Butter is a dairy product made by churning fresh or fermented cream or milk. It is generally used as a spread and a condiment, as well as in cooking, such as baking, sauce making, and panfrying. Butter consists of butterfat, milk proteins and water.
Most frequently made from cows' milk, butter can also be manufactured from the milk of other mammals, including sheep, goats, buffalo, and yaks. Salt, flavorings and preservatives are sometimes added to butter. Rendering butter produces clarified butter or ghee, which is almost entirely butterfat.
Butter is a water-in-oil emulsion resulting from an inversion of the cream, an oil-in-water emulsion; the milk proteins are the emulsifiers. Butter remains a solid when refrigerated, but softens to a spreadable consistency at room temperature, and melts to a thin liquid consistency at 32–35 °C (90–95 °F). The density of butter is 911 g/L (56.9 lb/ft3).[1] It generally has a pale yellow color, but varies from deep yellow to nearly white.
Contents
[show]Etymology[edit]
The word butter derives (via Germanic languages) from the Latin butyrum,[2] which is the latinisation of the Greek βούτυρον (bouturon).[3][4] This may have been a construction meaning "cow-cheese", from βοῦς (bous), "ox, cow"[5] + τυρός (turos), "cheese",[6] but perhaps this is a false etymology of a Scythian word.[7] Nevertheless, the earliest attested form of the second stem, turos ("cheese"), is the Mycenaean Greek tu-ro, written in Linear B syllabic script.[8] The root word persists in the name butyric acid, a compound found in rancid butter and dairy products such as Parmesan cheese.
In general use, the term "butter" refers to the spread dairy product when unqualified by other descriptors. The word commonly is used to describe puréed vegetable or seed & nut products such as peanut butter and almond butter. It is often applied to spread fruit products such as apple butter. Fats such as cocoa butter and shea butter that remain solid at room temperature are also known as "butters". In addition to the act of applying butter being called "to butter", non-dairy items that have a dairy butter consistency may use "butter' to call that consistency to mind, including food items such as maple butter and witch's butter and nonfood items such as baby bottom butter, hyena butter, and rock butter.
Production[edit]
Main article: Churning (butter)
Unhomogenized milk and cream contain butterfat in microscopic globules. These globules are surrounded by membranes made of phospholipids (fatty acid emulsifiers) and proteins, which prevent the fat in milk from pooling together into a single mass. Butter is produced by agitating cream, which damages these membranes and allows the milk fats to conjoin, separating from the other parts of the cream. Variations in the production method will create butters with different consistencies, mostly due to the butterfat composition in the finished product. Butter contains fat in three separate forms: free butterfat, butterfat crystals, and undamaged fat globules. In the finished product, different proportions of these forms result in different consistencies within the butter; butters with many crystals are harder than butters dominated by free fats.
Almost all commercially-made butter today begins with pasteurized cream, which is commonly heated to a relatively high temperature above 80 °C (180 °F). Before it is churned, the cream is cooled to about 5 °C (40 °F) and allowed to remain at that temperature for at least eight hours; under these conditions about half the butterfat in the cream crystallizes. The jagged crystals of fat inflict damage upon the fat globule membranes during churning, speeding the butter-making process.
Churning produces small butter grains floating in the water-based portion of the cream. This watery liquid is called buttermilk—although the buttermilk most common today is instead a directly fermented skimmed milk. The buttermilk is drained off; sometimes more buttermilk is removed by rinsing the grains with water. Then the grains are "worked": pressed and kneaded together. When prepared manually, this is done using wooden boards called scotch hands. This consolidates the butter into a solid mass and breaks up embedded pockets of buttermilk or water into tiny droplets.
Commercial butter is about 80% butterfat and 15% water; traditionally made butter may have as little as 65% fat and 30% water. Butterfat is a mixture of triglyceride, a triester derived from glycerol and three of any of several fatty acid groups.[9] Butter becomes rancid when these chains break down into smaller components, like butyric acid and diacetyl. The density of butter is 0.911 g/cm3 (0.527 oz/in3), about the same as ice.
