fine droplets into stream of hot air and the bulk of the

water evaporates in a matter of second. By 1980s imported dried milk became a significant

competitor in developing countries for people who lacked refrigeration.

Characteristics of raw milkAs young mammals are born at different stages of maturity and with different nutritional

requirements, the milk of each species is designed to meet the requirement of the neonate of

that species. Milk is intended to be consumed unchanged by the young suckling its mother.

However, man has consumed the milk of other species for at least 8000 years. 3 Several

species have been used for milk production but today cattle is the principal dairying species

accounting for almost 85% of total milk production. Milk is often described as the most

nearly perfect food. Many of the minor constituents of milk have biological properties.

However milk is very susceptible to the growth of microorganisms which will cause spoilage

if the milk is stored. To counteract this, man has developed a range of products that are more

stable than milk. Some of these date from 4000 BC and have evolved desirable epicurean

characteristics, in addition to their nutritional value.

3.1 List of different types of milk

Cows milk remains the most popular type, because it is slightly sweet, mild and

subtle in flavor. Most of it comes from Friesian cows, but milk from Jersey and Guernsey

cattle is also available.

4Pasteurized - most of the milk in stores has been pasteurized. This means that it has

been heated to a temperature that eradicates any potentially dangerous bacteria, but does not

affect the flavor of the milk.

3 An historical, scientific and practical essay on milk as an article of human sustenance with a

consideration of the effects consequent upon the present unnatural methods of producing it for thesupply of large cities , by Robert M. Hartley , New York4 http://mmdelrosario.hubpages.com/hub/different-types-of-milk

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Pasteurized milk will keep fresh for 2-3 days in a fridge. This is the kind of milk most often

used for drinking, on cereals and in cooking.

Unpasteurized - also known as raw or untreated milk, is becoming increasingly

available as people acquired a taste for untreated products. Herds used to provide untreated

milk must always be certified. This involves the farms being stringently tested to ensure no

dangerous bacteria are present.

It is recommended that babies, young children, the elderly, pregnant women and

anyone with an impaired immune system should avoid drinking unpasteurized milk.

Semi-Skimmed and skimmed milk

This is milk from which part or almost all the fat has been removed.

Semi-skimmed (low-fat) milk has a fat content of 1.5 -1.8 per cent and skimmed

milk has a maximum fat content of 0.3 per cent although 0.1 per cent is more usual.

Skimmed milkcontains half the calories of full-cream milk and only a fraction of the

fat, but nutritionally it is virtually on a par, retaining most of its vitamins, calcium and other

materials. However, removing almost all the fat also removes the fat-soluble vitamins A and

D. As a result, skimmed milk is not suitable for young children. Fortified skimmed milk with

added vitamins and calcium is available.

Homogenized milk

When milk is homogenized the fat particles are broken up and dispersed evenly throughout it.

The cream is blended into all of the milk, instead of floating to the surface, which it does

when it is left to its own devices. Homogenized milk has a richer flavor that is not to

everyones taste.

Long-life and UHT milk

Long - life -milk labeled as long-life has been pasteurized,

homogenized and then kept at a high temperature for long enough to

destroy bacteria. The process gives the milk a rather odd burnt caramel

flavour, but is nevertheless a useful stand-by as it will keep unopened

for at least a week. However, once it has been opened, keep it in the refrigerator and treat asyou would a normal milk.

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UHT( ultra-heat treatment) milk will keep, unopened, for even longer than long-life

milk. This milk has been heated briefly to a high temperature (1320C / 2700F). Although the

taste is affected, it does not have quite the same caramelized flavor as long-life or sterilized

milk. Unopened UHT milk can be stored, without refrigeration for up to three months. Once

opened store in the refrigerator and treat it as fresh milk.

4. Characteristics of powdered milk

5Powdered milk is less expensive than fresh milk and it is relatively non-

perishable. And in terms of nutrients like calcium and protein, dried milk is comparable to

fresh milk. Due to its shelf-stability, powdered milk is often used in disaster areas and by

survivalists and hikers. It is also easier to transport than liquid milk and can be reconstitutedinto a liquid quickly. Milk powder is usually much cheaper than liquid milk, since it only

takes about five cups of milk powder and about 15 cups of water to make a gallon of liquid

milk.

When buying powdered milk, it is important to note that there are different grades of

milk powder, as both nutrition quality and flavor can vary depending on the grade. For

example, some powdered milks have extra amounts of Vitamin D and Vitamin A added. A

"US Extra Grade" label or stamp on a powdered milk product means that the product is made

to dissolve instantly when added to water and is manufactured to have a sweet, pleasant taste.

It is also important not to confuse powdered milk with evaporated milk or condensed

milk. While powdered milk is completely dry, evaporated milk still has about a 40 percent

water content. Though evaporated milk is shelf-stable like powdered milk, it is darker and

usually comes in cans. Condensed milk is a thick dairy product made of sweetened

evaporated milk, and is often used in making desserts.

