Milk is a white liquid produced by the mammalian glands. This is the main source of nutrition for infant mammals (including breastfed humans) before they can digest other types of food. Early lactation milk contains colostrum, which carries the mother's antibodies into her youth and can reduce the risk of many diseases. It contains many other nutrients including protein and lactose. Interspecies of milk consumption is not uncommon, especially among humans, many of whom consume other mammalian milk.
As agricultural products, milk is extracted from non-human mammals during or shortly after pregnancy. Dairy farms produce about 730 million tonnes of milk in 2011, from 260 million dairy cows. India is the largest dairy producer in the world, and is an exporter of skimmed milk powder, but exports some other dairy products. Increased domestic demand for dairy products and large supply-demand gaps could lead India to become a net importer of future dairy products. The United States, India, China and Brazil are the world's largest dairy and dairy exporters. China and Russia are the largest importers of milk and milk products in the world until 2016 when the two countries become independent, contributing to the abundant milk worldwide.
Worldwide, more than six billion people consume milk and dairy products. More than 750 million people live in households of dairy farmers.
Video Milk
Etymology
The term "milk" is derived from "Old English meoluc (West Saxon), milc (Anglian), from Proto-Germanic * milk" (sources also from Old Norse mjolk, Old Frisian melok, Old Saxon miluk, Melk Dutch, Old Miluh German, German Milch, belongs to Gothic) ".
Maps Milk
Consumption type
Milk consumption occurs in two different types overall: a natural source of nutrients for all infant mammals and food products obtained from other mammals for consumption by humans of all ages.
Nutrition for baby mammals
In almost all mammals, milk is given to infants through breastfeeding, either directly or by expressing milk for storage and consumption later. The initial milk of a mammal is called colostrum. Colostrum contains antibodies that provide protection to newborns as well as nutrients and growth factors. The arrangement of colostrum and the period of secretion varies from species to species.
For humans, the World Health Organization recommends exclusive breastfeeding for six months and breast-feeding in addition to other foods for at least two years. In some cultures, it is common to breastfeed children for three to five years, and that period may be longer.
Fresh goat milk 'is sometimes replaced for breast milk, which introduces a child's risk of developing electrolyte imbalances, metabolic acidosis, megaloblastic anemia, and a number of allergic reactions.
Food products for humans
In many cultures, especially in the West, humans continue to consume milk outside of infancy, using other mammalian milk (especially cattle, goats and sheep) as food products. Initially, the ability to digest milk is limited to children because adults do not produce lactase, the enzyme needed to digest lactose in milk. Therefore people change milk into curd, cheese and other products to reduce lactose levels. Thousands of years ago, mutations of opportunity spread in the human population in Europe that allowed the production of lactase in adulthood. This mutation allows milk to be used as a new source of nutrients that can sustain populations when other food sources fail. People process milk into various products such as cream, butter, yogurt, kefir, ice cream, and cheese. Modern industrial processes use milk to produce casein, whey protein, lactose, condensed milk, milk powder, and many other food additives and industrial products.
Milk, butter, and cream have high levels of saturated fat. Lactose sugar is found only in milk, forsythia flowers, and some tropical shrubs. The enzymes needed to digest lactose, lactase, reach the highest levels in the human small intestine after birth and then begin a slow decline unless the milk is consumed regularly. Groups that continue to tolerate milk, however, have often done great creativity in using pet ungulates milk, not only cattle, but also sheep, goats, yak, water buffalo, horses, deer and camels. India is the world's largest producer and consumer of cattle and milk buffalo.
Terminology
In the use of food, the term milk is defined under the Codex Alimentarius standard as: "the normal mammalian secretion of the milking animal obtained from one or more milking without additional or extraction from it, is intended for consumption as liquid milk or for further processing. "This definition thus prevents non-animal products that may resemble milk in color and texture (milk substitutes) such as soy milk, rice milk, almond milk, and coconut milk.
Milk is related to milk and milk production, eg. dairy products.
In addition, substances secreted by pigeons to feed their children are called "plant milk" and are similar to mammalian milk, though not consumed as milk substitutes.
Evolution of lactation
The mammary gland is thought to be derived from the apocrine skin glands. It has been suggested that the original function of lactation (milk production) is to keep eggs moist. Most of the arguments are based on monotremes (egg-laying mammals). The original adaptive significance of milk secretion may be nutrition or immunological protection. This secretion gradually becomes more and more nutritional complexity during evolutionary time.
Cynodonts tritylodontid appears to have demonstrated lactation, based on their pattern of tooth replacements.
History
Humans first learned to consume other mammalian milk regularly after animal domestication during the Neolithic Revolution or agricultural development. This development occurred independently in several global locations from 9000-7000 BC in Mesopotamia up to 3500-3000 BC in America. People first tamed the most important dairy cattle - cattle, sheep and goats - in Southwest Asia, although domestic livestock independently came from wild auroch populations several times since then. Initially the animals are kept for meat, and archaeologist Andrew Sherratt has suggested that dairying work, along with the exploitation of domestic animals for hair and labor, began much later in a separate secondary product revolution in the fourth millennium BC. The Sherratt model is not supported by recent findings, based on analysis of lipid residues in prehistoric pottery, showing that dairying work was done in the early phases of agriculture in Southwest Asia, at least in the seventh millennium BC.
