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81-644: Potteries may refer to: Pottery , or pottery manufacturing Places in England [ edit ] Staffordshire Potteries , the Stoke-on-Trent area, known as the after its once-important ceramics industry The Potteries Urban Area , a conurbation distinct from, and covering a larger area than, the Staffordshire Potteries Potteries Shopping Centre ,

162-428: A communal fire , and can be enjoyed by all members of the family, although in many cultures women bear primary responsibility. Cooking is also often carried out outside of personal quarters, for example at restaurants, or schools. Bakeries were one of the earliest forms of cooking outside the home, and bakeries in the past often offered the cooking of pots of food provided by their customers as an additional service. In

243-588: A deep cave) of controlled use of fire to cook food by archaic humans was dated to ~780,000 years ago . Anthropologists think that widespread cooking fires began about 250,000 years ago when hearths first appeared. Recently, the earliest hearths have been reported to be at least 790,000 years old. Communication between the Old World and the New World in the Columbian Exchange influenced

324-503: A desirable texture. Fats are one of the three main macronutrient groups in human diet , along with carbohydrates and proteins , and the main components of common food products like milk , butter , tallow , lard , salt pork , and cooking oils . They are a major and dense source of food energy for many animals and play important structural and metabolic functions, in most living beings, including energy storage, waterproofing, and thermal insulation . The human body can produce

405-400: A differentiated culture which was earlier thought to be typical Indus Valley civilisation (IVC) culture. Pottery is durable, and fragments, at least, often survive long after artifacts made from less-durable materials have decayed past recognition. Combined with other evidence, the study of pottery artefacts is helpful in the development of theories on the organisation, economic condition and

486-510: A large cranial capacity meant that early Homo habilis regularly cooked food. However, unequivocal evidence in the archaeological record for the controlled use of fire begins at 400,000 BCE, long after Homo erectus . Archaeological evidence from 300,000 years ago, in the form of ancient hearths, earth ovens , burnt animal bones, and flint , are found across Europe and the Middle East. The oldest evidence (via heated fish teeth from

567-459: A locality. The main ingredient of the body is clay . Some different types used for pottery include: It is common for clays and other raw materials to be mixed to produce clay bodies suited to specific purposes. Various mineral processing techniques are often utilised before mixing the raw materials, with comminution being effectively universal for non-clay materials. Examples of non-clay materials include: The production of pottery includes

648-416: A more distant connection between groups, such as trade in the same market or even relatively close settlements. Techniques that require more studied replication (i.e., the selection of clay and the fashioning of clay) may indicate a closer connection between peoples, as these methods are usually only transmissible between potters and those otherwise directly involved in production. Such a relationship requires

729-424: A number of diseases, including diabetes, chronic kidney disease, cancer and cardiovascular diseases, as well as in ageing. AGEs are a group of compounds that are formed between reducing sugars and amino acids via Maillard reaction . These compounds impart colors, tastes and smells that are specific to these food, but may also be deleterious to health. Dry heat (e.g. in roasting or grilling) can significantly increase

810-519: A number of ways in cooking and baking. To prepare stir fries , grilled cheese or pancakes , the pan or griddle is often coated with fat or oil. Fats are also used as an ingredient in baked goods such as cookies , cakes and pies. Fats can reach temperatures higher than the boiling point of water, and are often used to conduct high heat to other ingredients, such as in frying, deep frying or sautéing. Fats are used to add flavor to food (e.g., butter or bacon fat), prevent food from sticking to pans and create

891-724: A per calorie basis while providing more fiber , calcium , and iron . The ingredients are also directly sourced, so there is control over authenticity, taste, and nutritional value. The superior nutritional quality of home-cooking could therefore play a role in preventing chronic disease . Cohort studies following the elderly over 10 years show that adults who cook their own meals have significantly lower mortality, even when controlling for confounding variables. "Home-cooking" may be associated with comfort food , and some commercially produced foods and restaurant meals are presented through advertising or packaging as having been "home-cooked", regardless of their actual origin. This trend began in

