Milk is a nutrient-rich, white liquid food produced by the mammary glands of mammals. It is the primary source of nutrition for infant mammals (including humans who are breastfed) before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mother's antibodies to its young and can reduce the risk of many diseases. It contains many other nutrients including protein and lactose. Interspecies consumption of milk is not uncommon, particularly among humans, many of whom consume the milk of other mammals.
As an agricultural product, milk, also called dairy milk, is extracted from farm animals during or soon after pregnancy. Dairy farms produced about 730 million tonnes of milk in 2011, from 260 million dairy cows. India is the world's largest producer of milk, and is the leading exporter of skimmed milk powder, yet it exports few other milk products. The ever increasing rise in domestic demand for dairy products and a large demand-supply gap could lead to India being a net importer of dairy products in the future. The United States, India, China and Brazil are the world's largest exporters of milk and milk products. China and Russia were the world's largest importers of milk and milk products until 2016 when both countries became self-sufficient, contributing to a worldwide glut of milk.
Throughout the world, more than six billion people consume milk and milk products. Over 750 million people live in dairy farming households.
The term "milk" comes from "Old English meoluc (West Saxon), milc (Anglian), from Proto-Germanic *meluks "milk" (source also of Old Norse mjolk, Old Frisian melok, Old Saxon miluk, Dutch melk, Old High German miluh, German Milch, Gothic miluks)".
In food use, from 1961, the term milk has been defined under Codex Alimentarius standards as: "the normal mammary secretion of milking animals obtained from one or more milkings without either addition to it or extraction from it, intended for consumption as liquid milk or for further processing." The term dairy relates to animal milk and animal milk production.
The definition above precludes non-animal products which resemble dairy milk in color and texture, such as almond milk, coconut milk, rice milk, and soy milk. In English, the word "milk" has been used to refer to "milk-like plant juices" since 1200 AD. In the USA, (mostly plant-based) milk alternatives now command 13% of the "milk" market, leading the US dairy industry to attempt, multiple times, to sue producers of dairy milk alternatives, to have the name "milk" limited to animal milk, so far without success.
Milk consumption occurs in two distinct overall types: a natural source of nutrition for all infant mammals and a food product obtained from other mammals for consumption by humans of all ages.
In almost all mammals, milk is fed to infants through breastfeeding, either directly or by expressing the milk to be stored and consumed later. The early milk from mammals is called colostrum. Colostrum contains antibodies that provide protection to the newborn baby as well as nutrients and growth factors. The makeup of the colostrum and the period of secretion varies from species to species.
For humans, the World Health Organization recommends exclusive breastfeeding for six months and breastfeeding in addition to other food for up to two years of age or more. In some cultures it is common to breastfeed children for three to five years, and the period may be longer.
Fresh goats' milk is sometimes substituted for breast milk, which introduces the risk of the child developing electrolyte imbalances, metabolic acidosis, megaloblastic anemia, and a host of allergic reactions.
In many cultures, especially in the West, humans continue to consume milk beyond infancy, using the milk of other mammals (especially cattle, goats and sheep) as a food product. Initially, the ability to digest milk was limited to children as adults did not produce lactase, an enzyme necessary for digesting the lactose in milk. People therefore converted milk to curd, cheese and other products to reduce the levels of lactose. Thousands of years ago, a chance mutation spread in human populations in Europe that enabled the production of lactase in adulthood. This mutation allowed milk to be used as a new source of nutrition which could sustain populations when other food sources failed. Milk is processed into a variety of products such as cream, butter, yogurt, kefir, ice cream, and cheese. Modern industrial processes use milk to produce casein, whey protein, lactose, condensed milk, powdered milk, and many other food-additives and industrial products.
Whole milk, butter and cream have high levels of saturated fat. The sugar lactose is found only in milk, forsythia flowers, and a few tropical shrubs. The enzyme needed to digest lactose, lactase, reaches its highest levels in the human small intestine after birth and then begins a slow decline unless milk is consumed regularly. Those groups who do continue to tolerate milk, however, often have exercised great creativity in using the milk of domesticated ungulates, not only of cattle, but also sheep, goats, yaks, water buffalo, horses, reindeer and camels. India is the largest producer and consumer of cattle and buffalo milk in the world.
|Country||Milk (liters)||Cheese (kg)||Butter (kg)|
Humans first learned to consume the milk of other mammals regularly following the domestication of animals during the Neolithic Revolution or the development of agriculture. This development occurred independently in several global locations from as early as 9000–7000 BC in Mesopotamia to 3500–3000 BC in the Americas. People first domesticated the most important dairy animals – cattle, sheep and goats – in Southwest Asia, although domestic cattle had been independently derived from wild aurochs populations several times since. Initially animals were kept for meat, and archaeologist Andrew Sherratt has suggested that dairying, along with the exploitation of domestic animals for hair and labor, began much later in a separate secondary products revolution in the fourth millennium BC. Sherratt's model is not supported by recent findings, based on the analysis of lipid residue in prehistoric pottery, that shows that dairying was practiced in the early phases of agriculture in Southwest Asia, by at least the seventh millennium BC.
From Southwest Asia domestic dairy animals spread to Europe (beginning around 7000 BC but did not reach Britain and Scandinavia until after 4000 BC), and South Asia (7000–5500 BC). The first farmers in central Europe and Britain milked their animals. Pastoral and pastoral nomadic economies, which rely predominantly or exclusively on domestic animals and their products rather than crop farming, were developed as European farmers moved into the Pontic-Caspian steppe in the fourth millennium BC, and subsequently spread across much of the Eurasian steppe. Sheep and goats were introduced to Africa from Southwest Asia, but African cattle may have been independently domesticated around 7000–6000 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 Egyptian records of burn treatments describe burn dressings using milk from mothers of male babies. In the rest of the world (i.e., East and Southeast Asia, the Americas and Australia) milk and dairy products were historically not a large part of the diet, either because they remained populated by hunter-gatherers who did not keep animals or the local agricultural economies did not include domesticated dairy species. Milk consumption became common in these regions comparatively recently, as a consequence of European colonialism and political domination over much of the world in the last 500 years.
The growth in urban population, coupled with the expansion of the railway network in the mid-19th century, brought about a revolution in milk production and supply. Individual railway firms began transporting milk from rural areas to London from the 1840s and 1850s. Possibly the first such instance was in 1846, when St Thomas's Hospital in Southwark contracted with milk suppliers outside London to ship milk by rail. The Great Western Railway was an early and enthusiastic adopter, and began to transport milk into London from Maidenhead in 1860, despite much criticism. By 1900, the company was transporting over 25 million gallons annually. The milk trade grew slowly through the 1860s, but went through a period of extensive, structural change in the 1870s and 1880s.
Urban demand began to grow, as consumer purchasing power increased and milk became regarded as a required daily commodity. Over the last three decades of the 19th century, demand for milk in most parts of the country doubled, or in some cases, tripled. Legislation in 1875 made the adulteration of milk illegal – 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 under 5% in the 1860s to over 96% by the early 20th century. By that point, the supply system for milk was the most highly 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 may have been the New York Dairy Company in 1877. The Express Dairy Company in England began glass bottle production in 1880. In 1884, Hervey Thatcher, an American inventor from New York, invented a glass milk bottle, called "Thatcher's Common Sense Milk Jar," which was sealed with a waxed paper disk. Later, in 1932, plastic-coated paper milk cartons were introduced commercially.
In 1863, French chemist and biologist Louis Pasteur invented pasteurization, a method of killing harmful bacteria in beverages and food products. He developed this method while on summer vacation in Arbois, to remedy the frequent acidity of the local wines. He found out experimentally that it is sufficient to heat a young wine to only about 50–60 °C (122–140 °F) for a brief time to kill the microbes, and that the wine could be nevertheless properly aged without sacrificing the final quality. In honor of Pasteur, the process became known as "pasteurization". Pasteurization was originally used as a way of preventing wine and beer from souring. Commercial pasteurizing equipment was produced in Germany in the 1880s, and producers adopted the process in Copenhagen and Stockholm by 1885.
Continued improvements in the efficiency of milk production led to a worldwide glut of milk by 2016. Russia and China became self-sufficient and stopped importing milk. Canada has tried to restrict milk production by forcing new farmers/increased capacity to "buy in" at C$24,000 per cow. Importing milk is prohibited. The European Union theoretically stopped subsidizing dairy farming in 2015. Direct subsidies were replaced by "environmental incentives" which results in the government buying milk when the price falls to €200 per 1,000 liters (220 imp gal; 260 U.S. gal). The United States has a voluntary insurance program that pays farmers depending upon the price of milk and the cost of feed.