From domestic dairy farms Southeast Asia spread to Europe (starting around 7000 BC but not reaching Britain and Scandinavia until after 4000 BC), and South Asia (7000-5500 BC). The first farmers in Central Europe and Britain were milking their animals. The pastoral and pastoral nomadic economies, which rely largely or exclusively on domestic animals and their products rather than crop farms, were developed as European farmers moved to the grassland Pontic-Caspian in the fourth millennium BC, and then spread across much of the Eurasian pasture. Sheep and goats were introduced to Africa from Southwest Asia, but African cattle may have been kept independently around 7,000-6000 BC. Camels, domesticated in central Arabia in the fourth millennium BC, have also been used as dairy animals in North Africa and the Arabian Peninsula. The earliest record of wound care in Egypt describes burning garments using milk from a baby boy's mother. Across the globe (ie, East and Southeast Asia, America and Australia) milk and dairy products have historically not been a large part of the diet, either because they remain inhabited by hunter-gatherers who do not raise animals or local agricultural economies excluding domestic dairy species. Milk consumption has become common in these areas relatively recently, as a consequence of European colonialism and political domination over most of the world in the last 500 years.
In the Middle Ages, milk was called "white liquor" because alcoholic beverages are safer to consume than water.
Industrialization
The growth of the urban population, coupled with the expansion of the railway network in the mid-19th century, brought a revolution in milk production and supply. Individual railway companies began transporting milk from rural areas to London from the 1840s and 1850s. The first possible example was in 1846, when St Thomas Hospital in Southwark was contracted with a milk supplier outside London to deliver milk through a train. The Great Western Railway was an early and enthusiastic adopter, and began transporting milk to London from Maidenhead in 1860, despite many criticisms. In 1900, the company transported more than 25 million gallons per year. Milk trade grew slowly through the 1860s, but experienced periods of extensive structural change in the 1870s and 1880s.
Market demand began to grow, as consumer purchasing power increased and milk was considered a necessary daily commodity. During the last three decades of the 19th century, milk demand in most countries doubled, or in some cases, tripled. Legislation in 1875 made illegal milk forgery - this combined with a marketing campaign to change the image of milk. The proportion of rural imports by rail as a percentage of total milk consumption in London grew from below 5% in the 1860s to over 96% by the beginning of the 20th century. At that point, the milk supply system is the most organized and integrated of any food product.
The first glass bottle packaging for milk was used in the 1870s. The first company to do so was the New York Dairy Company in 1877. The British Express Dairy Company started the production of glass bottles in 1880. In 1884, Hervey Thatcher, the American inventor of New York, invented a glass bottle of milk, called "Milk Solution Thatcher's Own Flavor, "which is sealed with a waxy paper disk. Then, in 1932, plastic paper-coated milk cartons were introduced commercially.
In 1863, French chemist and biologist Louis Pasteur discovered pasteurization, a method of killing harmful bacteria in drinks and food products. He developed this method during the summer holidays in Arbois, to reduce the acidity of the local wine. He found experimentally that it was enough to heat a young wine only about 50-60 ° C (122-140 ° F) for a short time to kill the microbes, and that the wine could remain aged without sacrificing the final quality. In honor of Pasteur, the process was known as "pasteurization". Pasteurization was originally used as a way to prevent wine and beer from souring. Commercial pasteurization equipment was produced in Germany in the 1880s, and manufacturers adopted the process in Copenhagen and Stockholm in 1885.
Excess production
The continuous increase in milk production efficiency led to an abundance of milk worldwide by 2016. Russia and China became independent and stopped importing milk. Canada has been trying to limit milk production by forcing new farmers/capacity increases to "buy" at C $ 24,000 per head. Importing milk is prohibited. The EU theoretically discontinues subsidizing dairy farms by 2015. Direct subsidies are replaced by "environmental incentives" that result in governments buying milk when prices fall to EUR200 per 1,000 liters (220Ã, gal, 260Ã, gal). The United States has a voluntary insurance program that pays farmers depending on the price of milk and meal costs.
Source
Females of all mammalian species can by definition produce milk, but cow's milk dominates commercial production. In 2011, FAO estimates 85% of all milk worldwide is produced from cattle. Breast milk is not manufactured or distributed either industrially or commercially; however, breast milk banks collect donated milk and distribute it to infants who may benefit from breast milk for various reasons (premature infants, infants with allergies, metabolic diseases, etc.) but can not breastfeed.
In the Western world, cow's milk is produced on an industrial scale and is the most common type of milk consumed. Commercial dairy farms using automatic milking equipment produce most of the milk in developed countries. Dairy cows like Holstein have been selectively bred to increase milk production. About 90% of dairy cattle in the United States and 85% in the United Kingdom are Holsteins. Other dairy cattle in the United States include Ayrshire, Brown Switzerland, Guernsey, Jersey and Milking Shorthorn (Dairy Shorthorn).
Other animal-based sources
In addition to livestock, many types of livestock provide milk used by humans for dairy products. These animals include buffalo, goats, sheep, camels, donkeys, horses, deer and yak. The first four each produce about 11%, 2%, 1.4% and 0.2% of all milk worldwide in 2011.
In Russia and Sweden, small moose elves also exist.
According to the US National Bison Association, American bison (also called American buffalo) is not commercially grown; However, various sources report that cattle produced from bison crosses and domestic livestock are good milk producers, and have been used both during the European settlement of North America and during Beefalo commercial development in the 1970s and 1980s.