Types[edit]
Before modern factory butter making, cream was usually collected from several milkings and was therefore several days old and somewhat fermented by the time it was made into butter. Butter made from a fermented cream is known ascultured butter. During fermentation, the cream naturally sours as bacteria convert milk sugars into lactic acid. The fermentation process produces additional aroma compounds, including diacetyl, which makes for a fuller-flavored and more "buttery" tasting product.[10] Today, cultured butter is usually made from pasteurized cream whose fermentation is produced by the introduction of Lactococcus and Leuconostoc bacteria.
Another method for producing cultured butter, developed in the early 1970s, is to produce butter from fresh cream and then incorporate bacterial cultures and lactic acid. Using this method, the cultured butter flavor grows as the butter is aged in cold storage. For manufacturers, this method is more efficient, since aging the cream used to make butter takes significantly more space than simply storing the finished butter product. A method to make an artificial simulation of cultured butter is to add lactic acid and flavor compounds directly to the fresh-cream butter; while this more efficient process is claimed to simulate the taste of cultured butter, the product produced is not cultured but is instead flavored.
Dairy products are often pasteurized during production to kill pathogenic bacteria and other microbes. Butter made from pasteurized fresh cream is called sweet cream butter. Production of sweet cream butter first became common in the 19th century, with the development of refrigeration and the mechanical cream separator.[11] Butter made from fresh or cultured unpasteurized cream is called raw cream butter. While butter made from pasteurized cream may keep for several months, raw cream butter has a shelf life of roughly ten days.
Throughout continental Europe, cultured butter is preferred, while sweet cream butter dominates in the United States and the United Kingdom. Therefore, cultured butter is sometimes labeled "European-style" butter in the United States. Commercial raw cream butter is virtually unheard-of in the United States. Raw cream butter is generally only found made at home by consumers who have purchased raw whole milk directly from dairy farmers, skimmed the cream themselves, and made butter with it. It is rare in Europe as well.[12]
Several "spreadable" butters have been developed; these remain softer at colder temperatures and are therefore easier to use directly out of refrigeration. Some modify the makeup of the butter's fat through chemical manipulation of the finished product, some through manipulation of the cattle's feed, and some by incorporating vegetable oils into the butter. "Whipped" butter, another product designed to be more spreadable, is aerated via the incorporation of nitrogen gas—normal air is not used, because doing so would encourage oxidation and rancidity.
All categories of butter are sold in both salted and unsalted forms. Either granular salt or a strong brine are added to salted butter during processing. In addition to enhanced flavor, the addition of salt acts as a preservative.
The amount of butterfat in the finished product is a vital aspect of production. In the United States, products sold as "butter" are required to contain a minimum of 80% butterfat; in practice, most American butters contain only slightly more than that, averaging around 81% butterfat. European butters generally have a higher ratio, which may extend up to 85%.
Clarified butter is butter with almost all of its water and milk solids removed, leaving almost-pure butterfat. Clarified butter is made by heating butter to its melting point and then allowing it to cool; after settling, the remaining components separate by density. At the top, whey proteins form a skin which is removed, and the resulting butterfat is then poured off from the mixture of water and casein proteins that settle to the bottom.[13]
Ghee is clarified butter which is brought to higher temperatures of around 120 °C (250 °F) once the water had evaporated, allowing the milk solids to brown. This process flavors the ghee, and also producesantioxidants which help protect it longer from rancidity. Because of this, ghee can keep for six to eight months under normal conditions.[13]
Cream may be skimmed from whey instead of milk, as a byproduct of cheese-making. Whey butter may be made from whey cream. Whey cream and butter have a lower fat content and taste more salty, tangy and "cheesy".[14] They are also cheaper than "sweet" cream and butter.