The females of all mammal species can by definition produce milk, but cow's milk dominates commercial production. In 2011, FAO estimates 85% of all milk worldwide was produced from cows. Human milk is not produced or distributed industrially or commercially; however, human milk banks collect donated human breastmilk and redistribute it to infants who may benefit from human milk for various reasons (premature neonates, babies with allergies, metabolic diseases, etc.) but who cannot breastfeed.
In the Western world, cow's milk is produced on an industrial scale and is by far the most commonly consumed form of milk. Commercial dairy farming using automated milking equipment produces the vast majority of milk in developed countries. Dairy cattle such as the Holstein have been bred selectively for increased milk production. About 90% of the dairy cows in the United States and 85% in Great Britain are Holsteins. Other dairy cows in the United States include Ayrshire, Brown Swiss, Guernsey, Jersey and Milking Shorthorn (Dairy Shorthorn).
Aside from cattle, many kinds of livestock provide milk used by humans for dairy products. These animals include water buffalo, goat, sheep, camel, donkey, horse, reindeer and yak. The first four respectively produced about 11%, 2%, 1.4% and 0.2% of all milk worldwide in 2011.
According to the U.S. National Bison Association, American bison (also called American buffalo) are not milked commercially; however, various sources report cows resulting from cross-breeding bison and domestic cattle are good milk producers, and have been used both during the European settlement of North America and during the development of commercial Beefalo in the 1970s and 1980s.
Swine are almost never milked, even though their milk is similar to cow's milk and perfectly suitable for human consumption. The main reasons for this are that milking a sow's numerous small teats is very cumbersome, and that sows can not store their milk as cows can. A few pig farms do sell pig cheese as a novelty item; these cheeses are exceedingly expensive.
In 2012, the largest producer of milk and milk products was India followed by the United States of America, China, Pakistan and Brazil. All 28 European Union members together produced 153.8 million tonnes of milk in 2013, the largest by any politico-economic union.
Increasing affluence in developing countries, as well as increased promotion of milk and milk products, has led to a rise in milk consumption in developing countries in recent years. In turn, the opportunities presented by these growing markets have attracted investments by multinational dairy firms. Nevertheless, in many countries production remains on a small scale and presents significant opportunities for diversification of income sources by small farms. Local milk collection centers, where milk is collected and chilled prior to being transferred to urban dairies, are a good example of where farmers have been able to work on a cooperative basis, particularly in countries such as India.
FAO reports Israel dairy farms are the most productive in the world, with a yield of 12,546 kilograms (27,659 lb) milk per cow per year. This survey over 2001 and 2007 was conducted by ICAR (International Committee for Animal Recording) across 17 developed countries. The survey found that the average herd size in these developed countries increased from 74 to 99 cows per herd between 2001 and 2007. A dairy farm had an average of 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 lb) per cow in these developed countries. The lowest average production was in New Zealand at 3,974 kg (8,761 lb) per cow. The milk yield per cow depended on production systems, nutrition of the cows, and only to a minor extent different genetic potential of the animals. What the cow ate made the most impact on the production obtained. New Zealand cows with the lowest yield per year grazed all year, in contrast to Israel with the highest yield where the cows ate in barns with an energy-rich mixed diet.
The milk yield per cow in the United States, the world's largest cow milk producer, was 9,954 kg (21,945 lb) per year in 2010. In contrast, the milk yields per cow in India and China – the second and third largest producers – were respectively 1,154 kg (2,544 lb) and 2,282 kg (5,031 lb) per year.
It was reported in 2007 that with increased worldwide prosperity and the competition of bio-fuel production for feed stocks, both the demand for and the price of milk had substantially increased worldwide. Particularly notable was the rapid increase of consumption of milk in China and the rise of the price of milk in the United States above the government subsidized price. In 2010 the Department of Agriculture predicted farmers would receive an average of $1.35 per U.S. gallon of cow's milk (35 cents per liter), which is down 30 cents per gallon from 2007 and below the break-even point for many cattle farmers.
Milk is an emulsion or colloid of butterfat globules within a water-based fluid that contains dissolved carbohydrates and protein aggregates with minerals. Because it is produced as a food source for the young, all of its contents provide benefits for growth. The principal requirements are energy (lipids, lactose, and protein), biosynthesis of non-essential amino acids supplied by proteins (essential amino acids and amino groups), essential fatty acids, vitamins and inorganic elements, and water.
Initially milk fat is secreted in the form of a fat globule surrounded by a membrane. Each fat globule is composed almost entirely of triacylglycerols and is surrounded by a membrane consisting of complex lipids such as phospholipids, along with proteins. These act as emulsifiers which keep the individual globules from coalescing and protect the contents of these globules from various enzymes in the fluid portion of the milk. Although 97–98% of lipids are triacylglycerols, small amounts of di- and monoacylglycerols, free cholesterol and cholesterol esters, free fatty acids, and phospholipids are also present. Unlike protein and carbohydrates, fat composition in milk varies widely in the composition due to genetic, lactational, and nutritional factor difference between different species.
Like composition, fat globules vary in size from less than 0.2 to about 15 micrometers in diameter between different species. Diameter may also vary between animals within a species and at different times within a milking of a single animal. In unhomogenized cow's milk, the fat globules have an average diameter of two to four micrometers and with homogenization, average around 0.4 micrometers. The fat-soluble vitamins A, D, E, and K along with essential fatty acids such as linoleic and linolenic acid are found within the milk fat portion of the milk.
Normal bovine milk contains 30–35 grams of protein per liter of which about 80% is arranged in casein micelles. Total proteins in milk represent 3.2% of its composition (nutrition table).
The largest structures in the fluid portion of the milk are "casein micelles": aggregates of several thousand protein molecules with superficial resemblance to a surfactant micelle, bonded with the help of nanometer-scale particles of calcium phosphate. Each casein micelle is roughly spherical and about a tenth of a micrometer across. There are four different types of casein proteins: αs1-, αs2-, β-, and κ-caseins. Most of the casein proteins are bound into the micelles. There are several competing theories regarding the precise structure of the micelles, but they share one important feature: the outermost layer consists of strands of one type of protein, k-casein, reaching out from the body of the micelle into the surrounding fluid. These kappa-casein molecules all have a negative electrical charge and therefore repel each other, keeping the micelles separated under normal conditions and in a stable colloidal suspension in the water-based surrounding fluid.
Milk contains dozens of other types of proteins beside caseins and including enzymes. These other proteins are more water-soluble than caseins and do not form larger structures. Because the proteins remain suspended in whey remaining when caseins coagulate into curds, they are collectively known as whey proteins. Lactoglobulin is the most common whey protein by a large margin. The ratio of caseins to whey proteins varies greatly between species; for example, it is 82:18 in cows and around 32:68 in humans.
|Human||29.7:70.3 – 33.7:66.3|
|Camel||73:27 – 76:24|
|Reindeer||80:20 – 83:17|
Minerals or milk salts, are traditional names for a variety of cations and anions within bovine milk. Calcium, phosphate, magnesium, sodium, potassium, citrate, and chloride are all included as minerals and they typically occur at concentration of 5–40 mM. The milk salts strongly interact with casein, most notably calcium phosphate. It is present in excess and often, much greater excess of solubility of solid calcium phosphate. In addition to calcium, milk is a good source of many other vitamins. Vitamins A, B6, B12, C, D, K, E, thiamine, niacin, biotin, riboflavin, folates, and pantothenic acid are all present in milk.
For many years the most accepted theory of the structure of a micelle was that it was composed of spherical casein aggregates, called submicelles, that were held together by calcium phosphate linkages. However, there are two recent models of the casein micelle that refute the distinct micellular structures within the micelle.
The first theory attributed to de Kruif and Holt, proposes that nanoclusters of calcium phosphate and the phosphopeptide fraction of beta-casein are the centerpiece to micellular structure. Specifically in this view, unstructured proteins organize around the calcium phosphate giving rise to their structure and thus no specific structure is formed.
The second theory proposed by Horne, the growth of calcium phosphate nanoclusters begins the process of micelle formation but is limited by binding phosphopeptide loop regions of the caseins. Once bound, protein-protein interactions are formed and polymerization occurs, in which K-casein is used as an end cap, to form micelles with trapped calcium phosphate nanoclusters.
Some sources indicate that the trapped calcium phosphate is in the form of Ca9(PO4)6; whereas, others say it is similar to the structure of the mineral brushite CaHPO4 -2H2O.
Milk contains several different carbohydrate including lactose, glucose, galactose, and other oligosaccharides. The lactose gives milk its sweet taste and contributes approximately 40% of whole cow's milk's calories. Lactose is a disaccharide composite of two simple sugars, glucose and galactose. Bovine milk averages 4.8% anhydrous lactose, which amounts to about 50% of the total solids of skimmed milk. Levels of lactose are dependent upon the type of milk as other carbohydrates can be present at higher concentrations than lactose in milks.