Pigs are hardly ever milked, although their milk is similar to cow's milk and is perfect for human consumption. The main reason for this is that the reddening of many small breasts is very complicated, and that the mother of a pig can not store their milk like a cow. Some pig farms sell pork cheese as a new item; cheese is very expensive.
Worldwide production
In 2012, the largest milk and dairy producer is India followed by the United States, China, Pakistan and Brazil. All 28 EU members together produce 153.8 million tonnes of milk by 2013, the largest by a political-economic union.
Increased prosperity in developing countries, as well as increased promotion of milk and dairy products, has led to an increase in milk consumption in developing countries in recent years. In turn, the opportunities presented by this growing market have attracted investment by multinational dairies. However, in many countries, production remains small and provides a significant opportunity to diversify sources of income by small farms. Local milk collection centers, where milk is collected and cooled before being transferred to urban dairy farms, is a good example of where farmers can work on the basis of cooperation, especially in countries like India.
Production generates
FAO reports Israel's dairy farm is the most productive in the world, with a yield of 12,546 kilograms (27,659 pounds) of milk per cow per year. This survey during 2001 and 2007 was conducted by ICAR (International Committee for Animal Records) in 17 developed countries. The survey found that the average number of livestock in developed countries increased from 74 to 99 cows per herd between 2001 and 2007. An average dairy farm has 19 cows per herd in Norway, and 337 in New Zealand. Annual milk production in the same period increased from 7,726 to 8,550 kg (17,033 to 18,850 pounds) per cow in developed countries. The lowest average production was in New Zealand at 3,974 kg (8,761 pounds) per cow. Milk production per tail depends on the production system, cow's nutrition, and only a small genetic potential different from animals. What cows eat has the most impact on the production obtained. New Zealand's cattle with the lowest annual yields year-round, differ from Israel with the highest yields in which cows eat in barns with an energy-rich mix diet.
Milk production per cow in the United States, the world's largest cow milk producer, was 9,954 kg (21,945 pounds) a year in 2010. Conversely, milk per cow in India and China - the second- and third- largest producers - 1,154 kg (2.544 lbs) and 2.282 kg (5,031 pounds) per year.
Price
It was reported in 2007 that with increasing worldwide prosperity and competition for bio-fuel production for feed stock, both demand and milk prices have increased substantially worldwide. Particularly is the rapid rise of milk consumption in China and the rise in milk prices in the United States above the price of government subsidies. In 2010, the Department of Agriculture estimates that farmers will receive an average of $ 1.35 per gallon of US cow's milk (35 cents per liter), which is down 30 cents per gallon from 2007 and well below the break-even point for many farmers.
Physical and chemical properties
Milk is an emulsion or colloid from fat bubbles in water-based liquids containing soluble carbohydrates and mineral aggregates with minerals. Since it is produced as a food source for young people, all of its contents provide benefits for growth. The main requirements are energy (lipids, lactose, and proteins), the biosynthesis of non-essential amino acids supplied by proteins (essential amino acids and amino groups), essential fatty acids, vitamins and inorganic elements, and water.
pH
The milk pH ranges from 6.4 to 6.8 and changes over time. Milk from other bovine and non-bovine mammals vary in composition, but has the same pH.
Lipid
Initially milk fat is secreted in the form of fat clots surrounded by a membrane. Each fatty mass comprises almost entirely from triacylglycerol and is surrounded by a membrane composed of complex lipids such as phospholipids, together with proteins. It acts as an emulsifier that keeps the individual lumps from incorporation and protects the contents of these clumps from various enzymes in the milk liquid portion. Although 97-98% lipid is triacylglycerol, small amounts of di- and monoacylglycerol, free cholesterol and cholesterol esters, free fatty acids, and phospholipids are also present. Unlike proteins and carbohydrates, the fatty composition of milk varies greatly in composition due to differences in genetic, lactation, and nutritional factors among different species.
Like compositions, fat clots vary in size from less than 0.2 to about 15 micrometers in diameter between different species. The diameter may also vary between animals within a species and at different times in milking one animal. In un homogenized cow's milk, fat clots have an average diameter of two to four micrometers and with homogenization, averaging about 0.4 micrometers. Vitamins A, D, E, and K are fat soluble along with essential fatty acids such as linoleic and linolenic acids found in the fatty parts of milk milk.
Protein
Normal cow's milk contains 30-35 grams of protein per liter of which about 80% is regulated in casein micelles. Total protein in milk represents 3.2% of its composition (nutrition table).
Casein
The largest structure in the liquid portion of the milk is "casein micelles": aggregate several thousand protein molecules with superficial resemblance to micelle surfactants, bound with the help of calcium phosphate nanometer-scale particles. Each caseel micelle is approximately round and about one tenth of a micrometer. There are four different types of protein casein:? S1- ,? S2- ,? -, and? -caseins. Collectively, they make up about 76-86% of the protein in milk, by weight. Most of the casein proteins are bound into micelles. There are several competing theories about the exact structure of micelles, but they share one important feature: the outermost layer consists of a string of one type of protein, k-casein, reaching out from the micelle body into the surrounding liquid. These kappa-casein molecules all have negative electrical charges and therefore repel each other, keeping the micelles separated under normal conditions and in a stable colloidal suspension in the liquid around the water.
Milk contains dozens of other proteins in addition to casein and includes enzymes. These other proteins are more water soluble than casein and do not form larger structures. Because proteins remain suspended in the remaining whey when germs thicken into curds, they are collectively known as whey proteins. Whey proteins make up about 20% protein in milk by weight. Lactoglobulin is the most common whey protein with large margins.
