Margarine
Margarine (Template:PronEng or Template:IPA). As a generic term, it can indicate any of a wide range of butter substitutes. In many parts of the world, margarine has become the best-selling table spread, although butter and olive oil also command large market shares. Margarine is an ingredient in the preparation of many other foods. In some regions people may refer to margarine as butter in informal speech, but in several countries laws forbid food packaging to refer to margarine as "butter". Recipes sometimes refer to margarine as oleo or as shortening.

# History
Margarine has a long and sometimes confusing history. Its name originates with the discovery by Michel Eugene Chevreul in 1813 of "margaric acid" (itself named after the pearly deposits of the fatty acid from Greek , - or  (margaris, -ites / margaron), meaning "a pearl-oyster" or "a pearl"). Scientists at the time regarded margaric acid, like oleic acid and stearic acid, as one of the three fatty acids which, in combination, formed most animal fats. In 1853 the German structural chemist Wilhelm Heinrich Heintz analyzed margaric acid as simply a combination of stearic acid and of the previously unknown palmitic acid.
In 1869 Emperor Louis Napoleon III of France offered a prize to anyone who could make a satisfactory substitute for butter, suitable for use by the armed forces and the lower classes. French chemist Hippolyte Mege-Mouries invented a substance he called oleomargarine, the name of which became shortened to the trade name "Margarine". Margarine now refers generically to any of a range of broadly similar edible oils. The name oleomargarine is sometimes abbreviated to oleo.
Manufacturers produced oleomargarine by taking clarified vegetable fat, extracting the liquid portion under pressure, and then allowing it to solidify. When combined with butyrin and water, it made a cheap and more-or-less palatable butter-substitute. Sold as Margarine or under any of a host of other trade names, butter-substitutes soon became a substantial market segment  but too late to help Mege-Mouries: although he expanded his initial manufacturing operation from France to the United States in 1873, he had little commercial success. By the end of the decade both the old world and the new could buy artificial butters.
From that time on, two main trends would dominate the margarine industry: on one hand a series of refinements and improvements to the product and its manufacture, and on the other a long and bitter struggle with the dairy industry, which defended itself from the margarine industry with vigor. As early as 1877 the first U.S. states had passed laws to restrict the sale and labelling of margarine. By the mid-1880s the United States federal government had introduced a tax of two cents per pound, and devotees needed an expensive license to make or sell the product. Individual states began to require the clear labelling of margarine, banning passing it off as real butter.
The key to slowing margarine sales (and protecting the established dairy industries), however, emerged as restricting its color. Margarine naturally appears white or almost white: by forbidding the addition of artificial coloring-agents, legislators found that they could keep margarine off kitchen tables. Bans on coloration became commonplace around the world and endured for almost 100 years. It did not become legal to sell colored margarine in Australia, for example, until the 1960s.

## Margarine in the USA
In the United States, the color bans, drafted by the butter lobby, began in the dairy states of New York and New Jersey.  In several states, the legislature enacted laws to force margarine manufacturers to add pink colorings to make the product look unpalatable, but the Supreme Court struck down New Hampshire's law and overruled these measures.  By the start of the 20th century, eight out of ten Americans could not buy yellow margarine, and those that could had to pay a hefty tax on it.  Bootleg colored margarine became common, and manufacturers began to supply food-coloring capsules so that the consumer could knead the yellow color into margarine before serving it.  Nevertheless, the regulations and taxes had a significant effect: the 1902 restrictions on margarine color, for example, cut annual U.S. consumption from 120 million to 48 million pounds (54,000 to 22,000 tons). However, by the end of the 1910s, it had become more popular than ever.
With the coming of World War I, margarine consumption increased enormously, even in unscathed regions like the United States. In the countries closest to the fighting, dairy products became almost unobtainable and were strictly rationed. The United Kingdom, for example, depended on imported butter from Australia and New Zealand and the risk of submarine attack meant that little arrived.  Margarine became the staple spread, and butter a rare and expensive luxury.
The long-running rent-seeking battle between the margarine and dairy lobbies continued: in the United States, the Great Depression brought a renewed wave of pro-dairy legislation; the Second World War, a swing back to margarine. Post-war, the margarine lobby gained power and, little by little, the main margarine restrictions were lifted, the last state to do so being Wisconsin in 1967.  However, some vestiges of the legal restrictions remain in the U.S.: the Food, Drug, and Cosmetic Act still prohibits the retail sale of margarine in packages larger than one pound .

## Margarine in Canada
In Canada, margarine was banned from 1886 until 1948 though this ban was temporarily lifted from 1917 until 1923 due to dairy shortages. Nevertheless, bootleg margarine was produced in neighboring British colony of Newfoundland from whale, seal and fish oil by the Newfoundland Butter Company (which, in fact, produced only margarine) and was smuggled to Canada where it was widely sold for half the price of butter. The Supreme Court of Canada lifted the margarine ban in 1948. In 1950, as a result of a court ruling giving provinces the right to regulate the product, rules were implemented in much of Canada regarding margarine's color requiring it to be bright yellow or orange in some provinces or colorless in others. By the 1980s most provinces had lifted the restriction, however, in Ontario it was not legal to sell butter-colored margarine until 1995. As of 2008, Quebec, which requires margarine to be colorless, is the only jurisdiction in North America to regulate the color of margarine. Quebec's margarine law was upheld by the Supreme Court of Canada in 2005.