Both the fat globules and the smaller casein micelles, which are just large enough to deflect light, contribute to the opaque white color of milk. The fat globules contain some yellow-orange carotene, enough in some breeds (such as Guernsey and Jersey cattle) to impart a golden or "creamy" hue to a glass of milk. The riboflavin in the whey portion of milk has a greenish color, which sometimes can be discerned in skimmed milk or whey products. Fat-free skimmed milk has only the casein micelles to scatter light, and they tend to scatter shorter-wavelength blue light more than they do red, giving skimmed milk a bluish tint.
In most Western countries, centralized dairy facilities process milk and products obtained from milk, such as cream, butter, and cheese. In the U.S., these dairies usually are local companies, while in the Southern Hemisphere facilities may be run by large multi-national corporations such as Fonterra.
Pasteurization is used to kill harmful pathogenic bacteria by heating the milk for a short time and then immediately cooling it. Types of pasteurized milk include full cream, reduced fat, skim milk, calcium enriched, flavored, and UHT. The standard high temperature short time (HTST) process of 72 °C for 15 seconds completely kills pathogenic bacteria in milk, rendering it safe to drink for up to three weeks if continually refrigerated. Dairies print best before dates on each container, after which stores remove any unsold milk from their shelves.
A side effect of the heating of pasteurization is that some vitamin and mineral content is lost. Soluble calcium and phosphorus decrease by 5%, thiamin and vitamin B12 by 10%, and vitamin C by 20%. Because losses are small in comparison to the large amount of the two B-vitamins present, milk continues to provide significant amounts of thiamin and vitamin B12. The loss of vitamin C is not nutritionally significant, as milk is not an important dietary source of vitamin C.
Microfiltration is a process that partially replaces pasteurization and produces milk with fewer microorganisms and longer shelf life without a change in the taste of the milk. In this process, cream is separated from the skimmed milk and is pasteurized in the usual way, but the skimmed milk is forced through ceramic microfilters that trap 99.9% of microorganisms in the milk (as compared to 99.999% killing of microorganisms in standard HTST pasteurization). The skimmed milk then is recombined with the pasteurized cream to reconstitute the original milk composition.
Ultrafiltration uses finer filters than microfiltration, which allow lactose and water to pass through while retaining fats, calcium and protein. As with microfiltration, the fat may be removed before filtration and added back in afterwards. Ultrafiltered milk is used is cheesemaking, since it has reduced volume for a given protein content, and is sold directly to consumers as a higher protein, lower sugar content, and creamier alternative to regular milk.
Upon standing for 12 to 24 hours, fresh milk has a tendency to separate into a high-fat cream layer on top of a larger, low-fat milk layer. The cream often is sold as a separate product with its own uses. Today the separation of the cream from the milk usually is accomplished rapidly in centrifugal cream separators. The fat globules rise to the top of a container of milk because fat is less dense than water. The smaller the globules, the more other molecular-level forces prevent this from happening. In fact, the cream rises in cow's milk much more quickly than a simple model would predict: rather than isolated globules, the fat in the milk tends to form into clusters containing about a million globules, held together by a number of minor whey proteins. These clusters rise faster than individual globules can. The fat globules in milk from goats, sheep, and water buffalo do not form clusters as readily and are smaller to begin with, resulting in a slower separation of cream from these milks.
Milk often is homogenized, a treatment that prevents a cream layer from separating out of the milk. The milk is pumped at high pressures through very narrow tubes, breaking up the fat globules through turbulence and cavitation. A greater number of smaller particles possess more total surface area than a smaller number of larger ones, and the original fat globule membranes cannot completely cover them. Casein micelles are attracted to the newly exposed fat surfaces. Nearly one-third of the micelles in the milk end up participating in this new membrane structure. The casein weighs down the globules and interferes with the clustering that accelerated separation. The exposed fat globules are vulnerable to certain enzymes present in milk, which could break down the fats and produce rancid flavors. To prevent this, the enzymes are inactivated by pasteurizing the milk immediately before or during homogenization.
Homogenized milk tastes blander but feels creamier in the mouth than unhomogenized. It is whiter and more resistant to developing off flavors. Creamline (or cream-top) milk is unhomogenized. It may or may not have been pasteurized. Milk that has undergone high-pressure homogenization, sometimes labeled as "ultra-homogenized", has a longer shelf life than milk that has undergone ordinary homogenization at lower pressures.
Ultra Heat Treatment (UHT), is a type of milk processing where all bacteria are destroyed with high heat to extend its shelf life for up to 6 months, as long as the package is not opened. Milk is firstly homogenized and then is heated to 138 degrees Celsius for 1–3 seconds. The milk is immediately cooled down and packed into a sterile container. As a result of this treatment, all the pathogenic bacteria within the milk are destroyed, unlike when the milk is just pasteurised. The milk will now keep for up for 6 months if unopened. UHT milk does not need to be refrigerated until the package is opened, which makes it easier to ship 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 the milk.
The composition of milk differs widely among species. Factors such as the type of protein; the proportion of protein, fat, and sugar; the levels of various vitamins and minerals; and the size of the butterfat globules, and the strength of the curd are among those that may vary. For example:
|----Saturated fatty acids||g||2.4||2.3||3.8||4.2|
|----Monounsaturated fatty acids||g||1.1||0.8||1.5||1.7|
|----Polyunsaturated fatty acids||g||0.1||0.1||0.3||0.2|
|Carbohydrate (i.e. the sugar form of lactose)||g||4.8||4.4||5.1||4.9|
These compositions vary by breed, animal, and point in the lactation period.
|Cow breed||Approximate percentage|
The protein range for these four breeds is 3.3% to 3.9%, while the lactose range is 4.7% to 4.9%.
Milk fat percentages may be manipulated by dairy farmers' stock diet formulation strategies. Mastitis infection can cause fat levels to decline.
|Cow's milk (whole)|
|Nutritional value per 100 g (3.5 oz)|
|Energy||252 kJ (60 kcal)|
|Sugars||5.26 g |
|Aspartic acid||0.237 g|
|Glutamic acid||0.648 g|
|Vitamin A equiv.|
100 mL corresponds to 103 g.
|†Percentages are roughly approximated using US recommendations for adults. |
Source: USDA Nutrient Database
Processed cow's milk was formulated to contain differing amounts of fat during the 1950s. One cup (250 mL) of 2%-fat cow's milk contains 285 mg of calcium, which represents 22% to 29% of the daily recommended intake (DRI) of calcium for an adult. Depending on its age, milk contains 8 grams of protein, and a number of other nutrients (either naturally or through fortification) including:
The amount of calcium from milk that is absorbed by the human body is disputed. Calcium from dairy products has a greater bioavailability than calcium from certain vegetables, such as spinach, that contain high levels of calcium-chelating agents, but a similar or lesser bioavailability than calcium from low-oxalate vegetables such as kale, broccoli, or other vegetables in the genus Brassica.
Milk as a calcium source has been questioned in media, but scientific research is lacking to support the hypothesis of acidosis induced by milk. The hypothesis in question being that acidosis would lead to leaching of calcium storages in bones to neutralize pH levels (also known as acid-ash hypothesis). Research has found no link between metabolic acidosis and consumption of milk.
The U.S. federal government document Dietary Guidelines for Americans, 2010 recommends consumption of three glasses of fat-free or low-fat milk for adults and children 9 and older (less for younger children) per day. This recommendation is disputed by some health researchers who call for more study of the issue, given that there are other sources for calcium and vitamin D. The researchers also claim that the recommendations have been unduly influenced by the American dairy industry, and that whole milk may be better for health due to its increased ability to satiate hunger.
A 2008 review found evidence suggesting that consumption of milk is effective at promoting muscle growth. Some studies have suggested that conjugated linoleic acid, which can be found in dairy products, is an effective supplement for reducing body fat. With regards to the claim of milk promoting stronger bones, there has been no association between milk consumption or excess calcium intake and a reduced risk of bone fractures.
In 2011, The Journal of Bone and Mineral Research published a meta-analysis examining whether milk consumption might protect against hip fracture in middle-aged and older adults. Studies could find no association between drinking milk and lower rates of fractures. In 2014, JAMA Pediatrics published a report after monitoring almost 100,000 men and women for more than two decades. Subjects were asked to report on how much milk they had consumed as teenagers, and were followed to see if there was any association with a reduced chance of hip fractures later in life. No correlation was found. A study published in The BMJ that followed more than 45,000 men and 61,000 women in Sweden age 39 and older had similar results. Milk consumption in adults was associated with no protection for men, and an increased risk of fractures in women. The risk of any bone fracture increased 16% in women who drank three or more glasses daily, and the risk of a broken hip increased 60%. It was also associated with an increased risk of death in both sexes.