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972-581: A rough guide, modern earthenwares are normally fired at temperatures in the range of about 1,000  °C (1,830 °F) to 1,200 °C (2,190 °F); stonewares at between about 1,100 °C (2,010 °F) to 1,300 °C (2,370 °F); and porcelains at between about 1,200 °C (2,190 °F) to 1,400 °C (2,550 °F). Historically, reaching high temperatures was a long-lasting challenge, and earthenware can be fired effectively as low as 600 °C (1,112 °F), achievable in primitive pit firing . The time spent at any particular temperature

1053-475: A shopping centre in Hanley, Stoke-on-Trent Other uses [ edit ] Potteries, Shrewsbury and North Wales Railway , England and Wales Potteries dialect , of Midlands English Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Potteries . If an internal link led you here, you may wish to change the link to point directly to

1134-399: A subdiscipline of food science concerning the physical and chemical transformations that occur during cooking. Important contributions have been made by scientists, chefs and authors such as Hervé This (chemist), Nicholas Kurti (physicist), Peter Barham (physicist), Harold McGee (author), Shirley Corriher (biochemist, author), Robert Wolke (chemist, author.) It is different for

1215-483: A toasted crust is formed generates significant concentrations of acrylamide . This discovery in 2002 led to international health concerns. Subsequent research has however found that it is not likely that the acrylamides in burnt or well-cooked food cause cancer in humans; Cancer Research UK categorizes the idea that burnt food causes cancer as a "myth". Cooking food at high temperature may create advanced glycation end-products (AGEs) that are believed to be involved in

1296-512: A waterproof barrier, and improve its durability. Below are the major types of glazing commonly used in pottery: 1. Glossy Glaze - Produces a shiny, reflective surface. - Highlights intricate patterns and textures. - Often used for decorative purposes. 2. Matte Glaze - Provides a smooth, non-reflective finish. - Suitable for modern and minimalist designs. - Ideal for functional wares like plates and mugs, as it minimizes glare. 3. Transparent Glaze - Can be glossy or matte. - Allows

1377-470: A wide variety of foods, and processed cereals quickly became a defining feature of the American breakfast. In the 1920s, freezing methods , cafeterias , and fast food restaurants emerged. Most ingredients in cooking are derived from living organisms . Vegetables, fruits, grains and nuts as well as herbs and spices come from plants, while meat, eggs, and dairy products come from animals. Mushrooms and

1458-401: Is also important, the combination of heat and time is known as heatwork . Kilns can be monitored by pyrometers , thermocouples and pyrometric devices . The atmosphere within a kiln during firing can affect the appearance of the body and glaze. Key to this is the differing colours of the various oxides of iron, such as iron(III) oxide (also known as ferric oxide or Fe 2 O 3 ) which

1539-706: Is an aspect of all human societies and a cultural universal . Types of cooking also depend on the skill levels and training of the cooks . Cooking is done both by people in their own dwellings and by professional cooks and chefs in restaurants and other food establishments. Preparing food with heat or fire is an activity unique to humans . Archeological evidence of cooking fires from at least 300,000 years ago exists, but some estimate that humans started cooking up to 2 million years ago. The expansion of agriculture , commerce , trade , and transportation between civilizations in different regions offered cooks many new ingredients. New inventions and technologies, such as

1620-485: Is associated with brown-red colours, whilst iron(II) oxide (also known as ferrous oxide or FeO) is associated with much darker colours, including black. The oxygen concentration in the kiln influences the type, and relative proportions, of these iron oxides in fired the body and glaze: for example, where there is a lack of oxygen during firing the associated carbon monoxide (CO) will readily react with oxygen in Fe 2 O 3 in

