Food sources

Foods from plants
Food from plant sources
Food from plant sources

Many plants or plant parts are eaten as food. There are around two thousand plant species which are cultivated for food, and many have several distinct cultivars.[3] Plant-based foods can be classified as with the nutrients necessary for the plant's initial growth. Because of this, seeds are often packed with energy, and are good sources of food for animals, including humans. In fact, the majority of all foods consumed by human beings are seeds. These include cereals (such as maize, wheat, and rice), legumes (such as beans, peas, and lentils), and nuts. Oilseeds are often pressed to produce rich oils, including sunflower, rape (including canola oil), and sesame.[4]

Fruits are the ripened extensions of plants, including the seeds within. Fruits are made attractive to animals so that animals will eat the fruits and excrete the seeds over long distances. Fruits, therefore, make up a significant part of the diets of most cultures. Some fruits, such as pumpkin and eggplant, are eaten as vegetables.[5] (For more information, see list of fruits.)

Vegetables are other plant matter which is eaten as food. These include root vegetables (such as potatoes and carrots), leaf vegetables (such as spinach and lettuce), stem vegetables (such as bamboo shoots and asparagus), and inflorescence vegetables (such as globe artichokes and broccoli). Many herbs and spices are highly-flavorful vegetables.[6]

Foods from animals
Various raw meats
Various raw meats

Meat is eaten, either from muscle systems or from organs. Often other animal products are eaten as well. Mammals produce milk, which in many cultures is drunk or processed into dairy products such as cheese or butter.[7] Birds and other animals lay eggs, which are often eaten.[8] Many cultures eat honey, produced by bees, and some cultures eat animal blood.

Other foods

Some foods do not come from animal or plant sources. These include various edible fungi, including mushrooms. Fungi and ambient bacteria are used in the preparation of fermented and pickled foods such as leavened bread, wine, beer, cheese, pickles, and yogurt.[9] Many cultures eat seaweed, which is a protist, or blue-green algae (cyanobacteria) such as Spirulina.[10] Additionally, salt is often eaten as a flavoring or preservative, and baking soda is used in food preparation. Both of these are inorganic substances, as is water, an important part of human diet.

Legal definition

English-speaking countries usually define four categories of substances as food [11] [12] [13]:

* any substance, intended to be, or reasonably expected to be, ingested by humans;
* water and other drinks;
* chewing gum;
* substances used as ingredients in the preparation of food.

Food production

Main article: Agriculture

Food is traditionally obtained through farming, ranching, and fishing, with hunting, foraging and other methods of subsistence locally important. More recently, there has been a growing trend towards more Sustainable agricultural practices. This approach - which is partly fuelled by consumer demand - encourages biodiversity, local self-reliance and Organic farming methods.[14]

Major influences on food production are international policy, (e.g. the World Trade Organization and Common Agricultural Policy), national government policy (or law), and war.[15]

Food for livestock is fodder and traditionally comprises hay or grain.[16]

Food preparation
Food being prepared in large quantities
Food being prepared in large quantities

While some food can be eaten without preparation, many foods undergo some form of preparation for reasons of safety, palatability, or flavor. At the simplest level this may involve washing, cutting, trimming or adding other foods or ingredients, such as spices. It may also involve mixing, heating or cooling, pressure cooking, fermentation, or combination with other food.[17]

In a home, most food preparation takes place in a kitchen. Some preparation is done to enhance the taste or aesthetic appeal; other preparation may help to preserve the food; and others may be involved in cultural identity. A meal is made up of food which is prepared to be eaten at a specific time and place.[2][18]

The preparation of animal-based food will usually involve slaughter, evisceration, hanging, portioning and rendering. In developed countries, this is usually done outside the home.[19][20]

Cooking

Main article: Cooking

The term "cooking" encompasses a vast range of methods, tools and combinations of ingredients to improve the flavour or digestibility of food. It generally requires the selection, measurement and combining of ingredients in an ordered procedure in an effort to achieve the desired result. Constraints on success include the variability of ingredients, ambient conditions, tools, and the skill of the individual cooking.[17]

The diversity of cooking worldwide is a reflection of the myriad nutritional, aesthetic, agricultural, economic, cultural and religious considerations that impact upon it.[2]

Cooking requires applying heat to a food which usually, though not always, chemically transforms it, thus changing its flavor, texture, appearance, and nutritional properties.[21] Cooking proper, as opposed to roasting, requires the boiling of water in a container, and was practiced at least since the 10th millennium BC with the introduction of pottery.[22] There is archaeological evidence of roasted foodstuffs at Homo erectus campsites dating from 420,000 years ago.[23][24]

Food manufacture

Main article: Food manufacture

Packaged foods are manufactured outside the home for purchase. This can be as simple as a butcher preparing meat, or as complex as a modern international food industry.