Milk and dairy products have the potential for causing serious infection in newborn infants. Unpasteurized milk and cheeses can promote the growth of Listeria bacteria. Listeria monocytogenes can also cause serious infection in an infant and pregnant woman and can be transmitted to her infant in utero or after birth. The infection has the potential of seriously harming or even causing the death of a preterm infant, an infant of low or very low birth weight, or an infant with an immune system defect or a congenital defect of the immune system. The presence of this pathogen can sometimes be determined by the symptoms that appear as a gastrointestinal illness in the mother. The mother can also acquire infection from ingesting food that contains other animal products such as, hot dogs, delicatessen meats, and cheese.
Lactose, the disaccharide sugar component of all milk, must be cleaved in the small intestine by the enzyme lactase, in order for its constituents, galactose and glucose, to be absorbed. Lactose intolerance is a condition in which people have symptoms due to not enough of the enzyme lactase in the small intestines. Those affected vary in the amount of lactose they can tolerate before symptoms develop. These may include abdominal pain, bloating, diarrhea, gas, and nausea. Severity depends on the amount a person eats or drinks. Those affected are usually able to drink at least one cup of milk without developing significant symptoms, with greater amounts tolerated if drunk with a meal 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 decline as people age. Secondary lactose intolerance is due to injury to the small intestine such as from infection, celiac disease, inflammatory bowel disease, or other diseases. Developmental lactose intolerance may occur in premature babies and usually improves over a short period of time. Congenital lactose intolerance is an extremely 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 a milk allergy.
The number of people with lactose intolerance is unknown. Some human populations have developed lactase persistence, in which lactase production continues into adulthood probably as a response to the benefits of being able to digest milk from farm animals. The percentage of the population that has a decrease in lactase as they age is less than 10% in Northern Europe and as high as 95% in parts of Asia and Africa.
Some studies suggest that milk consumption may increase the risk of suffering from certain health problems. Cow's milk allergy (CMA) is an immunologically mediated adverse reaction, rarely fatal, to one or more cow's milk proteins. Milk from any mammal contains amino acids and microRNA which influence the drinker's metabolism and growth; this "programming" is beneficial for milk's natural consumers, namely infants of the same species as the milk producer, but post-infancy and trans-species milk consumption affects the mTORC1 metabolic pathway and may promote diseases of civilization such as obesity and diabetes.
Milk contains exogenous opioid peptides called exorphins which include opioid food peptides like Gluten exorphin and opioid food peptides. Exorphins mimic the actions of endorphines because they bind to the same opioid receptors in the brain. The exorphin in milk is called casein, a substance that breaks down in the human stomach to produce the opioid peptide casomorphin. In the early 1990s it was hypothesized that casomorphin can cause or aggravate autism spectrum disorders, and casein-free diets are widely promoted. Studies supporting these claims have had significant flaws, and the data are inadequate to guide autism treatment recommendations.
The most recent assessment by the World Cancer Research Fund and the American Institute for Cancer Research found that most individual epidemiological studies showed increased risk of prostate cancer with increased intake of milk or dairy products. "Meta-analysis of cohort data produced evidence of a clear dose-response relationship between advanced/aggressive cancer risk with milk intake, and between all prostate cancer risk and milk and dairy products." Possible mechanisms proposed included inhibition of the conversion of vitamin D to its active metabolite, 1,25- dihydroxy vitamin D3 by calcium (which some evidence suggests increases cell proliferation in the prostate), and elevation of levels of insulin-like growth factor-1 (IGF-1). Several sources suggest a correlation between high calcium intake from milk, in particular, and prostate cancer, consistent with a calcium/vitamin D based mechanism. Overall, the WCRF/AICR panel concluded that "The evidence is inconsistent from both cohort and case-control studies. There is limited evidence suggesting that milk and dairy products are a cause of prostate cancer."
Milk must be offered at every meal if a United States school district wishes to get reimbursement from the federal government. A quarter of the largest school districts in the U.S. offer rice or soy milk and almost 17% of all U.S. school districts offer lactose-free milk. Of the milk served in U.S. school cafeterias, 71% is flavored, causing some school districts to propose a ban because flavored milk has added sugars. (Though some flavored milk products use artificial sweeteners instead.) The Boulder, Colorado, school district banned flavored milk in 2009 and instead installed a dispenser that keeps the milk colder.
The mammary gland is thought to have derived from apocrine skin glands. It has been suggested that the original function of lactation (milk production) was keeping eggs moist. Much of the argument is based on monotremes (egg-laying mammals). The original adaptive significance of milk secretions may have been nutrition or immunological protection. This secretion gradually became more copious and accrued nutritional complexity over evolutionary time.
Since November 1993, recombinant bovine somatotropin (rbST), also called rBGH, has been sold to dairy farmers with FDA approval. Cows produce bovine growth hormone naturally, but some producers administer an additional recombinant version of BGH which is produced through genetically engineered E. coli to increase milk production. Bovine growth hormone also stimulates liver production of insulin-like growth factor 1 (IGF1). The U.S. 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 at the amounts present.
Milk from cows given rBST may be sold in the United States, and the FDA stated that no significant difference has been shown between milk derived from rBST-treated and that from non-rBST-treated cows. Milk that advertises that it comes from cows not treated with rBST, is required to state this finding on its label.
Cows receiving rBGH supplements may more frequently contract an udder infection known as mastitis. Problems with mastitis have led to Canada, Australia, New Zealand, and Japan banning milk from rBST treated cows. Mastitis, among other diseases, may be responsible for the fact that levels of white blood cells in milk vary naturally.
rBGH is also banned in the European Union, for reasons of animal welfare.
Vegans and some other vegetarians do not consume milk for reasons mostly related to animal rights and environmental concerns. They may object to features of dairy farming including the necessity of keeping dairy cows pregnant, the killing of almost all the male offspring of dairy cows (either by disposal soon after birth, for veal production, or for beef), the routine separation of mother and calf soon after birth, other perceived inhumane treatment of dairy cattle, and culling of cows after their productive lives.
Some have criticized the American government's promotion of milk consumption. Their main concern is the financial interest that the American government has taken in the dairy industry, promoting milk as the best source of calcium. All United States schools that are a part of the federally funded National School Lunch Act are required by the federal government to provide milk for all students. The Office of Dietary Supplements recommends that healthy adults between ages 19 and 50 get about 1,000 mg of calcium per day.
Milk production is also resource intensive. On a global weighted average, for the production of a given volume of milk, a thousand times as much water has to be used.
Milk products are sold in a number of varieties based on types/degrees of:
Milk preserved by the UHT process does not need to be refrigerated before opening and has a much longer shelf life (six months) than milk in ordinary packaging. It is typically sold unrefrigerated in the UK, U.S., Europe, Latin America, and Australia.
Lactose-free milk can be produced by passing milk over lactase enzyme bound to an inert carrier. Once the molecule is cleaved, there are no lactose ill effects. Forms are available with reduced amounts of lactose (typically 30% of normal), and alternatively with nearly 0%. The only noticeable difference from regular milk is a slightly sweeter taste due to the generation of glucose by lactose cleavage. It does not, however, contain more glucose, and is nutritionally identical to regular milk.
Finland, where approximately 17% of the Finnish-speaking population has hypolactasia, has had "HYLA" (acronym for hydrolysed lactose) products available for many years. Lactose of low-lactose level cow's milk products, ranging from ice cream to cheese, is enzymatically hydrolysed into glucose and galactose. The ultra-pasteurization process, combined with aseptic packaging, ensures a long shelf life. In 2001, Valio launched a lactose-free milk drink that is not sweet like HYLA milk but has the fresh taste of ordinary milk. Valio patented the chromatographic separation method to remove lactose. Valio also markets these products in Sweden, Estonia, Belgium, and the United States, where the company says ultrafiltration is used.
To aid digestion in those with lactose intolerance, milk with added bacterial cultures such as Lactobacillus acidophilus ("acidophilus milk") and bifidobacteria ("a/B milk") is available in some areas. Another milk with Lactococcus lactis bacteria cultures ("cultured buttermilk") often is used in cooking to replace the traditional use of naturally soured milk, which has become rare due to the ubiquity of pasteurization, which also kills the naturally occurring Lactococcus bacteria.
Lactose-free and lactose-reduced milk can also be produced via ultra filtration, which removes smaller molecules such as lactose and water while leaving calcium and proteins behind. Milk produced via these methods has a lower sugar content than regular milk.
Reduced-fat milks often have added vitamin A palmitate to compensate for the loss of the vitamin during fat removal; in the United States this results in reduced fat milks having a higher vitamin A content than whole milk.
Milk often has flavoring added to it for better taste or as a means of improving sales. Chocolate milk has been sold for many years and has been followed more recently by strawberry milk and others. Some nutritionists have criticized flavored milk for adding sugar, usually in the form of high-fructose corn syrup, to the diets of children who are already commonly obese in the U.S.