1701-641: Is especially prone to oxidation during cooking and may be completely destroyed by protracted cooking. The bioavailability of some vitamins such as thiamin , vitamin B6 , niacin , folate , and carotenoids are increased with cooking by being freed from the food microstructure. Blanching or steaming vegetables is a way of minimizing vitamin and mineral loss in cooking. There are many methods of cooking, most of which have been known since antiquity. These include baking, roasting, frying, grilling, barbecuing, smoking, boiling, steaming and braising. A more recent innovation

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1782-400: Is important part of archaeology for understanding the archaeological culture of the excavated site by studying the fabric of artifacts, such as their usage, source material composition, decorative pattern, color of patterns, etc. This helps to understand characteristics, sophistication , habits, technology, tools, trade, etc. of the people who made and used the pottery. Carbon dating reveals

1863-426: Is lit and the woman runs around the circumference of the mound touching the burning torch to the dried grass. Some mounds are still being constructed as others are already burning. Pottery may be decorated in many different ways. Some decoration can be done before or after the firing, and may be undertaken before or after glazing. Glaze is a glassy coating on pottery, and reasons to use it include decoration, ensuring

1944-425: Is made by heating materials, generally including kaolin , in a kiln to temperatures between 1,200 and 1,400 °C (2,200 and 2,600 °F). This is higher than used for the other types, and achieving these temperatures was a long struggle, as well as realizing what materials were needed. The toughness, strength and translucence of porcelain, relative to other types of pottery, arises mainly from vitrification and

2025-722: Is microwaving. Various methods use differing levels of heat and moisture and vary in cooking time. The method chosen greatly affects the result. Some major hot cooking techniques include: As of 2021, over 2.6 billion people cook using open fires or inefficient stoves using kerosene , biomass , and coal as fuel. These cooking practices use fuels and technologies that produce high levels of household air pollution, causing 3.8 million premature deaths annually. Of these deaths, 27% are from pneumonia , 27% from ischaemic heart disease , 20% from chronic obstructive pulmonary disease , 18% from stroke , and 8% from lung cancer . Women and young children are disproportionately affected, since they spend

2106-469: Is no high-quality evidence for its efficacy against human diseases. The United States Department of Agriculture has studied retention data for 16 vitamins, 8 minerals, and alcohol for approximately 290 foods across various cooking methods. In a human epidemiological analysis by Richard Doll and Richard Peto in 1981, diet was estimated to cause a large percentage of cancers. Studies suggest that around 32% of cancer deaths may be avoidable by changes to

2187-638: Is normally fired below 1200 °C. Because unglazed earthenware is porous, it has limited utility for the storage of liquids or as tableware. However, earthenware has had a continuous history from the Neolithic period to today. It can be made from a wide variety of clays, some of which fire to a buff, brown or black colour, with iron in the constituent minerals resulting in a reddish-brown. Reddish coloured varieties are called terracotta , especially when unglazed or used for sculpture. The development of ceramic glaze made impermeable pottery possible, improving

2268-481: Is not always the case; for example fritware uses no or little clay, so falls outside these groups. Historic pottery of all these types is often grouped as either "fine" wares, relatively expensive and well-made, and following the aesthetic taste of the culture concerned, or alternatively "coarse", "popular", "folk" or "village" wares, mostly undecorated, or simply so, and often less well-made. Cooking in pottery became less popular once metal pots became available, but

2349-430: Is placed within the context of linguistic and migratory patterns, it becomes an even more prevalent category of social artifact. As proposed by Olivier P. Gosselain, it is possible to understand ranges of cross-cultural interaction by looking closely at the chaîne opératoire of ceramic production. The methods used to produce pottery in early Sub-Saharan Africa are divisible into three categories: techniques visible to

2430-405: Is shaped by a variety of techniques, which include: Prior to firing, the water in an article needs to be removed. A number of different stages, or conditions of the article, can be identified: Firing produces permanent and irreversible chemical and physical changes in the body. It is only after firing that the article or material is pottery. In lower-fired pottery, the changes include sintering ,