Early food processing techniques were limited by available food preservation, packaging and transportation. This mainly involved salting, curing, curdling, drying, pickling and smoking.[25]

During the industrialisation era in the 19th century, food manufacturing arose.[26] This development took advantage of new mass markets and emerging new technology, such as milling, preservation, packaging and labelling and transportation. It brought the advantages of pre-prepared time saving food to the bulk of ordinary people who did not employ domestic servants.[27]

At the start of the 21st century, a two-tier structure has arisen, with a few international food processing giants controlling a wide range of well-known food brands. There also exists a wide array of small local or national food processing companies.[28] Advanced technologies have also come to change food manufacture. Computer-based control systems, sophisticated processing and packaging methods, and logistics and distribution advances, can enhance product quality, improve food safety, and reduce costs.[27]

Food trade
Some brand name foods
Some brand name foods
Gourmet foods
Gourmet foods

Food is now traded and marketed on a global basis.[29] The variety and availability of food is no longer restricted by the diversity of locally grown food or the limitations of the local growing season.[30] Between 1961 and 1999 there has been a 400% increase in worldwide food exports.[31] Some countries are now economically dependent on food exports, which in some cases account for over 80% of all exports.[32]

In 1994 over 100 countries became signatories to the Uruguay Round of the General Agreement on Tariffs and Trade in a dramatic increase in trade liberalisation. This included an agreement to reduce subsidies paid to farmers, underpinned by the WTO enforcement of agricultural subsidy, tariffs, import quotas and settlement of trade disputes that cannot be bilaterally resolved.[33] Where trade barriers are raised on the disputed grounds of public health and safety, the WTO refer the dispute to the Codex Alimentarius Commission, which was founded in 1962 by the United Nations Food and Agriculture Organization and the World Health Organization. This has greatly affected world food trade.[34]

Food marketing and retailing

Food marketing brings together the producer and the consumer. It is the chain of activities that brings food from “farm gate to plate.”[35] The marketing of even a single food product can be a complicated process involving many producers and companies. For example, fifty-six companies are involved in making one can of chicken noodle soup. These businesses include not only chicken and vegetable processors but also the companies that transport the ingredients and those who print labels and manufacture cans.[36] The food marketing system is the largest direct and indirect nongovernment employer in the United States.

In the pre-modern era, the sale of surplus food took place once a week when farmers took their wares on market day, into the local village market place. Here food was sold to grocers for sale in their local shops for purchase by local consumers.[2][27]

With the onset of industrialisation, and the development of the food processing industry, a wider range of food could be sold and distributed in distant locations. Typically early grocery shops would be counter-based shops, in which purchasers told the shop-keeper what they wanted, so that the shop-keeper could get it for them.[2][37]
Packaged food aisles of supermarket in Portland, Oregon
Packaged food aisles of supermarket in Portland, Oregon

In the 20th century supermarkets were born. Supermarkets brought with them a self service approach to shopping using shopping carts, and were able to offer quality food at lower cost through economies of scale and reduced staffing costs. In the latter part of the 20th century, this has been further revolutionised by the development of vast warehouse-sized out-of-town supermarkets, selling a wide range of food from around the world.[38]

Unlike food processors, food retailing is a two-tier market in which a small number of very large companies control a large proportion of supermarkets. The supermarket giants wield great purchasing power over farmers and processors, and strong influence over consumers.[28] Nevertheless, less than ten percent of consumer spending on food goes to farmers, with larger percentages going to advertising, transportation, and intermediate corporations.[39]

There are two basic views of food marketing: production focus and consumer focus. The production-focused view is an institutional one that is primarily concerned with producing a food as efficiently as possible and transporting it so it can eventually be sold. In this perspective, “marketing” is basically a distribution activity.