Due to the short shelf life of normal milk, it used to be delivered to households daily in many countries; however, improved refrigeration at home, changing food shopping patterns because of supermarkets, and the higher cost of home delivery mean that daily deliveries by a milkman are no longer available in most countries.
In Australia and New Zealand, prior to metrication, milk was generally distributed in 1 pint (568 mL) glass bottles. In Australia and Ireland there was a government funded "free milk for school children" program, and milk was distributed at morning recess in 1/3 pint bottles. With the conversion to metric measures, the milk industry were concerned that the replacement of the pint bottles with 500 mL bottles would result in a 13.6% drop in milk consumption; hence, all pint bottles were recalled and replaced by 600 mL bottles. With time, due to the steadily increasing cost of collecting, transporting, storing and cleaning glass bottles, they were replaced by cardboard cartons. A number of designs were used, including a tetrahedron which could be close-packed without waste space, and could not be knocked over accidentally. (slogan: No more crying over spilt milk.) However, the industry eventually settled on a design similar to that used in the United States.
Milk is now available in a variety of sizes in paperboard milk cartons (250 mL, 375 mL, 600 mL, 1 liter and 1.5 liters) and plastic bottles (1, 2 and 3 liters). A significant addition to the marketplace has been "long-life" milk (UHT), generally available in 1 and 2 liter rectangular cardboard cartons. In urban and suburban areas where there is sufficient demand, home delivery is still available, though in suburban areas this is often 3 times per week rather than daily. Another significant and popular addition to the marketplace has been flavored milks – for example, as mentioned above, Farmers Union Iced Coffee outsells Coca-Cola in South Australia.
In rural India, milk is home delivered, daily, by local milkmen carrying bulk quantities in a metal container, usually on a bicycle. In other parts of metropolitan India, milk is usually bought or delivered in plastic bags or cartons via shops or supermarkets.
The current milk chain flow in India is from milk producer to milk collection agent. Then it is transported to a milk chilling center and bulk transported to the processing plant, then to the sales agent and finally to the consumer.
A 2011 survey by the Food Safety and Standards Authority of India found that nearly 70% of samples had not conformed to the standards set for milk. The study found that due to lack of hygiene and sanitation in milk handling and packaging, detergents (used during cleaning operations) were not washed properly and found their way into the milk. About 8% of samples in the survey were found to have detergents, which are hazardous to health.
In Pakistan, milk is supplied in jugs. Milk has been a staple food, especially among the pastoral tribes in this country.
Since the late 1990s, milk-buying patterns have changed drastically in the UK. The classic milkman, who travels his local milk round (route) using a milk float (often battery powered) during the early hours and delivers milk in 1 pint glass bottles with aluminium foil tops directly to households, has almost disappeared. Two of the main reasons for the decline of UK home deliveries by milkmen are household refrigerators (which lessen the need for daily milk deliveries) and private car usage (which has increased supermarket shopping). Another factor is that it is cheaper to purchase milk from a supermarket than from home delivery. In 1996, more than 2.5 billion liters of milk were still being delivered by milkmen, but by 2006 only 637 million liters (13% of milk consumed) was delivered by some 9,500 milkmen. By 2010, the estimated number of milkmen had dropped to 6,000. Assuming that delivery per milkman is the same as it was in 2006, this means milkmen deliveries now only account for 6–7% of all milk consumed by UK households (6.7 billion liters in 2008/2009).
Almost 95% of all milk in the UK is thus sold in shops today, most of it in plastic bottles of various sizes, but some also in milk cartons. Milk is hardly ever sold in glass bottles in UK shops.
In the United States, glass milk bottles have been replaced mostly with milk cartons and plastic jugs. Gallons of milk are almost always sold in jugs, while half gallons and quarts may be found in both paper cartons and plastic jugs, and smaller sizes are almost always in cartons.
The "half pint" (237 mL, 5⁄12 imp pt) milk carton is the traditional unit as a component of school lunches, though some companies have replaced that unit size with a plastic bottle, which is also available at retail in 6- and 12-pack size.
Glass milk bottles are now rare. Most people purchase milk in bags, plastic bottles, or plastic-coated paper cartons. Ultraviolet (UV) light from fluorescent lighting can alter the flavor of milk, so many companies that once distributed milk in transparent or highly translucent containers are now using thicker materials that block the UV light. Milk comes in a variety of containers with local variants:
Practically everywhere, condensed milk and evaporated milk are distributed in metal cans, 250 and 125 mL paper containers and 100 and 200 mL squeeze tubes, and powdered milk (skim and whole) is distributed in boxes or bags.
When raw milk is left standing for a while, it turns "sour". This is the result of fermentation, where lactic acid bacteria ferment the lactose in the milk into lactic acid. Prolonged fermentation may render the milk unpleasant to consume. This fermentation process is exploited by the introduction of bacterial cultures (e.g. Lactobacilli sp., Streptococcus sp., Leuconostoc sp., etc.) to produce a variety of fermented milk products. The reduced pH from lactic acid accumulation denatures proteins and causes the milk to undergo a variety of different transformations in appearance and texture, ranging from an aggregate to smooth consistency. Some of these products include sour cream, yogurt, cheese, buttermilk, viili, kefir, and kumis. See Dairy product for more information.
Pasteurization of cow's milk initially destroys any potential pathogens and increases the shelf life, but eventually results in spoilage that makes it unsuitable for consumption. This causes it to assume an unpleasant odor, and the milk is deemed non-consumable due to unpleasant taste and an increased risk of food poisoning. In raw milk, the presence of lactic acid-producing bacteria, under suitable conditions, ferments the lactose present to lactic acid. The increasing acidity in turn prevents the growth of other organisms, or slows their growth significantly. During pasteurization, however, these lactic acid bacteria are mostly destroyed.
In order to prevent spoilage, milk can be kept refrigerated and stored between 1 and 4 °C (34 and 39 °F) in bulk tanks. Most milk is pasteurized by heating briefly and then refrigerated to allow transport from factory farms to local markets. The spoilage of milk can be forestalled by using ultra-high temperature (UHT) treatment. Milk so treated can be stored unrefrigerated for several months until opened but has a characteristic "cooked" taste. Condensed milk, made by removing most of the water, can be stored in cans for many years, unrefrigerated, as can evaporated milk. The most durable form of milk is powdered milk, which is produced from milk by removing almost all water. The moisture content is usually less than 5% in both drum- and spray-dried powdered milk.
Freezing of milk can cause fat globule aggregation upon thawing, resulting in milky layers and butterfat lumps. These can be dispersed again by warming and stirring the milk. It can change the taste by destruction of milk-fat globule membranes, releasing oxidized flavors.
Milk is used to make yogurt, cheese, ice milk, pudding, hot chocolate and french toast. Milk is often added to dry breakfast cereal, porridge and granola. Milk is often served in coffee and tea. Steamed milk is used to prepare espresso-based drinks such as cafe latte.
The importance of milk in human culture is attested to by the numerous expressions embedded in our languages, for example, "the milk of human kindness", the expression "there's no use crying over spilt milk" (which means don't "be unhappy about what cannot be undone"), "don't milk the ram" (this means "to do or attempt something futile") and "Why buy a cow when you can get milk for free?" (which means "why pay for something that you can get for free otherwise").
In Greek mythology, the Milky Way was formed after the trickster god Hermes suckled the infant Heracles at the breast of Hera, the queen of the gods, while she was asleep. When Hera awoke, she tore Heracles away from her breast and splattered her breast milk across the heavens. In another version of the story, Athena, the patron goddess of heroes, tricked Hera into suckling Heracles voluntarily, but he bit her nipple so hard that she flung him away, spraying milk everywhere.
In many African and Asian countries, butter is traditionally made from fermented milk rather than cream. It can take several hours of churning to produce workable butter grains from fermented milk.
Holy books have also mentioned milk. The Bible contains references to the "Land of Milk and Honey." In the Qur'an, there is a request to wonder on milk as follows: "And surely in the livestock there is a lesson for you, We give you to drink of that which is in their bellies from the midst of digested food and blood, pure milk palatable for the drinkers" (16-The Honeybee, 66). The Ramadan fast is traditionally broken with a glass of milk and dates.
Abhisheka is conducted by Hindu and Jain priests, by pouring libations on the image of a deity being worshipped, amidst the chanting of mantras. Usually offerings such as milk, yogurt, ghee, honey may be poured among other offerings depending on the type of abhishekam being performed.
A milksop is an "effeminate spiritless man," an expression which is attested to in the late 14th century. Milk toast is a dish consisting of milk and toast. Its soft blandness served as inspiration for the name of the timid and ineffectual comic strip character Caspar Milquetoast, drawn by H. T. Webster from 1924 to 1952. Thus, the term "milquetoast" entered the language as the label for a timid, shrinking, apologetic person. Milk toast also appeared in Disney's Follow Me Boys as an undesirable breakfast for the aging main character Lem Siddons.