2511-455: Is still used for dishes that benefit from the qualities of pottery cooking, typically slow cooking in an oven, such as biryani , cassoulet , daube , tagine , jollof rice , kedjenou , cazuela and types of baked beans . The earliest forms of pottery were made from clays that were fired at low temperatures, initially in pit-fires or in open bonfires . They were hand formed and undecorated. Earthenware can be fired as low as 600 °C, and

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2592-421: Is uncooked or done rare , and unboiled water. The sterilizing effect of cooking depends on temperature, cooking time, and technique used. Some food spoilage bacteria such as Clostridium botulinum or Bacillus cereus can form spores that survive cooking or boiling, which then germinate and regrow after the food has cooled. This makes it unsafe to reheat cooked food more than once. Cooking increases

2673-400: The "clay matrix" – composed of grains of less than 0.02 mm grains which can be seen using the high-powered microscopes or a scanning electron microscope , and the "clay inclusions" – which are larger grains of clay and could be seen with the naked eye or a low-power binocular microscope. For geologists, fabric analysis means spatial arrangement of minerals in a rock. For Archaeologists,

2754-566: The "fabric analysis" of pottery entails the study of clay matrix and inclusions in the clay body as well as the firing temperature and conditions . Analysis is done to examine the following 3 in detail: The Six fabrics of Kalibangan is a good example of fabric analysis. Body , or clay body, is the material used to form pottery. Thus a potter might prepare, or order from a supplier, such an amount of earthenware body, stoneware body or porcelain body. The compositions of clay bodies varies considerably, and include both prepared and 'as dug';

2835-640: The National Cancer Institute found that human subjects who ate beef rare or medium-rare had less than one third the risk of stomach cancer than those who ate beef medium-well or well-done. While avoiding meat or eating meat raw may be the only ways to avoid HCA's in meat fully, the National Cancer Institute states that cooking meat below 212 °F (100 °C) creates "negligible amounts" of HCA's. Also, microwaving meat before cooking may reduce HCAs by 90% by reducing

2916-629: The Neolithic period , with ceramic objects such as the Gravettian culture Venus of Dolní Věstonice figurine discovered in the Czech Republic dating back to 29,000–25,000 BC. However, the earliest known pottery vessels were discovered in Jiangxi , China, which date back to 18,000 BC. Other early Neolithic and pre-Neolithic pottery artifacts have been found, in Jōmon Japan (10,500 BC),

2997-540: The Russian Far East (14,000 BC), Sub-Saharan Africa (9,400 BC), South America (9,000s–7,000s BC), and the Middle East (7,000s–6,000s BC). Pottery is made by forming a clay body into objects of a desired shape and heating them to high temperatures (600–1600 °C) in a bonfire , pit or kiln , which induces reactions that lead to permanent changes including increasing the strength and rigidity of

3078-406: The specific heat of an object, thermal conductivity , and (perhaps most significantly) the difference in temperature between the two objects. Thermal diffusivity is the combination of specific heat, conductivity and density that determines how long it will take for the food to reach a certain temperature. Home cooking has traditionally been a process carried out informally in a home or around

3159-543: The " Danger zone " temperature range from 40 to 140 °F (4 to 60 °C), food therefore should not be stored in this temperature range. Washing of hands and surfaces, especially when handling different meats, and keeping raw food separate from cooked food to avoid cross-contamination, are good practices in food preparation. Foods prepared on plastic cutting boards may be less likely to harbor bacteria than wooden ones. Washing and disinfecting cutting boards, especially after use with raw meat, poultry, or seafood, reduces

3240-710: The Atlantic from the Old World, such as cattle , sheep , pigs , wheat , oats , barley , rice , apples , pears , peas , chickpeas , mustard , and carrots , similarly changed New World cooking. In the 17th and 18th centuries, food was a classic marker of identity in Europe. In the 19th-century "Age of Nationalism ", cuisine became a defining symbol of national identity. The Industrial Revolution brought mass-production, mass-marketing, and standardization of food. Factories processed, preserved, canned, and packaged