If one researches on the Internet, he will quickly come across a lot of sources who

claim that powdered milk is extremely bad for him because it contains oxidized cholesterol,

which is supposedly the most dangerous type of cholesterol. They also claim that powdered

milk is added to all lowfat and fat-free milk in order to give it more body. And they say that

there is no way for one to tell whether or not milk contains added dry milk because the

packagers are not required to list powdered milk in the ingredient list. Potential dangers of

powdered milk are the following:

5 http://local.ug/forum/Thread-Is-Powered-Milk-Bad-For-You

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It is true that in the process of turning fresh milk into a powder, the cholesterol in the

milk is likely to get oxidized. And it is true that oxidized cholesterol appears to be a

particularly dangerous form of cholesterol of all.

Oxidized cholesterol is cholesterol that has been sort of roughed up around the edges,

which makes it particularly irritating to the blood vessels. That irritation is what triggers the

formation of plaques, which are the beginning of heart disease. What is worse, oxidized

cholesterol molecules can in turn oxidize other cholesterol molecules, setting off a sort of

chain reaction.

Disadvantages of Powdered Milk6

Appeal

The flavor and consistency of powdered milk is slightly different than that of regular

liquid milk. Adding that to the absence of aroma molecules, powdered milk is usually less

appealing than regular liquid milk, especially if that is what you are accustomed to drinking.

Powdered milk is sometimes mixed with regular liquid milk, a little bit of sugar and vanilla,

or chocolate to assist in masking the taste. Many times powdered milk is made from nonfat or

low-fat milk, and the lack of fat also affects the flavor.

Value

In the past it was more economical to buy powdered milk than regular liquid milk. But

with inflation and other economic changes that have arisen, both milk products are now

generally the same cost. Powdered milk can be purchased in bulk, but the cost is still fairly

high, and then you have the issue of the proper storage of an abundance of powdered milk.

When purchasing from a store or bulk foods distributor, be sure to check for freshness. Any

human error in storage can result in a bad batch of milk, especially if it has been sitting on

store shelves for a while.

Storage

Regular powdered milk must be mixed ahead and stored in the refrigerator. Instant

powdered milk may be mixed and used immediately. Once mixed, the milk will keep for five

to seven days in the refrigerator, just like regular liquid milk. Unfortunately, there is a

6 http://www.ehow.com/list_6682612_disadvantages-powdered-milk_.html

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misperception that powdered milk in its powdered state has an indefinite shelf life. Nonfat

powdered milk has a longer shelf life than regular powdered milk because it does not contain

fat, which can go rancid. Powdered milk should be stored in its original container in a cool,

dark cupboard at temperatures no higher than 70 degrees Fahrenheit. Many homes exceed

this temperature during summer months, which compromises the integrity of the powdered

milk. Unopened packages of nonfat dry milk can be stored for up to a year. Once opened,

they should be used within a few months for best flavor and nutrition, but they are still safe

and nutritious for up to a year.

5. Comparison between fresh milk and powdered milk

The two production processes are different. Fresh milk production does not onlyconsist in pumping the pasteurised and homogenized fresh milk into bottles and trucking it to

the stores. It is more complicated, for skim, low-fat and reduced fat milk. Firstly the whole

milk is centrifuged and separated into it's components, namely skim milk and the solids

(butterfat, protein, minerals etc). 7The skim milk then has solids (i.e. fat) added back into it in

set proportions depending on the final product - 1% fat or 2% fat etc. This provides for

consistent milk products, as the solids content differs between cows and within seasons

apparently. The fat that is added back into the milk for low-fat and reduced-fat milk is

normally in the form of dried skim milk powder (It helps give the milk a nicer consistency for

consumers). It is then heat treated and homogenized before packaging and transport.

Dried powder milk goes through the same clarification and separation process as fresh milk,

then it has fat added back for whole milk powder and it's homogenized. The milk is heated to

evaporate some of the water content, and then sprayed into a hot chamber where the droplets

dry and are collected, packaged etc. Lecithin is usually added at some stage too, it coats the

powdered droplets and helps it dissolve in cold water.

Obviously however, dried milk had several advantages over fresh: It can be stored for

much longer and doesn't require expensive refrigeration;

The mass and volume of the final product is much smaller than fresh so more product can be

stored and transported in the same space;

Supply and demand - there is a much higher global demand for powdered milk. The

first two points indicate big savings, both for the manufacturer and the retailer.

The third point relates primarily to the demand for dried milk by the food industry. Milk goes

7 http://www.towards-sustainability.com/2007/01/powdered-vs-fresh-milk.html

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into a large array of foods humans eat, particularly bread, biscuits and cakes. There is also a

huge demand for dried milk in many countries that do not have the facilities (or fuel/ energy)

to transport and store fresh milk, especially many developing countries. Dried milk is also the

major component of infant formula, used world-wide. Whey powder is also a major protein

additive in processed foods. Using dried milk is not without some controversy though - there

are many internet sites claiming that the high heat used in the drying process oxidises the

cholesterol in the milk (they become "oxysterols") and the amino acids are denatured and

become neurotoxins.