European butters[edit]
There are several butters produced in Europe with Protected geographical indications; these include:
- Beurre d'Ardenne, from Belgium
- Beurre d'Isigny, from France
- Beurre Charentes-Poitou (Which also includes: Beurre des Charentes and Beurre des Deux-Sèvres under the same classification), from France
- Beurre Rose, from Luxembourg
- Mantequilla de Soria, from Spain
- Mantega de l'Alt Urgell i la Cerdanya, from Spain
History[edit]
The earliest butter would have been from sheep or goat's milk; cattle are not thought to have been domesticated for another thousand years.[15]
There is evidence of milkfat in stone age containers dating back to 6,500 BC. Perhaps because liquid milk doesn't leave evidence easily preserved, or because it spoils easily, this earliest evidence points to butter, cheese, and yogurt, as if they were used by humans before liquid milk.[16]
Cow's milk butter first shows up in ancient Mesopotamia in 2,500 BC, where a sumerian tablet illustrates its creation.
An ancient method of butter making, still used today in parts of Africa and the Near East, involves a goat skin half filled with milk, and inflated with air before being sealed. The skin is then hung with ropes on a tripod of sticks, and rocked until the movement leads to the formation of butter.
In the Mediterranean climate, unclarified butter spoils quickly— unlike cheese, it is not a practical method of preserving the nutrients of milk. The ancient Greeks and Romans seemed to have considered butter a food fit more for the northern barbarians. A play by the Greek comic poet Anaxandrides refers to Thracians as boutyrophagoi, "butter-eaters".[17] In Natural History, Pliny the Eldercalls butter "the most delicate of food among barbarous nations", and goes on to describe its medicinal properties.[18] Later, the physician Galen also described butter as a medicinal agent only.[19]
Historian and linguist Andrew Dalby says most references to butter in ancient Near Eastern texts should more correctly be translated as ghee. Ghee is mentioned in the Periplus of the Erythraean Seaas a typical trade article around the first century CE Arabian Sea, and Roman geographer Strabo describes it as a commodity of Arabia and Sudan.[17] In India, ghee has been a symbol of purity and an offering to the gods—especially Agni, the Hindu god of fire—for more than 3000 years; references to ghee's sacred nature appear numerous times in the Rigveda, circa 1500–1200 BCE. The tale of the child Krishna stealing butter remains a popular children's story in India today. Since India's prehistory, ghee has been both a staple food and used for ceremonial purposes, such as fueling holy lamps and funeral pyres.
Middle Ages[edit]
The cooler climates of northern Europe allowed butter to be stored for a longer period before it spoiled. Scandinavia has the oldest tradition in Europe of butter export trade, dating at least to the 12th century.[20] After the fall of Rome and through much of the Middle Ages, butter was a common food across most of Europe, but one with a low reputation, and was consumed principally by peasants. Butter slowly became more accepted by the upper class, notably when the early 16th century Roman Catholic Church allowed its consumption during Lent. Bread and butter became common fare among the middle class, and the English, in particular, gained a reputation for their liberal use of melted butter as a sauce with meat and vegetables.[21]
In antiquity, butter was used for fuel in lamps as a substitute for oil. The Butter Tower of Rouen Cathedral was erected in the early 16th century when Archbishop Georges d'Amboise authorized the burning of butter instead of oil, which was scarce at the time, during Lent.[22]
Across northern Europe, butter was sometimes treated in a manner unheard-of today: it was packed into barrels (firkins) and buried in peat bogs, perhaps for years. Such "bog butter" would develop a strong flavor as it aged, but remain edible, in large part because of the unique cool, airless, antiseptic and acidic environment of a peat bog. Firkins of such buried butter are a common archaeological find in Ireland; the Irish National Museum has some containing "a grayish cheese-like substance, partially hardened, not much like butter, and quite free from putrefaction." The practice was most common in Ireland in the 11th–14th centuries; it ended entirely before the 19th century.[20]
Industrialization[edit]
Like Ireland, France became well known for its butter, particularly in Normandy and Brittany. By the 1860s, butter had become so in demand in France that Emperor Napoleon III offered prize money for an inexpensive substitute to supplement France's inadequate butter supplies. A French chemist claimed the prize with the invention of margarine in 1869. The first margarine was beef tallow flavored with milk and worked like butter; vegetable margarine followed after the development of hydrogenated oils around 1900.