3321-503: The ability of the involved parties to communicate effectively, implying pre-existing norms of contact or a shared language between the two. Thus, the patterns of technical diffusion in pot-making that are visible via archaeological findings also reveal patterns in societal interaction. Chronologies based on pottery are often essential for dating non-literate cultures and are often of help in the dating of historic cultures as well. Trace-element analysis , mostly by neutron activation , allows

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3402-452: The age. Sites with similar pottery characteristics have the same culture, those sites which have distinct cultural characteristics but with some overlap are indicative of cultural exchange such as trade or living in vicinity or continuity of habitation, etc. Examples are black and red ware , redware , Sothi-Siswal culture and Painted Grey Ware culture . The six fabrics of Kalibangan is a good example of use of fabric analysis in identifying

3483-558: The application of scientific knowledge to cooking, that is "molecular cooking" (for the technique) or "molecular cuisine" (for a culinary style), for which chefs such as Raymond Blanc, Philippe and Christian Conticini, Ferran Adria , Heston Blumenthal , Pierre Gagnaire (chef). Chemical processes central to cooking include hydrolysis (in particular beta elimination of pectins, during the thermal treatment of plant tissues), pyrolysis, and glycation reactions wrongly named Maillard reactions . Cooking foods with heat depends on many factors:

3564-417: The branches and then grass is piled high to complete the mound. Although the mound contains the pots of many women, who are related through their husbands' extended families, each women is responsible for her own or her immediate family's pots within the mound. When a mound is completed and the ground around has been swept clean of residual combustible material, a senior potter lights the fire. A handful of grass

3645-480: The case of potatoes where most vitamin C is in the skin. However, research has shown that in the specific case of carotenoids a greater proportion is absorbed from cooked vegetables than from raw vegetables. Sulforaphane , a glucosinolate breakdown product, is present in vegetables such as broccoli , and is mostly destroyed when the vegetable is boiled. Although there has been some basic research on how sulforaphane might exert beneficial effects in vivo, there

3726-401: The common sugar, sucrose (table sugar), a disaccharide , and such simple sugars as glucose (made by enzymatic splitting of sucrose) and fructose (from fruit), and starches from sources such as cereal flour, rice, arrowroot and potato. The interaction of heat and carbohydrate is complex. Long-chain sugars such as starch tend to break down into more digestible simpler sugars . If

3807-431: The cultural development of the societies that produced or acquired pottery. The study of pottery may also allow inferences to be drawn about a culture's daily life, religion, social relationships, attitudes towards neighbours, attitudes to their own world and even the way the culture understood the universe. It is valuable to look into pottery as an archaeological record of potential interaction between peoples. When pottery

3888-412: The diet. Some of these cancers may be caused by carcinogens in food generated during the cooking process, although it is often difficult to identify the specific components in diet that serve to increase cancer risk. Several studies published since 1990 indicate that cooking meat at high temperature creates heterocyclic amines (HCA's), which are thought to increase cancer risk in humans. Researchers at

3969-437: The digestibility of many foods which are inedible or poisonous when raw. For example, raw cereal grains are hard to digest, while kidney beans are toxic when raw or improperly cooked due to the presence of phytohaemagglutinin , which is inactivated by cooking for at least ten minutes at 100 °C (212 °F). Food safety depends on the safe preparation, handling, and storage of food. Food spoilage bacteria proliferate in

4050-635: The dish being cooked. In European cooking, a mixture of butter and flour called a roux is used to thicken liquids to make stews or sauces. In Asian cooking, a similar effect is obtained from a mixture of rice or corn starch and water. These techniques rely on the properties of starches to create simpler mucilaginous saccharides during cooking, which causes the familiar thickening of sauces . This thickening will break down, however, under additional heat. Types of fat include vegetable oils , animal products such as butter and lard , as well as fats from grains, including maize and flax oils. Fats are used in