Salt, minerals, and vitamins
Mineral or salt milk, is the traditional name for various cations and anions in cow's milk. Calcium, phosphate, magnesium, sodium, potassium, citrate and chloride are all included as a mineral and they usually occur at concentrations of 5-40 mM. The milk salts strongly interact with casein, especially calcium phosphate. It exists in excess and often, a much larger solubility of calcium phosphate. In addition to calcium, milk is the source of many other vitamins. Vitamins A, B6, B12, C, D, K, E, thiamine, niacin, biotin, riboflavin, folate, and pantothenic acid are all present in milk.
Calcium phosphate structure
For many years the most accepted theory of the micelle structure was that it consisted of a ballin casein aggregate, called submicelles, held together by a calcium phosphate relationship. However, there are two new models of casein micelles that dispute different micela structures in micelles.
The first theory to be associated with de Kruif and Holt, proposed that nanoclusters of calcium phosphate and phosphopeptide fraction of beta-casein were central to micellular structures. Particularly in this view, unstructured proteins regulate around calcium phosphate so as to give rise to their structure and thus no special structure is formed.
The second theory proposed by Horne, the growth of calcium phosphate nanoclusters precedes the process of formation of micelles but is limited by the binding of the phosphopeptide loop region of casein. Once bonded, protein interactions are formed and polymerization takes place, in which K-casein is used as the end cap, to form micelles with trapped calcium phosphate nanoclusters.
Some sources suggest that calcium phosphate is trapped in the form of Ca9 (PO 4) 6; whereas, others say it is similar to the brushite CaHPO4 -2H2O mineral structure.
Sugar and Carbohydrates
Milk contains several different carbohydrates including lactose, glucose, galactose, and other oligosaccharides. Lactose gives a sweet taste to milk and accounts for about 40% of all calories of cow's milk. Lactose is a disaccharide mixture of two simple sugars, glucose and galactose. Cow's milk averages 4.8% of anhydrous lactose, which accounts for about 50% of the total skim milk solids. Lactose levels depend on the type of milk because other carbohydrates can be present at higher concentrations of the lactose in milk.
Miscellaneous content
Other components found in raw cow's milk are live white blood cells, mammary glands, various bacteria, and a large number of active enzymes.
Appearance
The two smaller fat clusters and caseel micelles, large enough to bend light, contribute to the opaque white color of milk. Fat clots contain some yellow-orange carotene, enough in some breeds (such as Guernsey and Jersey cows) to give a golden or "cream" color to a glass of milk. Riboflavin in the whey portion of milk has a greenish color, which can sometimes be seen in skim milk or whey products. Fat-free skim milk only has casein micelles to diffuse light, and they tend to spread shorter wavelength blue light than red, feeding a bluish color scheme.
Processing
In most Western countries, centralized dairy facilities process milk and milk-derived products, such as cream, butter, and cheese. In the US, dairies are usually local firms, whereas in the Southern Hemisphere facility it may be run by large multinational corporations like Fonterra.
Pasteurization
Pasteurization is used to kill harmful bacterial pathogens by heating milk in a short time and then immediately cooling it down. Types of pasteurized milk include full cream, reduced fat, skim milk, fortified calcium, seasoned, and UHT. A standard 72-degree (RTST) high temperature (HTST) process for 15 seconds kills pathogenic bacteria in milk, making it safe to drink for up to three weeks if kept cool. Dairies print out the best before the date on each container, after which the store releases unsold milk from their shelves.
The side effect of heating pasteurization is that some of the vitamins and minerals are lost. Calcium and dissolved phosphorus decreased by 5%, thiamin and vitamin B12 by 10%, and vitamin C by 20%. Because the disadvantages are small compared to the large amounts of both existing B vitamins, milk continues to provide large amounts of thiamin and vitamin B12. The loss of vitamin C is not nutritionally significant, because milk is not an important food source of vitamin C.
Filtration
Microfiltration is a process that partially replaces pasteurization and produces milk with fewer microorganisms and longer shelf life without flavor change in milk. In this process, the cream is separated from skim milk and pasteurized in the usual way, but skim milk is forced through a ceramic microfilter that traps 99.9% of microorganisms in milk (compared to 99.999% killing of microorganisms in standard HTST pasteurization). Skim milk is then combined with pasteurized cream to rearrange the original milk composition.
Ultrafiltration uses finer filters than microfiltration, which allows lactose and water to pass through while maintaining fat, calcium and protein. Like microfiltration, fat can be removed before filtration and added back thereafter. Ultrafiltered milk is used cheesemaking, because it has reduced the volume for the given protein content, and is sold directly to the consumer as a higher protein, lower sugar content, and creamier alternatives to regular milk.
Cream and homogenization
After standing for 12 to 24 hours, fresh milk has a tendency to be separated into a layer of high fat cream over a larger and lower fat layer of milk. Cream is often sold as a separate product with its own use. Today the separation of cream from milk is usually done quickly in centrifugal cream separators. Fat clumps rise to the top of the milk container because the fat is less dense than water. The smaller the bubble, the more power the other molecular level prevents this from happening. In fact, the cream rises in cow's milk much faster than a simple model that would predict: rather than isolated clumps, the fat in milk tends to form into clusters containing about one million clumps, which are united by a number of whey minor proteins. This cluster increases faster than individual clods. The fatty clumps in milk from goats, sheep, and buffaloes do not form easily and smaller groups to start, resulting in a slower separation of cream from this milk.