Until the 19th century, the vast majority of butter was made by hand, on farms. The first butter factories appeared in the United States in the early 1860s, after the successful introduction of cheesefactories a decade earlier. In the late 1870s, the centrifugal cream separator was introduced, marketed most successfully by Swedish engineer Carl Gustaf Patrik de Laval.[23] This dramatically sped up the butter-making process by eliminating the slow step of letting cream naturally rise to the top of milk. Initially, whole milk was shipped to the butter factories, and the cream separation took place there. Soon, though, cream-separation technology became small and inexpensive enough to introduce an additional efficiency: the separation was accomplished on the farm, and the cream alone shipped to the factory. By 1900, more than half the butter produced in the United States was factory made; Europe followed suit shortly after.
In 1920, Otto Hunziker authored The Butter Industry, Prepared for Factory, School and Laboratory,[24] a well-known text in the industry that enjoyed at least three editions (1920, 1927, 1940). As part of the efforts of the American Dairy Science Association, Professor Hunziker and others published articles regarding: causes of tallowiness[25] (an odor defect, distinct from rancidity, a taste defect); mottles[26] (an aesthetic issue related to uneven color); introduced salts;[27] the impact of creamery metals[28] and liquids;[29] and acidity measurement.[30] These and other ADSA publications helped standardize practices internationally.
Butter also served as a source of extra income for farm families. Wood presses featuring intricate decoration were used to press the butter into pucks or small bricks to be sold at a nearby market or general store with the decoration identifying the farm which produced the butter. This continued until production was mechanized and butter was produced in less decorative stick form.[31] Today butter presses continue to be used for decorative purposes.
Per capita butter consumption declined in most western nations during the 20th century, in large part because of the rising popularity of margarine, which is less expensive and, until recent years, was perceived as being healthier. In the United States, margarine consumption overtook butter during the 1950s,[32] and it is still the case today that more margarine than butter is eaten in the U.S. and the EU.[33]
Size and shape of butter packaging[edit]
In the United States, butter is usually produced in 4-ounce sticks, wrapped in waxed or foiled paper and sold four to a one-pound carton. This practice is believed to have originated in 1907, when Swift and Company began packaging butter in this manner for mass distribution.[34]
These sticks are commonly produced in two different shapes:
- The dominant shape east of the Rocky Mountains is the Elgin, or Eastern-pack shape, named for a dairy in Elgin, Illinois. The sticks are 121 millimetres (4.8 in) long and 32 millimetres (1.3 in) wide and are typically sold stacked two by two in elongated cube-shaped boxes.[35]
- West of the Rocky Mountains, butter printers standardized on a different shape that is now referred to as the Western-pack shape. These butter sticks are 80 millimetres (3.1 in) long and 38 millimetres (1.5 in) wide and are usually sold with four sticks packed side-by-side in a flat, rectangular box.[35] The shape was altered for the West Coast because of the higher average temperature; having a smaller surface-area-to-volume ratio allowed the stick of butter to remain on the counter longer without melting.[36]
Both sticks contain the same amount of butter, although most butter dishes are designed for Elgin-style butter sticks.[35]
The stick's wrapper is usually marked off as eight tablespoons (120 ml or 4.2 imp fl oz; 4.1 US fl oz); the actual volume of one stick is approximately nine tablespoons (130 ml or 4.6 imp fl oz; 4.4 US fl oz).
Outside of the United States, butter is packaged and sold by weight only, not by volume (fluid measure) nor by unit (stick), but the package shape remains approximately the same. The wrapper is usually a foil and waxed-paper laminate (the waxed paper is now a siliconised substitute, but is still referred to in some places as parchment, from the wrapping used in past centuries; and the term 'parchment-wrapped' is still employed where the paper alone is used, without the foil laminate).
In the UK and Ireland, and in some other regions historically accustomed to using British measures, this was traditionally ½lb and 1 lb packs; since metrication, these countries have shifted to the same system the rest of the metricated world uses.
In the remainder of the metricated world, butter is packed and sold in 250g and 500g packs (roughly equivalent to the ½lb and 1 lb measures) and measured for cooking in grams or kilograms; although melted butter could be measured by fluid measure (centiliters or fluid ounces), this is rare.
Butter for commercial and industrial use is packaged in plastic buckets, tubs, or drums, in quantities and units suited to the local market.
No comments:
Post a Comment