4131-480: The duration of firing influences the final characteristics of the ceramic. Thus, the maximum temperature within a kiln is often held constant for a period of time to soak the wares to produce the maturity required in the body of the wares. Kilns may be heated by burning combustible materials, such as wood , coal and gas , or by electricity . The use of microwave energy has been investigated. When used as fuels, coal and wood can introduce smoke, soot and ash into

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4212-460: The eye (decoration, firing and post-firing techniques), techniques related to the materials (selection or processing of clay, etc.), and techniques of molding or fashioning the clay. These three categories can be used to consider the implications of the reoccurrence of a particular sort of pottery in different areas. Generally, the techniques that are easily visible (the first category of those mentioned above) are thus readily imitated, and may indicate

4293-711: The fat it requires from other food ingredients, except for a few essential fatty acids that must be included in the diet. Dietary fats are also the carriers of some flavor and aroma ingredients and vitamins that are not water-soluble . Edible animal material, including muscle , offal , milk, eggs and egg whites , contains substantial amounts of protein. Almost all vegetable matter (in particular legumes and seeds ) also includes proteins, although generally in smaller amounts. Mushrooms have high protein content. Any of these may be sources of essential amino acids . When proteins are heated they become denatured (unfolded) and change texture. In many cases, this causes

4374-430: The following stages: Before being shaped, clay must be prepared. This may include kneading to ensure an even moisture content throughout the body. Air trapped within the clay body needs to be removed, or de-aired, and can be accomplished either by a machine called a vacuum pug or manually by wedging . Wedging can also help produce an even moisture content. Once a clay body has been kneaded and de-aired or wedged, it

4455-486: The foot) is left unglazed or, alternatively, special refractory " spurs " are used as supports. These are removed and discarded after the firing. Some specialised glazing techniques include: Types of Glazing in Pottery. Glazing in pottery is the process of applying a coating or layer of material to ceramics that, when fired, forms a vitreous or glass-like surface. Glazes enhance the aesthetic appeal of pottery, provide

4536-659: The formation of the mineral mullite within the body at these high temperatures. Although porcelain was first made in China , the Chinese traditionally do not recognise it as a distinct category, grouping it with stoneware as "high-fired" ware, opposed to "low-fired" earthenware. This confuses the issue of when it was first made. A degree of translucency and whiteness was achieved by the Tang dynasty (AD 618–906), and considerable quantities were being exported. The modern level of whiteness

4617-443: The former being by far the dominant type for studio and industry. The properties also vary considerably, and include plasticity and mechanical strength before firing; the firing temperature needed to mature them; properties after firing, such as permeability, mechanical strength and colour. There can be regional variations in the properties of raw materials used for pottery, and these can lead to wares that are unique in character to

4698-412: The fusing together of coarser particles in the body at their points of contact with each other. In the case of porcelain, where higher firing-temperatures are used, the physical, chemical and mineralogical properties of the constituents in the body are greatly altered. In all cases, the reason for firing is to permanently harden the wares, and the firing regime must be appropriate to the materials used. As

4779-425: The glaze. Cooking Cooking , also known as cookery or professionally as the culinary arts , is the art, science and craft of using heat to make food more palatable , digestible , nutritious , or safe . Cooking techniques and ingredients vary widely, from grilling food over an open fire , to using electric stoves , to baking in various types of ovens , reflecting local conditions. Cooking

4860-460: The history of cooking. The movement of foods across the Atlantic from the New World, such as potatoes , tomatoes , maize , beans , bell pepper , chili pepper , vanilla , pumpkin , cassava , avocado , peanut , pecan , cashew , pineapple , blueberry , sunflower , chocolate , gourds , green beans , and squash , had a profound effect on Old World cooking. The movement of foods across

4941-435: The intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Potteries&oldid=1093245473 " Categories : Disambiguation pages Place name disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Pottery Pottery is one of the oldest human inventions , originating before