# Margarine today
In the meantime, margarine manufacturers had made many changes. Modern margarine can be made from any of a wide variety of animal or vegetable fats, and is often mixed with skimmed milk, salt, and emulsifiers. Margarine made from vegetable oils is especially important in today's market, as it provides a substitute for butter which is both vegan and pareve. Nearly all margarine is salted, which makes shortening (which contains no salt) a better choice for baking.
In terms of microstructure, margarine is a water-in-oil emulsion, containing dispersed water droplets of typically 5-10 m diameter. The amount of crystallizing fat in the continuous oil+fat phase determines the firmness of the product. In the relevant temperature range, saturated fats contribute most to the amount of crystalline fat, whereas monounsaturated and polyunsaturated fats contribute relatively little to the amount of crystalline fat in the product. Mono- and poly-unsaturated fats and oils can be transformed into suitable substrates by the chemical process of hydrogenation, which renders them solid at room temperature. Full hydrogenation results in saturated fats only, but partial hydrogenation will lead to the formation of trans-fats as well (see Trans fat).
Three main types of margarine are common:
- Hard, generally uncolored margarine for cooking or baking. (Shortening)
- "Traditional" margarines for such uses as spreading on toast, which contain saturated fats, are mostly made from vegetable oils.
- Margarines high in mono- or poly-unsaturated fats, which are made from safflower, sunflower, soybean, cottonseed, rapeseed, or olive oil, and which are said to be healthier than butter or other types of margarine.
Many popular table spreads today are blends of margarine and butter  something that was long illegal in countries including the United States and Australia  and are designed to combine the lower cost and easy-spreading of artificial butter with the taste of the real thing.
Margarine, particularly polyunsaturated margarine, has become a major part of the Western diet. In the United States, for example, in 1930 the average person ate over 18 lb (8 kg) of butter a year and just over 2 lb (900g) of margarine. By the end of the 20th century, an average American ate just under 4 lb (1.8 kg) of butter and nearly 8 lb (3.6 kg) of margarine.
Under European Union directives, margarine products cannot be called "butter", even if most of it consists of natural butter. In some European countries butter based table spreads and margarine products are marketed as "butter mixtures".
These "butter mixtures" compose a significant portion of the table spread market. The brand "I Can't Believe It's Not Butter" spawned a variety of similarly-named spreads that can be found on supermarket shelves all over the world. With names like "Utterly Butterly," "You'd Butter Believe it," "Unbelieveable! This Is Not Butter," and "Butterlicious," these butter mixtures avoid the restrictions on labeling with marketing techniques that imply a strong similarity to real butter.
The United States imports 10 billion pounds (4.5 million tons) of margarine a year. Additionally, the United States exports 2 billion pounds (900,000 tons) of margarine annually.
Margarine has a particular market to Orthodox Jews. The laws of Kashrut (the Jewish dietary laws) forbid the mixing of meat and dairy products, and hence there are strictly Kosher margarines available, which are often used by Jews adapting recipes that use meat and butter to be Kosher.

# Nutrition
Discussions concerning the nutritional value of margarine revolve around two aspects: the total amount of fat, and the types of fat (saturated fat, trans fat). Usually, a comparison between margarine and butter is included in this context as well.

## Amount of fat
Fat consumption in the Western world is quite high. Traditional margarine (~80% fat) contributes to this, but is not the main factor causing over-consumption. Low-fat spreads could serve as an alternative, and are widely available.
The roles of butter and margarine are quite similar with respect to their energy content.

## Saturated fat
The saturated fatty acids in triglycerides contribute to elevated blood cholesterol levels, which in turn has often been linked to cardiovascular diseases.
Vegetable fats can contain anything between 10% and 100% saturated fatty acids. Liquid oils tend to be on the low end (unhardened canola oil, soy bean oil); fully hardened oils are at the high end of the scale. A margarine blend is a mixture of both types of components, and will rarely exceed 50% saturated fatty acids on fat. Exceptions are some traditional kitchen margarines or products that have to maintain stability under tropical conditions. Generally, firmer margarines contain more saturated fat.
Regular butterfat contains ~65% saturated fatty acids on fat , although this varies somewhat with season. One tablespoon of butter contains over 7g of saturated fat.

## Trans fat
Several large studies  indicate a strong link between shortened life and consumption of high amounts of trans fat. The United States Food and Drug Administration (FDA), the National Heart, Lung and Blood Institute and the American Heart Association (AHA) all have recommended people to limit intake of trans-fat.
Trans fats do not occur naturally in vegetable fats but are a consequence of partial hydrogenation of the fats (in contrast, full hydrogenation does not generate trans fats, but only fully saturated fats). Particularly in the US, partial hydrogenation has been common as a result of the dependence on a very limited number of vegetable oil sources. In other parts of the world, the industry started to move away from using partially hydrogenated oils since the mid-nineties , and produce new margarine varieties that contain less or no trans fat . Many manufacturers in the US now label their products according to government regulations now as "zero grams" trans-fat, which effectively means less than 500 mg trans-fat per serving.
Butterfat contains 2-5% trans fatty acids (mainly C18:1w7).

## Cholesterol
The intake of cholesterol has less of an effect on high blood cholesterol levels than saturated fat.. The FDA states that healthy people should not consume more than 200 mg of cholesterol each day, and butter contains approximately 33 mg of cholesterol in each tablespoon.. Margarine contains no cholesterol.

## Plant sterol/stanol esters
Plant sterol esters or plant stanol esters have been added to some margarines and spreads because of their cholesterol lowering effect.
Several studies have indicated that consumption of about 2 grams per day provides a reduction in LDL cholesterol of about 10%.
Sterol/stanol esters are tasteless and odorless, and have the same physical and chemical properties typical of most fats. However, they do not enter the the blood stream but instead pass through the gut. Thus they suit well to be used in low-fat spreads.