In contrast to this production perspective, the consumer-focused view involves understanding what exactly consumers want and providing it to them in a form, in a message, and at a profitable price. Whereas a production focus is typically not flexible enough to anticipate consumer demands and interests, a consumer focus necessitates this skill.[40]

The Food Marketing Mix and the Four Ps of Marketing

The four components of food marketing are often called the “four Ps” of the marketing mix because they relate to product, price, promotion, and place.[41] One reason food manufacturers receive the largest percentage of the retail food dollar is that they provide the most differentiating, value-added service. The money that manufacturers invest in developing, pricing, promotion, and placing their products helps differentiate a food product on the basis of both quality and brand-name recognition.

Product

In deciding what types of new food products a consumer would most prefer, a manufacturer can either try to develop a new food product or try to modify/extend an existing one. For example, a sweet, flavored yogurt drink would be a new product, a new flavor of milk (such as chocolate or strawberry) would be an extension of an existing product. There are three steps to both developing and extending: generate ideas, screen ideas for feasibility, and test ideas for appeal. Only after these steps will a food product make it to national market. Of one hundred new food product ideas considered, only six make it to a supermarket shelf.

Price

In profitably pricing the food, the manufacturer must keep in mind that the retailer takes approximately 50 percent of the price of a product. A frozen food sold in a retail store for $4.50 generates an income of $2.25 for the manufacturer. This money has to pay for the cost of producing, packaging, shipping, storing, and selling the product.

Promotion

Promoting a food to consumers is done out of store, in store, and on package. Advertisements on television and in magazines are attempts to persuade consumers to think favorably about a product, so that they go to the store to purchase the product. In addition to advertising, promotions can also include Sunday newspaper ads that offer coupons such as cents-off and buy-one-get-one-free offers.

Place

Place refers to the distribution and warehousing efforts necessary to move a food from the manufacturer to a location where a consumer can buy it. It can also relate to the place within a store that it is located.

Famine and hunger

Food deprivation leads to malnutrition and ultimately starvation. This is often connected with famine, which involves the absence of food in entire communities. This can have a devastating and widespread effect on human health and mortality. Rationing is sometimes used to distribute food in times of shortage, most notably during times of war.[15]

Starvation is a significant international problem. Approximately 815 million people are undernourished, and over 16,000 children die per day from hunger-related causes.[42] Besides starvation, insufficient food causes nearly a third of all babies born worldwide to die prematurely or have disabilities.[43] Food deprivation is regarded as a deficit need in Maslow's hierarchy of needs and is measured using famine scales.[44]

Food aid

Food aid can benefit people suffering from a shortage of food. It can be used to improve peoples' lives in the short term, so that a society can increase its standard of living to the point that food aid is no longer required.[45] Conversely, badly managed food aid can create problems by disrupting local markets, depressing crop prices, and discouraging food production. Sometimes a cycle of food aid dependence can develop.[46] Its provision, or threatened withdrawal, is sometimes used as a political tool to influence the politics of the destination country. Sometimes, also, food aid provisions will require certain types of food be purchased from certain sellers, and food aid can be misused to enhance the markets of donor countries.[47][48] International efforts to distribute food to the neediest countries are often co-ordinated by the World Food Programme.[49]

Food safety

Main article: Food safety

Foodborne illness, commonly called "food poisoning," is caused by bacteria, toxins, viruses, parasites, and prions. Roughly 7 million people die of food poisoning each year, with about 10 times as many suffering from a non-fatal version.[50]

The two most common factors leading to cases of bacterial foodborne illness are cross-contamination of ready-to-eat food from other uncooked foods and improper temperature control. Less commonly, acute adverse reactions can also occur if chemical contamination of food occurs, for example from improper storage, or use of non-food grade soaps and disinfectants. Food can also be adulterated by a very wide range of articles (known as 'foreign bodies') during farming, manufacture, cooking, packaging, distribution or sale. These foreign bodies can include pests or their droppings, hairs, cigarette butts, wood chips, and all manner of other contaminants. It is possible for certain types of food to become contaminated if stored or presented in an unsafe container, such as a ceramic pot with lead-based glaze.[50]