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5022-780: The invention of pottery for holding and boiling of water , expanded cooking techniques. Some modern cooks apply advanced scientific techniques to food preparation to further enhance the flavor of the dish served. Phylogenetic analysis suggests that early hominids may have adopted cooking 1 million to 2 million years ago. Re-analysis of burnt bone fragments and plant ashes from the Wonderwerk Cave in South Africa has provided evidence supporting control of fire by early humans by 1 million years ago. In his seminal work Catching Fire: How Cooking Made Us Human , Richard Wrangham suggested that evolution of bipedalism and

5103-417: The item is impermeable to liquids, and minimizing the adherence of pollutants. Glaze may be applied by spraying, dipping, trailing or brushing on an aqueous suspension of the unfired glaze. The colour of a glaze after it has been fired may be significantly different from before firing. To prevent glazed wares sticking to kiln furniture during firing, either a small part of the object being fired (for example,

5184-431: The kiln which can affect the appearance of unprotected wares. For this reason, wares fired in wood- or coal-fired kilns are often placed in the kiln in saggars , ceramic boxes, to protect them. Modern kilns fuelled by gas or electricity are cleaner and more easily controlled than older wood- or coal-fired kilns and often allow shorter firing times to be used. Niche techniques include: [...] pots are positioned on and amid

5265-586: The late Middle Ages, as European kilns were less efficient, and the right type of clay less common. It remained a speciality of Germany until the Renaissance. Stoneware is very tough and practical, and much of it has always been utilitarian, for the kitchen or storage rather than the table. But "fine" stoneware has been important in China , Japan and the West, and continues to be made. Many utilitarian types have also come to be appreciated as art. Porcelain

5346-845: The most time near the hearth. Hazards while cooking can include To prevent those injuries there are protections such as cooking clothing, anti-slip shoes, fire extinguisher and more. Cooking can prevent many foodborne illnesses that would otherwise occur if raw food is consumed. When heat is used in the preparation of food, it can kill or inactivate harmful organisms, such as bacteria and viruses, as well as various parasites such as tapeworms and Toxoplasma gondii . Food poisoning and other illness from uncooked or poorly prepared food may be caused by bacteria such as pathogenic strains of Escherichia coli , Salmonella typhimurium and Campylobacter , viruses such as noroviruses , and protozoa such as Entamoeba histolytica . Bacteria, viruses and parasites may be introduced through salad, meat that

5427-424: The object. Much pottery is purely utilitarian, but some can also be regarded as ceramic art . An article can be decorated before or after firing. Pottery is traditionally divided into three types: earthenware , stoneware and porcelain . All three may be glazed and unglazed. All may also be decorated by various techniques. In many examples the group a piece belongs to is immediately visually apparent, but this

5508-453: The popularity and practicality of pottery vessels. Decoration has evolved and developed through history. Stoneware is pottery that has been fired in a kiln at a relatively high temperature, from about 1,100 °C to 1,200 °C, and is stronger and non-porous to liquids. The Chinese, who developed stoneware very early on, classify this together with porcelain as high-fired wares. In contrast, stoneware could only be produced in Europe from

5589-492: The present day, factory food preparation has become common, with many "ready-to-eat" as well as "ready-to-cook" foods being prepared and cooked in factories and home cooks using a mixture of scratch made , and factory made foods together to make a meal . The nutritional value of including more commercially prepared foods has been found to be inferior to home-made foods. Home-cooked meals tend to be healthier with fewer calories, and less saturated fat , cholesterol and sodium on

5670-399: The production of AGEs, as well as food rich in animal protein and fats. The production of AGEs during cooking can be significantly reduced by cooking in water or moist heat, reducing the cooking times and temperatures, as well as by first marinating the meat in acidic ingredients such as lemon juice and vinegar. The scientific study of cooking has become known as molecular gastronomy. This is

5751-421: The raw materials and cause it to be reduced to FeO. An oxygen deficient condition, called a reducing atmosphere, is generated by preventing the complete combustion of the kiln fuel; this is achieved by deliberately restricting the supply of air or by supplying an excess of fuel. Firing pottery can be done using a variety of methods, with a kiln being the usual firing method. Both the maximum temperature and