To "milk" someone, in the vernacular of many English-speaking countries, is to take advantage of the person, by analogy to the way a farmer "milks" a cow and takes its milk. The word "milk" has had many slang meanings over time. In the 19th century, milk was used to describe a cheap and very poisonous alcoholic drink made from methylated spirits (methanol) mixed with water. The word was also used to mean defraud, to be idle, to intercept telegrams addressed to someone else, and a weakling or "milksop." In the mid-1930s, the word was used in Australia meaning to siphon gas from a car.
Besides serving as a beverage or source of food, milk has been described as used by farmers and gardeners as an organic fungicide and fertilizer, however, its effectiveness is debated. Diluted milk solutions have been demonstrated to provide an effective method of preventing powdery mildew on grape vines, while showing it is unlikely to harm the plant.
A remarkable adaptation can be found in the crop of pigeons. During the breeding season the crop produces a yellow-white fat-rich secretion known as crop milk that is used to feed the nestlings. … The crop milk resembles strongly the milk produced by mammals, except for the fact that carbohydrates and calcium are missing in crop milk.
Breast milk is the milk produced by the breasts (or mammary glands) of a human female to feed a child. Milk is the primary source of nutrition for newborns before they are able to eat and digest other foods; older infants and toddlers may continue to be breastfed, in combination with other foods from six months of age when solid foods should be introduced.Breastfeeding
Breastfeeding, also known as nursing, is the feeding of babies and young children with milk from a woman's breast. Health professionals recommend that breastfeeding begin within the first hour of a baby's life and continue as often and as much as the baby wants. During the first few weeks of life babies may nurse roughly every two to three hours, and the duration of a feeding is usually ten to fifteen minutes on each breast. Older children feed less often. Mothers may pump milk so that it can be used later when breastfeeding is not possible. Breastfeeding has a number of benefits to both mother and baby, which infant formula lacks.Deaths of an estimated 820,000 children under the age of five could be prevented globally every year with increased breastfeeding. Breastfeeding decreases the risk of respiratory tract infections and diarrhea, both in developing and developed countries. Other benefits include lower risks of asthma, food allergies, type 1 diabetes, and leukemia. Breastfeeding may also improve cognitive development and decrease the risk of obesity in adulthood. Mothers may feel pressure to breastfeed, but in the developed world children generally grow up normally when bottle fed.Benefits for the mother include less blood loss following delivery, better uterus shrinkage, and decreased postpartum depression. Breastfeeding delays the return of menstruation and fertility, a phenomenon known as lactational amenorrhea. Long term benefits for the mother include decreased risk of breast cancer, cardiovascular disease, and rheumatoid arthritis. Breastfeeding is less expensive than infant formula.Health organizations, including the World Health Organization (WHO), recommend breastfeeding exclusively for six months. This means that no other foods or drinks other than possibly vitamin D are typically given. After the introduction of foods at six months of age, recommendations include continued breastfeeding until one to two years of age or more. Globally about 38% of infants are only breastfed during their first six months of life. In the United States in 2015, 83% of women begin breastfeeding and 58% were still breastfeeding at 6 months, although only 25% exclusively. Medical conditions that do not allow breastfeeding are rare. Mothers who take certain recreational drugs and medications should not breastfeed. Smoking, limited amounts of alcohol, or coffee are not reasons to avoid breastfeeding.Bubble tea
Bubble tea (also known as pearl milk tea, bubble milk tea, or boba) (Chinese: 波霸奶茶; pinyin: bōbà nǎichá, with tapioca balls it is 珍珠奶茶; zhēnzhū nǎichá) is a Taiwanese tea-based drink invented in Tainan and Taichung in the 1980s. Recipes contain tea of some kind, flavors of milk, as well as sugar (optional). Toppings, such as chewy tapioca balls (also known as pearls or boba), popping boba, fruit jelly, grass jelly, agar jelly, and puddings are often added. Ice-blended versions are frozen and put into a blender, resulting in a slushy consistency. There are many varieties of the drink with a wide range of flavors. The two most popular varieties are black pearl milk tea and green pearl milk tea.Cappuccino
A cappuccino ( (listen); Italian pronunciation: [kapputˈtʃiːno] Italian plural cappuccini) is an espresso-based coffee drink that originated in Italy, and is traditionally prepared with steamed milk foam (microfoam).
Variations of the drink involve the use of cream instead of milk, and flavoring with cinnamon or chocolate powder. It is typically smaller in volume than a caffè latte, with a thicker layer of microfoam.
The name comes from the Capuchin friars, referring to the colour of their habits, and in this context referring to the colour of the beverage when milk is added in small portion to dark, brewed coffee (today mostly espresso). The physical appearance of a modern cappuccino with espresso créma and steamed milk is a result of a long evolution of the drink.
The Viennese bestowed the name "Kapuziner", possibly in the 18th century, on a version that included whipped cream and spices of unknown origin. The Italian cappuccino was unknown outside Italy until the 1930s, and seems to be born out of Viennese-style cafés in Trieste and other cities in the former Austria in the first decades of the 20th century. The drink has since spread worldwide and can be found at a number of establishments.Cheese
Cheese is a dairy product derived from milk that is produced in a wide range of flavors, textures, and forms by coagulation of the milk protein casein. It comprises proteins and fat from milk, usually the milk of cows, buffalo, goats, or sheep. During production, the milk is usually acidified, and adding the enzyme rennet causes coagulation. The solids are separated and pressed into final form. Some cheeses have molds on the rind, the outer layer, or throughout. Most cheeses melt at cooking temperature.
Over a thousand types of cheese from various countries are produced. Their styles, textures and flavors depend on the origin of the milk (including the animal's diet), whether they have been pasteurized, the butterfat content, the bacteria and mold, the processing, and aging. Herbs, spices, or wood smoke may be used as flavoring agents. The yellow to red color of many cheeses, such as Red Leicester, is produced by adding annatto. Other ingredients may be added to some cheeses, such as black pepper, garlic, chives or cranberries.
For a few cheeses, the milk is curdled by adding acids such as vinegar or lemon juice. Most cheeses are acidified to a lesser degree by bacteria, which turn milk sugars into lactic acid, then the addition of rennet completes the curdling. Vegetarian alternatives to rennet are available; most are produced by fermentation of the fungus Mucor miehei, but others have been extracted from various species of the Cynara thistle family. Cheesemakers near a dairy region may benefit from fresher, lower-priced milk, and lower shipping costs.
Cheese is valued for its portability, long life, and high content of fat, protein, calcium, and phosphorus. Cheese is more compact and has a longer shelf life than milk, although how long a cheese will keep depends on the type of cheese; labels on packets of cheese often claim that a cheese should be consumed within three to five days of opening. Generally speaking, hard cheeses, such as Parmesan last longer than soft cheeses, such as Brie or goat's milk cheese. The long storage life of some cheeses, especially when encased in a protective rind, allows selling when markets are favorable.
There is some debate as to the best way to store cheese, but some experts say that wrapping it in cheese paper provides optimal results. Cheese paper is coated in a porous plastic on the inside, and the outside has a layer of wax. This specific combination of plastic on the inside and wax on the outside protects the cheese by allowing condensation on the cheese to be wicked away while preventing moisture from within the cheese escaping.A specialist seller of cheese is sometimes known as a cheesemonger. Becoming an expert in this field requires some formal education and years of tasting and hands-on experience, much like becoming an expert in wine or cuisine. The cheesemonger is responsible for all aspects of the cheese inventory: selecting the cheese menu, purchasing, receiving, storage, and ripening.Coconut milk
Coconut milk is an opaque milky white liquid extracted from the grated pulp of mature coconuts. The opacity and rich taste of coconut milk are due to its high oil content, most of which is saturated fat. Coconut milk is a traditional food ingredient used in Southeast Asia, Oceania, South Asia, and East Africa. It is also used for cooking in the Caribbean, tropical Latin America, and West Africa, where coconuts were introduced during the colonial era.
Coconut milk is differentiated into subtypes based on fat content. They can be generalized to coconut cream (or thick coconut milk) with the highest amount of fat; coconut milk (or thin coconut milk) with a maximum of around 20% fat; and coconut skim milk with negligible amounts of fat. These terminologies are not always followed in commercial coconut milk sold in western countries.Coconut milk can also be used to produce milk substitutes (differentiated as "coconut milk beverages"). These products are not the same as regular coconut milk products which are meant for cooking, not drinking. A sweetened processed coconut milk product from Puerto Rico is also known as cream of coconut. It is used in many desserts and beverages like the piña colada, though it should not be confused with coconut cream.Dairy
A dairy is a business enterprise established for the harvesting or processing (or both) of animal milk – mostly from cows or goats, but also from buffaloes, sheep, horses, or camels – for human consumption. A dairy is typically located on a dedicated dairy farm or in a section of a multi-purpose farm (mixed farm) that is concerned with the harvesting of milk.