Milk is often homogenized, a treatment that prevents the cream layer separating milk. Milk is pumped at high pressure through very narrow tubes, breaking down fat clumps through turbulence and cavitation. A large number of smaller particles have more total surface area than the smaller number of larger ones, and the original fatty globule membranes can not completely cover them. Maceel casein is attracted to the surface of newly exposed fat. Nearly a third of micelles in milk eventually participate in this new membrane structure. Casein weighs on clots and disrupts the groupings that accelerate separation. Clots of open fat are susceptible to certain enzymes present in milk, which can break down fat and produce rancid odors. To prevent this, the enzymes are inactivated by milk pasteurization immediately before or during homogenization.
Homogeneous milk is blander but tastes creamier in the mouth rather than homogenized. Whiter and more resistant to developing flavors. Creamline (or cream-top) milk is not homogenized. It may or may not be pasteurized. High pressure homogenized milk, sometimes labeled as "ultra-homogenized," has a longer shelf life than normal homogenized milk at lower pressures.
The homogenization process increases the shelf life of milk by reducing the radius of fat clots and other particles (according to Stokes law) thereby delaying the agglomeration rate.
UHT
Ultra Heat Treatment (UHT), is a type of milk treatment where all bacteria are destroyed with high heat to extend shelf life up to 6 months, as long as the package is not opened. Milk was first homogenized and then heated to 138 degrees Celsius for 1-3 seconds. Milk immediately cooled and packed into sterile containers. As a result of this treatment, all pathogenic bacteria in milk are destroyed, unlike when new milk is pasteurized. Milk will now be stored for 6 months if it has not been opened. UHT milk does not need to be cooled until the package is opened, which makes it easier to send and store. But in this process there is a loss of vitamin B1 and vitamin C and there is also a slight change in the taste of milk.
Nutrition and health
The milk composition differs widely among species. Factors such as protein type; proportion of protein, fat, and sugar; levels of various vitamins and minerals; and the size of fat clumps of butter, and the strength of the curds are among those that may vary. As an example:
- Breast milk contains, on average, 1.1% protein, 4.2% fat, 7.0% lactose (sugar), and supplies 72 kcal of energy per 100 grams.
- Cow's milk contains, on average, 3.4% protein, 3.6% fat, and 4.6% lactose, 0.7% mineral and 66 kcal energy supplies per 100 grams. See also Further nutritional values ​​at
Donkey and horse milk have the lowest fat content, while seal and whale milk contains more than 50% fat.
Milk cow
This composition varies with the breed, the animal, and the point in the lactation period.
The protein range for these four offspring was 3.3% to 3.9%, while the lactose range was 4.7% to 4.9%.
The percentage of milk fat can be manipulated by a dairy farmer's diet formulation strategy. Mastitis infection can cause fat levels to decrease.
Nutritional value
Processed cow's milk contains different amounts of fat during the 1950s. One cup (250 mL) cow's milk 2% -contains 285 mg of calcium, representing 22% to 29% of the recommended daily intake (DRI) of calcium for adults. Depending on age, milk contains 8 grams of protein, and a number of other nutrients (either naturally or through fortification) include:
- Biotin
- Iodine
- Magnesium
- Pantothenic acid
- Potassium
- Riboflavin
- Selenium
- Thiamine
- Vitamin A
- Vitamin B 12
- Vitamin D
- Vitamin K
The amount of calcium from milk absorbed by the human body is disputed. Calcium from dairy products has greater bioavailability than calcium from certain vegetables, such as spinach, which contains high levels of calcium-chelating agents, but the same bioavailability or less than calcium from low-oxalic vegetables such as kale, broccoli, or other vegetables. in the genus Brassica .
Milk as a source of calcium has been questioned in the media, but scientific research does not support the hypothesis of milk induced acidosis. The hypothesis is that acidosis will cause calcium storage in the bone to neutralize the pH level (also known as the ash-acid hypothesis). The study found no association between metabolic acidosis and milk consumption.
Suggested consumption
The US federal government's Dietary Guidelines for America 2010 recommends consuming three glasses of low fat or low fat milk for adults and children 9 and older (less for small children) per day. These recommendations are debated by some health researchers who are calling for more research on this issue, given that there are other sources for calcium and vitamin D. Researchers also claim that the recommendations have been too influenced by the American dairy industry, and that milk may be better for health because his increased ability to satisfy his hunger.
Medical research
A 2008 review found evidence to suggest that effective milk consumption encourages muscle growth. Several studies have shown that conjugated linoleic acid, which can be found in dairy products, is an effective supplement for reducing body fat. With regard to milk claims promoting stronger bones, there is no association between milk consumption or excess calcium intake and reduced fracture risk.
In 2011, the Journal of Bone and Mineral Research published a meta-analysis that checks whether milk consumption can protect against hip fractures in middle-aged and older adults. The study found no association between drinking milk and lower fracture rates. In 2014, JAMA Pediatrics published the report after monitoring nearly 100,000 men and women for more than two decades. Subjects were asked to report how much milk they consumed as teenagers, and followed to see if there was a connection with the possibility of a hip fracture in the future, was not there. A study published in BMJ followed by more than 45,000 men and 61,000 women in Sweden age 39 and older had similar results. Adult milk consumption is associated with no protection for men, and an increased risk of fractures in women. The risk of fractures increased 16 percent in women who drank three or more glasses per day, and the risk of hip fractures increased 60 percent. It was also associated with an increased risk of death in both sexes.