5832-775: The remaining flavor and ingredients; this is a critical component of both stewing and sauce making. Vitamins and minerals are required for normal metabolism ; and what the body cannot manufacture itself must come from external sources. Vitamins come from several sources including fresh fruit and vegetables ( Vitamin C ), carrots, liver ( Vitamin A ), cereal bran, bread, liver (B vitamins), fish liver oil ( Vitamin D ) and fresh green vegetables ( Vitamin K ). Many minerals are also essential in small quantities including iron, calcium , magnesium , sodium chloride and sulfur ; and in very small quantities copper, zinc and selenium . The micronutrients, minerals, and vitamins in fruit and vegetables may be destroyed or eluted by cooking. Vitamin C

5913-405: The risk of contamination. Proponents of raw foodism argue that cooking food increases the risk of some of the detrimental effects on food or health. They point out that during cooking of vegetables and fruit containing vitamin C , the vitamin elutes into the cooking water and becomes degraded through oxidation. Peeling vegetables can also substantially reduce the vitamin C content, especially in

5994-471: The sources of clay to be accurately identified and the thermoluminescence test can be used to provide an estimate of the date of last firing. Examining sherds from prehistory, scientists learned that during high-temperature firing, iron materials in clay record the state of the Earth's magnetic field at that moment. The "clay body" is also called the "paste" or the "fabric" , which consists of 2 things,

6075-505: The structure of the material to become softer or more friable – meat becomes cooked and is more friable and less flexible. In some cases, proteins can form more rigid structures, such as the coagulation of albumen in egg whites. The formation of a relatively rigid but flexible matrix from egg white provides an important component in baking cakes, and also underpins many desserts based on meringue . Cooking often involves water, and water-based liquids. These can be added in order to immerse

6156-538: The substances being cooked (this is typically done with water, stock or wine). Alternatively, the foods themselves can release water. A favorite method of adding flavor to dishes is to save the liquid for use in other recipes . Liquids are so important to cooking that the name of the cooking method used is often based on how the liquid is combined with the food, as in steaming , simmering , boiling , braising and blanching . Heating liquid in an open container results in rapidly increased evaporation , which concentrates

6237-490: The sugars are heated so that all water of crystallisation is driven off, caramelization starts, with the sugar undergoing thermal decomposition with the formation of carbon , and other breakdown products producing caramel . Similarly, the heating of sugars and proteins causes the Maillard reaction , a basic flavor-enhancing technique. An emulsion of starch with fat or water can, when gently heated, provide thickening to

6318-442: The time needed for the meat to be cooked at high heat. Nitrosamines are found in some food, and may be produced by some cooking processes from proteins or from nitrites used as food preservatives; cured meat such as bacon has been found to be carcinogenic, with links to colon cancer. Ascorbate , which is added to cured meat, however, reduces nitrosamine formation. Baking, grilling or broiling food, especially starchy foods, until

6399-579: The underlying decoration or texture of the pottery to show through. - Often used over underglaze decorations. 4. Opaque Glaze - Completely covers the surface of the pottery, hiding any underlying texture or decoration. - Useful for creating uniform, bold colors. 5. Celadon Glaze - A translucent glaze, usually in shades of green or blue. - Originated in China and is popular in East Asian ceramics. - Accentuates carved or textured designs beneath

6480-405: The yeast used in baking are kinds of fungi . Cooks also use water and minerals such as salt . Cooks can also use wine or spirits . Naturally occurring ingredients contain various amounts of molecules called proteins , carbohydrates and fats . They also contain water and minerals. Cooking involves a manipulation of the chemical properties of these molecules. Carbohydrates include

6561-520: Was not reached until much later, in the 14th century. Porcelain was also made in Korea and in Japan from the end of the 16th century, after suitable kaolin was located in those countries. It was not made effectively outside East Asia until the 18th century. The study of pottery can help to provide an insight into past cultures. Fabric analysis (see section below), used to analyse the fabric of pottery ,

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