6. Nutritional facts

Calories - measure amounts of energy 1000 times greater than the units in scientificcontexts

Nutritional information for dry milk is based on mixing 1/3 cup powder with 8 oz. of

water to make a full cup of milk. A cup of non-fat dry milk contains 82 calories, while a 1-

cup serving of liquid non-fat milk contains 90 calories per serving. Among other liquid types,

whole milk contains 149 calories, 2 percent has 121 calories and 1 percent has 104 calories

per 1-cup serving.

Fat - wide group of compounds that are generally soluble in organic solvents and

generally insoluble in water.

Fat amounts contained in both dry and liquid milk also differ. In a 1-cup serving of

nonfat liquid milk, there's 0.5 g of fat. Whole milk has 7.7 g of fat, 2 percent contains 4.4 g

and 1 percent contains 2.2 g of fat per serving. In a 1-cup mixed serving of dry milk, there are

0.17 g of fat per serving.

Vitamins - organic compound required by an organism as a vital nutrient in limited

amounts

The amount of calcium in dry milk is a bit lower than liquid, with 283 mg per 1 cup

mixed serving. A 1-cup serving of nonfat liquid milk contains 316 mg, while whole milk has

291 mg; 2 percent has 296 and 1 percent contains 312 mg of calcium. Dry and fresh milk are

equally rich in many other nutrients such as protein, potassium, vitamins A, B12, riboflavin,

niacin and phosphorus.

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Proteins8 - large biological molecules consisting of one or more chains of amino

acids.

The proteins of milk fall into several classes of polypeptide chains. One groupd, called

caseins consists of four kinds of polypeptides. Almost all of the caseins are associated with

calcium and phosphate in micelles. The other milk proteins called whey proteins are a

diverse group including -lactogobulin, blood serum albumin, and immunoglobulins.

When compared to other protein supplements, dry milk powder isn't an effective choice

because it is relatively low in protein. Each 1/3-cup serving of dry milk powder contains 8 g

of protein, which is much less than the 23 g that one scoop of whey protein provides.

Carbohydrates - organic compound that consists only of carbon, hydrogen, and

oxygen, usually with a hydrogen:oxygen atom ratio of 2:1; in other words, with the empirical

formula Cm(H2O)n.

In bovine milk, and indeed in all milk consumed by humans, the overwhelming

carbohydrate is lactose. Carbohydrates in milk other than lactose include monosaccharides,

neutral and acid oligosaccharides, and glycosyl groups bound to proteins and lipids.

Storage and Loss of Nutrients

Refrigeration of fresh milk is necessary to prevent spoilage. Shelf life is typically afew weeks and is the same for powdered milk that has been mixed with water. However, with

unmixed dry milk, the shelf life can last much longer than that of liquid milk as long as it's

sealed and stored in a cool, dry place. Once opened, use it within 3 to 5 days or it'll become

lumpy. If not used shortly after opening, the flavor also may change and nutritional values

may decrease.

8Milk Proteins: From Expression to Food, by Abby Thompson, Mike Boland, Harjinder

Singh, B.S

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Raw milk Powdered milk

Raw milk Powdered milk

Storage

Price

Proteins

Vitamins

Fat

Calories

Taste

7. Conclusions

Milk is an excellent source of vitamins and minerals, particularly calcium. It has long

been recognised for its important role in bone health. Nutritionists recommend that milk and

other dairy products should be consumed daily as part of a balanced diet. There is some

inaccurate information around in the general community about the health benefits of milk.

Changing the milk intake on the basis of these fallacies may mean unnecessarily restricting

this highly nutritious drink.

The differences between raw milk and powdered milk are in shelf life, nutritional

values, and taste. Raw milk is more expensive than powdered milk, and has a shorter shelf

life. It contains more fat than powdered milk and is much more tastier. Powdered milk can

last longer, as long as it is not mixed with water. It can lose its flavour and nutritional values

after being mixed in water and stored.

Consumption of milk is affecting the environment. Animal agriculture is a very

inefficient use of resources and is damaging to the environment. Water, fertilizer, pesticides

and land are required to grow crops to feed to cows. Energy is needed to harvest the crops,

turn the crops into feed, and then transport the feed to farms. The cows must also be given

water to drink. The waste and methane from factory farms are also an environmental hazard.

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When drinking a glass of milk one is drinking a product made in a factory that only

tastes like milk. Even organic milk is processed in the same way, it just does not have all the

pesticides and hormones.

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8. References

Milk Proteins: From Expression to Food, by Abby Thompson, Mike Boland, Harjinder

Singh, B.S

www.raw-milk-facts.com

"The History Of Milk", About.com. Retrieved 13-8-2010.

http://www.realrawmilkfacts.com/

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The importance of milk for a healthy body

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