Milk and dairy products have the potential to cause serious infections in newborns. Unpasteurized milk and cheese can increase bacterial growth Lactose intolerance
Lactose, the disaccharide sugar component of all milk, should be cleaved in the small intestine by lactase enzymes, for its constituents, galactose and glucose, to be absorbed. Lactose intolerance is a condition in which people have symptoms because there are not enough lactase enzymes in the small intestine. Those affected vary in the amount of lactose they can tolerate before symptoms develop. This may include abdominal pain, bloating, diarrhea, gas, and nausea. The severity depends on the number of people who eat or drink. Those exposed can usually drink at least one cup of milk without developing significant symptoms, with a greater amount tolerated if taken with meals or throughout the day.
Lactose intolerance does not cause damage to the gastrointestinal tract. There are four types: primary, secondary, developmental, and congenital. Primary lactose intolerance is when the amount of lactase decreases with age. Secondary lactose intolerance is due to injury to the small intestine such as from infection, celiac disease, inflammatory bowel disease, or other diseases. Lactose intolerance progression can occur in premature infants and usually improves over a short period of time. Congenital lactose intolerance is a very rare genetic disorder in which little or no lactase is made from birth. When lactose intolerance is due to secondary lactase deficiency, treatment of the underlying disease allows lactase activity to return to normal levels. Lactose intolerance is different from milk allergy.
The number of people with lactose intolerance is unknown. Some human populations have developed persistence of lactase, in which lactase production continues to mature as possible in response to the benefits of being able to digest milk from farm animals. The percentage of the population that has decreased lactase because of their age is less than 10% in Northern Europe and as high as 95% in parts of Asia and Africa.
Possible danger
Several studies have shown that milk consumption may increase the risk of suffering from certain health problems. Cow milk allergy (CMA) is an immunologic, rarely fatal, side effect on one or more cow's milk proteins. Milk from any mammal contains amino acids and microRNAs that affect the metabolism and growth of the drinker; This "programming" is beneficial to the natural consumer of milk, which is a baby of the same species as the milk producers, but post-baby and trans-species milk consumption affects the metabolic pathway of mTORC1 and can increase the diseases of civilization such as obesity and diabetes.
Milk contains exogenous opioid peptides called exorphins that include opioid food peptides such as gluten exorphin and opioid food peptides. Exorphins mimic the actions of endorphines because they bind to the same opioid receptor in the brain. Exorphin in milk is called casein, a substance damaged in the human stomach to produce an opioid peptide casomorphin. In the early 1990s it was hypothesized that casomorphins can cause or worsen autism spectrum disorders, and casein-free diets are widely promoted. Research that supports this claim has significant deficiencies, and the data are inadequate to guide the recommendation of autism treatment.
Recent assessments by the World Cancer Research Fund and the American Institute for Cancer Research found that most individual epidemiological studies show an increased risk of prostate cancer with increased intake of milk or milk products. "The cohort meta-data analysis yielded evidence of a clear dose-response relationship between advanced/aggressive cancer risk with milk intake, and between all risks of prostate cancer and milk and milk products." Possible mechanisms include inhibition of vitamin D conversion to its active metabolite, 1,25-dihydroxy vitamin D3 by calcium (which some evidence suggests increased cell proliferation in the prostate), and increased levels of insulin-like-1 growth factor (IGF-1). Some sources show a correlation between the high calcium intake of milk, in particular, and prostate cancer, consistent with calcium/vitamin-based mechanisms. Overall, the WCRF/AICR panel concluded that "inconsistent evidence from both cohort and case-control studies. limited that suggests that milk and dairy products are the cause of prostate cancer. "
Medical studies have also shown the possible link between milk consumption and exacerbations of diseases such as Crohn's disease, Hirschsprung's infectious disease symptoms in infants with existing cow's milk allergies, and aggravation of BehÃÆ'§et's disease.
Milk at school in the USA
Milk should be offered every meal if the school district of the United States wants to get a replacement from the federal government. A quarter of the largest school districts in the US offer rice or soy milk and nearly 17% of all US school districts offer lactose-free milk. Seventy-one percent of the milk served in the US school cafeteria is flavored, causing some school districts to propose a ban because seasoning milk has added sugar. (Although some aromatic dairy products use artificial sweeteners instead.) Boulder, Colorado school district banned scented milk in 2009 and instead installed a dispenser that made milk cooler.
Supplementation of growth hormone bovin
Since November 1993, recombinant bovine somatotropin (rbST), also called rBGH, has been sold to dairy farmers under FDA approval. Cattle produce natural cow growth hormones, but some manufacturers manage an additional recombinant version of BGH produced through genetically modified E. coli to increase milk production. Bovine growth hormone also stimulates liver production from insulin like growth factor 1 (IGF1). The US Food and Drug Administration, the National Institutes of Health and the World Health Organization have reported that both of these compounds are safe for human consumption by the amount available.
Milk from rBST-administered cows can be sold in the United States, and the FDA states that no significant difference was observed between milk derived from rBST-treated and those from non-rBST-treated cattle. Milk that advertises that it comes from cows that are not treated with rBST, is required to state these findings on the label.