Food poisoning has been recognised as a disease of man since as early as Hippocrates.[51] The sale of rancid, contaminated or adulterated food was commonplace until introduction of hygiene, refrigeration, and vermin controls in the 19th century. Discovery of techniques for killing bacteria using heat and other microbiological studies by scientists such as Louis Pasteur contributed to the modern sanitation standards that we enjoy today. This was further underpinned by the work of Justus von Liebig whose work led to the development of modern food storage and food preservation methods.[52] In more recent years, a greater understanding of the causes of food-borne illnesses has led to the development of more systematic approaches such as HACCP, which can identify and eliminate many risks.[53]

Food allergies

Main article: food allergy

Some people have allergies or sensitivities to foods which are not problematic to most people. This occurs when a person's immune system mistakes a certain food protein for a harmful foreign agent and attacks it. About 2% of adults and 8% of children have a food allergy.[54] The amount of the food substance required to provoke a reaction in a susceptible individual can be minute. For instance, tiny amounts of food in the air, too minute to be smelled, have been known to provoke lethal reactions in sufficiently sensitive individuals. Commonly food allergens are gluten, corn, shellfish (mollusks), peanuts, and soy. Most patients present with diarrhea after ingesting certain foodstuffs, skin symptoms (rashes), bloating, vomiting and regurgitation. The digestive complaints usually develop within half an hour of ingesting the allergen.[54]

Rarely, the food allergy chelce can lead to anaphylactic shock: hypotension (low blood pressure) and loss of consciousness. This is a medical emergency. An allergen associated with this type of reaction is peanut, although latex products can induce similar reactions.[54] Initial treatment is with epinephrine (adrenaline), often carried by known patients in the form of an Epi-pen.[55]

Dietary habits

Main article: Diet (nutrition)

Dietary habits are the habitual decisions a person or culture makes when choosing what foods to eat.[56] Although humans are omnivores, each culture holds some food preferences and some food taboos.[57] Dietary choices can also define cultures and play a role in religion. For example, only Kosher foods are permitted by Judaism, and Halal/Haram foods by Islam, in the diet of believers.[58] In addition, the dietary choices of different countries or regions have different characteristics. This is highly related to a culture's cuisine.

Dietary habits play a significant role in the health and mortality of all humans. Imbalances between the consumed fuels and expended energy results in either starvation or excessive reserves of adipose tissue, known as body fat.[59] Poor intake of various vitamins and minerals can lead to diseases which can have far-reaching effects on health. For instance, 30% of the world's population either has, or is at risk for developing, Iodine deficiency.[60] It is estimated that at least 3 million children are blind due to vitamin A deficiency.[61] Vitamin C deficiency results in scurvy.[62] Calcium, Vitamin D and phosphorus are inter-related; the consumption of each may affect the absorption of the others. Kwashiorkor and marasmus are childhood disorders caused by lack of dietary protein.[63] Obesity, a serious problem in the western world, leads to higher chances of developing heart disease, diabetes, and many other diseases.[64]

Many individuals limit what foods they eat for reasons of health, morality, or other habit.[65] For instance vegetarians choose to forgo food from animal sources to varying degrees. Others choose a healthier diet, avoiding sugars or animal fats and increasing consumption of dietary fiber and antioxidants.[66]

More recently, dietary habits have been influenced by the concerns that some people have about possible impacts on health or the environment from genetically modified food.[67] Further concerns about the impact of industrial farming on animal welfare, human health and the environment are also having an effect on contemporary human dietary habits. This has led to the emergence of a counterculture with a preference for organic and local food.[68]

Nutrients in food

Main article: Nutrition

Between the extremes of optimal health and death from starvation or malnutrition, there is an array of disease states that can be caused or alleviated by changes in diet. Deficiencies, excesses and imbalances in diet can produce negative impacts on health, which may lead to diseases such as scurvy, obesity or osteoporosis, as well as psychological and behavioral problems. The science of nutrition attempts to understand how and why specific dietary aspects influence health.

Nutrients in food are grouped into several categories. Macronutrients means fat, protein, and carbohydrates. Micronutrients are the minerals and vitamins. Additionally food contains water and dietary fiber.