Terminology differs between countries. For example, in the United States, an entire dairy farm is commonly called a "dairy". The building or farm area where milk is harvested from the cow is often called a "milking parlor" or "parlor". Except in the case of smaller dairies, where cows are often put on pasture, and usually milked in "stanchion barns". The farm area where milk is stored in bulk tanks is known as the farm's "milk house". Milk is then hauled (usually by truck) to a "dairy plant" = also referred to as a "dairy" - where raw milk is further processed and prepared for commercial sale of dairy products. In New Zealand, farm areas for milk harvesting are also called "milking parlours", and are historically known as "milking sheds". As in the United States, sometimes milking sheds are referred to by their type, such as "herring bone shed" or "pit parlour". Parlour design has evolved from simple barns or sheds to large rotary structures in which the workflow (throughput of cows) is very efficiently handled. In some countries, especially those with small numbers of animals being milked, the farm may perform the functions of a dairy plant, processing their own milk into salable dairy products, such as butter, cheese, or yogurt. This on-site processing is a traditional method of producing specialist milk products, common in Europe.
In the United States a dairy can also be a place that processes, distributes and sells dairy products, or a room, building or establishment where milk is stored and processed into milk products, such as butter or cheese. In New Zealand English the singular use of the word dairy almost exclusively refers to a corner shop, or superette. This usage is historical as such shops were a common place for the public to buy milk products.
As an attributive, the word dairy refers to milk-based products, derivatives and processes, and the animals and workers involved in their production: for example dairy cattle, dairy goat. A dairy farm produces milk and a dairy factory processes it into a variety of dairy products. These establishments constitute the global dairy industry, a component of the food industry.Dairy product
Dairy products, milk products or lacticinia are a type of food produced from or containing the milk of mammals. They are primarily produced from mammals such as cattle, water buffaloes, goats, sheep, camels and humans. Dairy products include food items such as yogurt, cheese and butter. A facility that produces dairy products is known as a dairy, or dairy factory. Dairy products are consumed worldwide, with the exception of most of East and Southeast Asia and parts of central Africa.Goat
The domestic goat or simply goat (Capra aegagrus hircus) is a subspecies of C. aegagrus domesticated from the wild goat of Southwest Asia and Eastern Europe. The goat is a member of the animal family Bovidae and the goat—antelope subfamily Caprinae, meaning it is closely related to the sheep. There are over 300 distinct breeds of goat. Goats are one of the oldest domesticated species of animal, and have been used for milk, meat, fur, and skins across much of the world. Milk from goats is often turned into goat cheese.
Female goats are referred to as does or nannies, intact males are called bucks or billies and juvenile goats of both sexes are called kids. Castrated males are called wethers. While the words hircine and caprine both refer to anything having a goat-like quality, hircine is used most often to emphasize the distinct smell of domestic goats.
In 2011, there were more than 924 million goats living in the world, according to the UN Food and Agriculture Organization.Harvey Milk
Harvey Bernard Milk (May 22, 1930 – November 27, 1978) was an American politician and the first openly gay elected official in the history of California, where he was elected to the San Francisco Board of Supervisors. Although he was the most pro-LGBT politician in the United States at the time, politics and activism were not his early interests; he was neither open about his sexuality nor civically active until he was 40, after his experiences in the counterculture movement of the 1960s.
In 1972, Milk moved from New York City to the Castro District of San Francisco amid a migration of gay and bisexual men. He took advantage of the growing political and economic power of the neighborhood to promote his interests and unsuccessfully ran three times for political office. Milk's theatrical campaigns earned him increasing popularity, and in 1977 he won a seat as a city supervisor. His election was made possible by a key component of a shift in San Francisco politics.
Milk served almost eleven months in office, during which he sponsored a bill banning discrimination in public accommodations, housing, and employment on the basis of sexual orientation. The Supervisors passed the bill by a vote of 11-1 and was signed into law by Mayor Moscone. On November 27, 1978, Milk and Mayor George Moscone were assassinated by Dan White, who was another city supervisor. White had recently resigned to pursue a private business enterprise, but that endeavor eventually failed and he sought to get his old job back. White was sentenced to seven years in prison for manslaughter, which was later reduced to five years. He was released in 1983 and committed suicide by carbon monoxide inhalation two years later.
Despite his short career in politics, Milk became an icon in San Francisco and a martyr in the gay community. In 2002, Milk was called "the most famous and most significantly open LGBT official ever elected in the United States". Anne Kronenberg, his final campaign manager, wrote of him: "What set Harvey apart from you or me was that he was a visionary. He imagined a righteous world inside his head and then he set about to create it for real, for all of us." Milk was posthumously awarded the Presidential Medal of Freedom in 2009.Ice cream
Ice cream (derived from earlier iced cream or cream ice) is a sweetened frozen food typically eaten as a snack or dessert. It may be made from dairy milk or cream, or soy, cashew, coconut or almondmilk, and is flavored with a sweetener, either sugar or an alternative, and any spice, such as cocoa or vanilla. Colourings are usually added, in addition to stabilizers. The mixture is stirred to incorporate air spaces and cooled below the freezing point of water to prevent detectable ice crystals from forming. The result is a smooth, semi-solid foam that is solid at very low temperatures (below 2 °C or 35 °F). It becomes more malleable as its temperature increases.
The meaning of the name "ice cream" varies from one country to another. Terms such as "frozen custard," "frozen yogurt," "sorbet," "gelato," and others are used to distinguish different varieties and styles. In some countries, such as the United States, "ice cream" applies only to a specific variety, and most governments regulate the commercial use of the various terms according to the relative quantities of the main ingredients, notably the amount of cream. Products that do not meet the criteria to be called ice cream are sometimes labelled "frozen dessert" instead. In other countries, such as Italy and Argentina, one word is used for all variants. Analogues made from dairy alternatives, such as goat's or sheep's milk, or milk substitutes (e.g., soy milk or tofu), are available for those who are lactose intolerant, allergic to dairy protein, or vegan.
Ice cream may be served in dishes, for eating with a spoon, or licked from edible cones. Ice cream may be served with other desserts, such as apple pie, or as an ingredient in ice cream floats, sundaes, milkshakes, ice cream cakes and even baked items, such as Baked Alaska.Josh Brolin
Joshua James Brolin (; born February 12, 1968) is an American actor. Brolin is known for his wide range of films such as The Goonies (1985), Mimic (1997), Hollow Man (2000), Grindhouse (2007), No Country for Old Men (2007), American Gangster (2007), W. (2008), Milk (2008), True Grit (2010), Men in Black 3 (2012), Inherent Vice (2014), Sicario (2015), Hail, Caesar! (2016), Deadpool 2 (2018), Avengers: Infinity War (2018), and Avengers: Endgame (2019).
Brolin began portraying the role of Marvel Comics super villain Thanos in the Marvel Cinematic Universe, making his first appearance in Guardians of the Galaxy (2014). He appears in another mid-credits scene in Avengers: Age of Ultron (2015). He then went on to become the primary antagonist in Avengers: Infinity War (2018), before reprising the role in Avengers: Endgame (2019).
Brolin has been nominated for the Academy Award, Screen Actors Guild Award, Critics' Choice Movie Awards, Independent Spirit Awards, and an MTV award.Lactose intolerance
Lactose intolerance is a condition in which people have symptoms due to the decreased ability to digest lactose, a sugar found in dairy products. Those affected vary in the amount of lactose they can tolerate before symptoms develop. Symptoms may include abdominal pain, bloating, diarrhea, gas, and nausea. These symptoms typically start thirty minutes to two hours after eating or drinking milk-based food. Severity typically depends on the amount a person eats or drinks. Lactose intolerance does not cause damage to the gastrointestinal tract.Lactose intolerance is due to the lack of enzyme lactase in the small intestines to break lactose down into glucose and galactose. There are four types: primary, secondary, developmental, and congenital. Primary lactose intolerance occurs as the amount of lactase declines as people age. Secondary lactose intolerance is due to injury to the small intestine such as from infection, celiac disease, inflammatory bowel disease, or other diseases. Developmental lactose intolerance may occur in premature babies and usually improves over a short period of time. Congenital lactose intolerance is an extremely rare genetic disorder in which little or no lactase is made from birth.Diagnosis may be confirmed if symptoms resolve following eliminating lactose from the diet. Other supporting tests include a hydrogen breath test and a stool acidity test. Other conditions that may produce similar symptoms include irritable bowel syndrome, celiac disease, and inflammatory bowel disease. Lactose intolerance is different from a milk allergy. Management is typically by decreasing the amount of lactose in the diet, taking lactase supplements, or treating the underlying disease. People are usually able to drink at least one cup of milk per sitting without developing significant symptoms, with greater amounts tolerated if drunk with a meal or throughout the day.The exact number of adults with lactose intolerance is unknown. One estimate puts the average at 65% of the global population. Rates of lactose intolerance vary between regions, from less than 10% in Northern Europe to as high as 95% in parts of Asia and Africa. Onset is typically in late childhood or early adulthood. The ability to digest lactose into adulthood evolved in several human populations independently, probably as an adaptation to the domestication of dairy animals 10,000 years ago.Margaret Thatcher
Margaret Hilda Thatcher, Baroness Thatcher, (née Roberts; 13 October 1925 – 8 April 2013) was a British stateswoman who served as Prime Minister of the United Kingdom from 1979 to 1990 and Leader of the Conservative Party from 1975 to 1990. She was the longest-serving British prime minister of the 20th century and the first woman to hold that office. A Soviet journalist dubbed her "The 'Iron Lady'", a nickname that became associated with her uncompromising politics and leadership style. As Prime Minister, she implemented policies known as Thatcherism.