Cows receiving rBGH supplements may experience more frequent udder infections known as mastitis. Problems with mastitis have resulted in Canada, Australia, New Zealand, and Japan banning milk from cows treated rBST. Mastitis, among other diseases, may be responsible for the fact that the level of white blood cells in milk varies naturally.
rBGH is also prohibited in the European Union.
Criticism
Vegans and some other vegetarians do not consume milk for reasons that are mostly related to animal rights and environmental issues. They may object to the features of dairy farms including the need to keep dairy cows pregnant, killing almost all descendants of dairy men (either by disposal shortly after birth, for beef production, or for beef), routine separation of mothers and calves as soon as born, other inhumane treatment of dairy cattle, and cattle extermination after their productive lives.
Some people criticize the promotion of milk consumption by the American government. Their main concern is the financial interest the American government takes in the dairy industry, promoting milk as the best source of calcium. All US schools that are part of the federally-funded National School Lunch Act are required by the federal government to provide milk for all students. The Dietary Supplements Office recommends that healthy adults between the ages of 19 and 50 get about 1,000 mg of calcium per day.
Milk production is also an intensive resource. On a global weighted average, for the production of certain milk volumes, a thousand times more water should be used.
Varieties and brands
Dairy products are sold in a number of varieties by type/degree:
- additives (eg vitamins, flavors)
- age (eg cheddar, old cheddar)
- coagulation (eg cottage cheese) Agricultural methods
- (eg organic, grass eating)
- fat content (eg half and half, 3% milk fat, 2% milk, 1% milk, skim milk) Fermentation
- (eg buttermilk)
- flavoring (eg chocolate and strawberries)
- homogenization (eg, top of cream)
- packaging (eg bottles, cartons, bags)
- pasteurization (eg raw milk, pasteurized milk)
- reduction or elimination of lactose
- species (eg cows, goats, sheep)
- sweetener (eg, chocolate milk and strawberries)
- water content (eg dried milk powder, condensed milk, ultrafilter milk)
Milk preserved by the UHT process does not need to be cooled before it is opened and has a longer shelf life (six months) than milk in regular packaging. Usually sold without recycling in the UK, US, Europe, Latin America and Australia.
Lactose reduction or elimination
Lactose-free milk can be produced by passing milk through a lactase enzyme bound to an inert carrier. After the molecule is cleaved, there is no adverse lactose effect. Forms are available with a reduction in the amount of lactose (usually 30% of normal), and alternatives with nearly 0%. The only real difference from ordinary milk is a slightly sweeter taste due to the generation of glucose by lactose cleavage. However, it does not contain more glucose, and is nutritionally identical to regular milk.
Finland, where about 17% of the Finnish-speaking population has hypolactasia, has had "HYLA" (abbreviation for lactose hydraulic ) products available for years. Lactose low-grade lactose cow's milk products, from ice cream to cheese, are enzymatically hydrolyzed to glucose and galactose. The ultra-pasteurization process, combined with aseptic packaging, ensures long shelf life. In 2001, Valio launched a lactose-free milk drink that was not as sweet as HYLA milk but had a fresh taste of regular milk. Valio patented a chromatographic separation method for the removal of lactose. Valio also markets these products in Sweden, Estonia, Belgium, and the United States, where the company says the use of ultrafiltration.
In the UK, where an estimated 4.7% of the population is affected by lactose intolerance, Lactofree produces milk, cheese, and yoghurt products containing only 0.03% lactose.
To aid digestion in those with lactose intolerance, milk with additional bacterial cultures such as Lactobacillus acidophilus ("acidophilus milk") and bifidobacteria ("a/B milk") are available in some areas. Other milk with bacterial cultures Lactococcus lactis ("cultivated buttermilk") is often used in cooking to replace the traditional use of deteriorated milk naturally, which has become rare due to pasteurization, which also kills the Lactococcus bacteria that occur naturally.
Lactose-free milk and lactose can also be produced through ultra filtration, which removes smaller molecules such as lactose and water while leaving behind calcium and protein behind. Milk produced by this method has a lower sugar content than regular milk.
Additives and flavor
In areas where livestock (and often people) live inside homes, commercially sold milk usually contains vitamin D that is added to cover the shortage of UVB radiation exposure.
Low-fat milk often adds vitamin A palmitate to compensate for the loss of vitamins during fat removal; in the United States, this causes a decrease in milk fat that has a higher vitamin A content than whole milk.
Milk often has seasonings added to it for a better taste or as a means to increase sales. Chocolate milk has been sold for years and has been followed recently by strawberry and other milk. Some nutritionists have criticized spiced milk for adding sugar, usually in the form of high fructose corn syrup, to a childhood diet that is already commonly obese in the United States.
Distribution
Due to the short shelf life of ordinary milk, it is used to be sent to households daily in many countries; however, increased cooling at home, changing the pattern of food shopping because of supermarkets, and higher home delivery costs mean daily delivery by milk carriers is no longer available in most countries.
Australia and New Zealand
In Australia and New Zealand, before the metric, milk is generally distributed in 1 pint glass bottles (568 Ã, mL). In Australia and Ireland there is a government-funded "free milk for school" program, and milk is distributed during morning breaks in 1/3 pint bottles. With conversion to metric size, the dairy industry is worried that replacing pint bottles with 500 ml bottles will result in a 13.6% reduction in milk consumption; then, all the pint bottles are pulled back and replaced with 600 bottles of milk mL. Over time, as the cost of collecting, transporting, storing, and cleaning glass bottles continues to rise, they are replaced by cardboard. A number of designs are used, including tetrahedron that can be packed without waste space, and can not be accidentally knocked. (slogan: No more crying over spilled milk.) However, the industry has finally established a design similar to that used in the United States.
Milk is now available in various sizes in paperboard cartons (250 mL, 375 mL, 600 ml, 1 liter and 1.5 liter) and plastic bottles (1, 2 and 3 liters). A significant addition to the market is "longevity" (UHT) milk, commonly available in 1 and 2 liter rectangular cardboard cartons. In urban and suburban areas where there is sufficient demand, home delivery is still available, although in these suburbs it is often 3 times per week rather than daily. Another significant and popular addition to the market has been flavored milk - for example, as mentioned above, Farmers Union Iced Coffee outperforms Coca-Cola in South Australia.
India
In rural India, milk is sent home, daily, by local milkmen carrying large quantities in metal containers, usually by bicycle. In other parts of the Indian metropolis, milk is usually bought or shipped in plastic bags or cartons through a store or supermarket.
The current flow of milk chains in India is from milk producers to dairy collectors. Then transported to the center of milk and bulk cold is transported to the processing plant, then to the sales agent and finally to the consumer.
A 2011 survey by India's Food Safety and Standards Agency found that nearly 70 percent of samples did not conform to the established standards for milk. The study found that due to lack of hygiene and sanitation in handling and packing milk, the detergent (used during cleaning operations) was not washed properly and found its way into milk. About eight percent of the samples in the survey were found to have detergents, which are harmful to health.
Pakistan
In Pakistan, milk is provided in a jar. Milk has become a staple food, especially among the grazing tribes in the country.
United Kingdom
Since the late 1990s, milk purchasing patterns have changed drastically in the UK. The classical milkman, who travels his local milk round (route) using a milk buil (often battery-powered) during the early hours and delivering milk in a 1 pint glass bottle with a peak of aluminum foil straight to the household, almost disappears. The two main reasons for the reduction in UK home delivery by milkmen are the household refrigerators (which reduce the need for daily milk delivery) and the use of private cars (which have increased supermarket shopping). Another factor is cheaper to buy milk from supermarkets than from home delivery. In 1996, more than 2.5 billion liters of milk was still sent by milkmen, but in 2006 only 637 million liters (13% of milk consumed) were shipped by about 9,500 milk carriers. In 2010, the estimated number of milk carriers dropped to 6,000. Assuming that shipments per milkman are the same as in 2006, this means delivery of milk carriers now only reaches 6-7% of all milk consumed by UK households (6.7 billion liters in 2008/2009).
Almost 95% of all milk in England is sold in stores today, mostly in plastic bottles of various sizes, but some also in milk cartons. Milk is almost never sold in glass bottles in stores in England.
United States
In the United States, glass milk bottles have been replaced mostly with milk cartons and plastic jugs. Milk gallons are almost always sold in jugs, while half a gallon and liter can be found on both cardboard and plastic pitchers, and the smaller size is almost always in cardboard.
The "half pint" (236,6Ã, mL, / 12 Ã, impÃ,pt) milk carton is the traditional unit as a feeding component Even though some companies have replaced unit sizes with plastic bottles, which are also available in retail in size 6- and 12-pack.
Packaging
Practically everywhere, condensed milk and evaporated milk are distributed in metal cans, 250 and 125Ã, mL paper containers and 100 and 200Ã, mL squeeze tubes, and milk powder (skim and whole) are distributed in boxes or bags.
Fermented and fermented milk products
When raw milk is left standing for a while, it turns out to be "sour". This is the result of fermentation, in which lactic acid bacteria ferment lactose in milk to lactic acid. Old fermentation can cause uncomfortable milk for consumption. The fermentation process is utilized by the introduction of bacterial cultures (eg Lactobacilli sp., Streptococcus sp., Leuconostoc sp. , etc.) to produce various fermented milk products. The decrease in pH from the accumulation of lactic acid denied the protein and caused milk to undergo different transformations in appearance and texture, ranging from aggregate to subtle consistency. Some of these products include sour cream, yogurt, cheese, buttermilk, viili, kefir, and whiskers. View Milk products for more information.
Pasteurization of cow's milk initially destroys potential pathogens and increases shelf life, but ultimately results in decay that makes it unsuitable for consumption. This causes it to cause unpleasant odors, and milk is considered inedible due to bad taste and risks of food poisoning increase. In raw milk, the presence of lactic acid-producing bacteria, in appropriate conditions, fermentes the lactose present in lactic acid. Increased acidity in turn prevents the growth of other organisms, or slows their growth significantly. During pasteurization, however, these lactic acid bacteria are largely destroyed.
To prevent spoilage, milk can be stored in refrigerators and stored between 1 and 4 Â ° C (34 and 39 Â ° F) in bulk tanks. Most of the milk is pasteurized by a short warm up and then cooled to allow transportation from farms to local markets. Milk decomposition can be prevented using ultra-high temperature (UHT) treatments. Processed milk can be stored without refrigeration for several months until it is open but has a distinctive "mature" taste. Condensed milk, made by removing most of the water, can be stored in a can for years, not cooled, like milk that evaporates. The most durable form of milk is milk powder, which is produced from milk by removing almost all water. The moisture content is usually less than 5% in both powdered and spray-dried powdered milk.
A milk freeze can cause fat globule aggregation during liquefaction, which results in a milk layer and
Source of the article : Wikipedia
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