She studied chemistry at Somerville College, Oxford, and worked briefly as a research chemist, before becoming a barrister. Thatcher was elected Member of Parliament for Finchley in 1959. Edward Heath appointed her Secretary of State for Education and Science in his Conservative government. In 1975, Thatcher defeated Heath in the Conservative Party leadership election to become Leader of the Opposition, the first woman to lead a major political party in the United Kingdom. She became Prime Minister after winning the 1979 general election.
Thatcher introduced a series of economic policies intended to reverse high unemployment and Britain's struggles in the wake of the Winter of Discontent and an ongoing recession. Her political philosophy and economic policies emphasised deregulation (particularly of the financial sector), flexible labour markets, the privatisation of state-owned companies, and reducing the power and influence of trade unions. Thatcher's popularity in her first years in office waned amid recession and rising unemployment, until victory in the 1982 Falklands War and the recovering economy brought a resurgence of support, resulting in her decisive re-election in 1983. She survived an assassination attempt in the Brighton hotel bombing in 1984.
Thatcher was re-elected for a third term in 1987, but her subsequent support for the Community Charge ("poll tax") was widely unpopular, and her views on the European Community were not shared by others in her Cabinet. She resigned as Prime Minister and party leader in November 1990, after Michael Heseltine launched a challenge to her leadership. After retiring from the Commons in 1992, she was given a life peerage as Baroness Thatcher (of Kesteven in the County of Lincolnshire) which entitled her to sit in the House of Lords. In 2013, she died of a stroke in London at the age of 87.
Always a controversial figure, she is nonetheless viewed favourably in historical rankings of British prime ministers, and her tenure constituted a realignment towards neoliberal policies in the United Kingdom; despite the passage of time, debate over the complicated legacy of Thatcherism persists.Nestlé
Nestlé S.A. (, formerly ; French: [nɛsle]) is a Swiss multinational food and drink company headquartered in Vevey, Vaud, Switzerland. It is the largest food company in the world, measured by revenues and other metrics, since 2014. It ranked No. 64 on the Fortune Global 500 in 2017 and No. 33 on the 2016 edition of the Forbes Global 2000 list of largest public companies.Nestlé's products include baby food, medical food, bottled water, breakfast cereals, coffee and tea, confectionery, dairy products, ice cream, frozen food, pet foods, and snacks. Twenty-nine of Nestlé's brands have annual sales of over CHF1 billion (about US$1.1 billion), including Nespresso, Nescafé, Kit Kat, Smarties, Nesquik, Stouffer's, Vittel, and Maggi. Nestlé has 447 factories, operates in 189 countries, and employs around 339,000 people. It is one of the main shareholders of L'Oreal, the world's largest cosmetics company.Nestlé was formed in 1905 by the merger of the Anglo-Swiss Milk Company, established in 1866 by brothers George and Charles Page, and Farine Lactée Henri Nestlé, founded in 1866 by Henri Nestlé. The company grew significantly during the First World War and again following the Second World War, expanding its offerings beyond its early condensed milk and infant formula products. The company has made a number of corporate acquisitions, including Crosse & Blackwell in 1950, Findus in 1963, Libby's in 1971, Rowntree Mackintosh in 1988, Klim in 1998, and Gerber in 2007.
Nestlé has a primary listing on the SIX Swiss Exchange and is a constituent of the Swiss Market Index. It has a secondary listing on Euronext.Pasteurization
Pasteurization or pasteurisation is a process in which certain packaged and non-packaged foods (such as milk and fruit juice) are treated with mild heat, usually less than 100 °C (212 °F), to eliminate pathogens and extend shelf life. The process is intended to stabilize foods by destroying or inactivating organisms and enzymes that contribute to spoilage, including vegetative bacteria but not bacterial spores. Since pasteurization is not sterilization, and does not kill spores, a second "double" pasteurization will extend the quality by killing spores that have germinated.
The process was named after the French scientist Louis Pasteur, whose research in the 1880s demonstrated that thermal processing would inactivate unwanted microorganisms in wine. Spoilage enzymes are also inactivated during pasteurization. Today, pasteurization is used widely in the dairy industry and other food processing industries to achieve food preservation and food safety.Most liquid products are heat treated in a continuous system where heat can be applied using a plate heat exchanger and/or the direct or indirect use of hot water and steam. Due to the mild heat, there are minor changes to the nutritional quality and sensory characteristics of the treated foods. Pascalization or high pressure processing (HPP) and pulsed electric field (PEF) are non-thermal processes that are also used to pasteurize foods.Soy milk
Soy milk or soymilk is a plant-based drink produced by soaking and grinding soybeans, boiling the mixture, and filtering out remaining particulates. It is a stable emulsion of oil, water, and protein. Its original form is a natural by-product of the manufacture of tofu. It became a common beverage in Europe and North America in the later half of the 20th century, especially as production techniques were developed to give it taste and consistency more closely resembling dairy milk. Along with similar vegetable-based "milks", like almond and rice milk, soy milk may be used as a substitute for dairy milk by individuals who are vegan or lactose intolerant.Turmeric
Turmeric (pronounced , also or ) is a flowering plant, Curcuma longa of the ginger family, Zingiberaceae, the roots of which are used in cooking. The plant is a perennial, rhizomatous, herbaceous plant native to the Indian subcontinent and Southeast Asia, that requires temperatures between 20 and 30 °C (68 and 86 °F) and a considerable amount of annual rainfall to thrive. Plants are gathered each year for their rhizomes, some for propagation in the following season and some for consumption.
The rhizomes are used fresh or boiled in water and dried, after which they are ground into a deep orange-yellow powder commonly used as a coloring and flavoring agent in many Asian cuisines, especially for curries, as well as for dyeing. Turmeric powder has a warm, bitter, black pepper-like flavor and earthy, mustard-like aroma.Although long used in Ayurvedic medicine, where it is also known as haridra, no high-quality clinical evidence exists for use of turmeric or its constituent, curcumin, as a therapy.Yogurt
Yogurt ( or ; from Turkish: yoğurt), also spelled yoghurt, yogourt or yoghourt, is a food produced by bacterial fermentation of milk. The bacteria used to make yogurt are known as yogurt cultures. The fermentation of lactose by these bacteria produces lactic acid, which acts on milk protein to give yogurt its texture and characteristic tart flavor. Cow's milk is commonly available worldwide and, as such, is the milk most commonly used to make yogurt. Milk from water buffalo, goats, ewes, mares, camels, and yaks is also used to produce yogurt where available locally. The milk used may be homogenized or not, even pasteurized or raw. Each type of milk produces substantially different results.
Yogurt is produced using a culture of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus bacteria. In addition, other lactobacilli and bifidobacteria are sometimes added during or after culturing yogurt. Some countries require yogurt to contain a certain amount of colony-forming units (CFU) of bacteria; in China, for example, the requirement for the number of lactobacillus bacteria is at least 1 million CFU per milliliter.To produce yogurt, milk is first heated, usually to about 85 °C (185 °F), to denature the milk proteins so that they do not form curds. After heating, the milk is allowed to cool to about 45 °C (113 °F). The bacterial culture is mixed in, and that temperature of 45 °C is maintained for 4 to 12 hours to allow fermentation to occur.
|cooking Reduction %||10||30||20||25||25||35||0||0||30||10||15||20||10||20||5||10||25|
|%DV = % daily value i.e. % of DRI (Dietary Reference Intake)
Note: All nutrient values including protein and fiber are in %DV per 100 grams of the food item. Significant values are highlighted in light Gray color and bold letters.  Cooking reduction = % Maximum typical reduction in nutrients due to boiling without draining for ovo-lacto-vegetables group Q = Quality of Protein in terms of completeness without adjusting for digestability.