Certain exceptions to the ban on alcohol apply. Alcohol derived from a source other than the grape (or its byproducts) and the date is allowed in "very small quantities" (loosely defined as a quantity that does not cause intoxication) under the Sunni Hanafi madhab, for specific purposes (such as medicines), where the goal is not intoxication. However, modern Hanafi scholars regard alcohol consumption as totally forbidden.
Literary references to wine are abundant in Homer (8th century BC, but possibly relating earlier compositions), Alkman (7th century BC), and others. In ancient Egypt, six of 36 wine amphoras were found in the tomb of King Tutankhamun bearing the name "Kha'y", a royal chief vintner. Five of these amphoras were designated as originating from the king's personal estate, with the sixth from the estate of the royal house of Aten. Traces of wine have also been found in central Asian Xinjiang in modern-day China, dating from the second and first millennia BC.
Some countries list a legal definition of food, often referring them with the word foodstuff. These countries list food as any item that is to be processed, partially processed, or unprocessed for consumption. The listing of items included as food include any substance intended to be, or reasonably expected to be, ingested by humans. In addition to these foodstuffs, drink, chewing gum, water, or other items processed into said food items are part of the legal definition of food. Items not included in the legal definition of food include animal feed, live animals (unless being prepared for sale in a market), plants prior to harvesting, medicinal products, cosmetics, tobacco and tobacco products, narcotic or psychotropic substances, and residues and contaminants.
Foods that spoil easily, such as meats, dairy, and seafood, must be prepared a certain way to avoid contaminating the people for whom they are prepared. As such, the rule of thumb is that cold foods (such as dairy products) should be kept cold and hot foods (such as soup) should be kept hot until storage. Cold meats, such as chicken, that are to be cooked should not be placed at room temperature for thawing, at the risk of dangerous bacterial growth, such as Salmonella or E. coli.
Wine can also be made from other species of grape or from hybrids, created by the genetic crossing of two species. V. labrusca (of which the Concord grape is a cultivar), V. aestivalis, V. rupestris, V. rotundifolia and V. riparia are native North American grapes usually grown to eat fresh or for grape juice, jam, or jelly, and only occasionally made into wine.
Sourness is caused by the taste of acids, such as vinegar in alcoholic beverages. Sour foods include citrus, specifically lemons, limes, and to a lesser degree oranges. Sour is evolutionarily significant as it is a sign for a food that may have gone rancid due to bacteria. Many foods, however, are slightly acidic, and help stimulate the taste buds and enhance flavor.
Natural foods and "all natural foods" are widely used terms in food labeling and marketing with a variety of definitions, most of which are vague. The term is often assumed to imply foods that are not processed and whose ingredients are all natural products (in the chemist's sense of that term), thus conveying an appeal to nature. But the lack of standards in most jurisdictions means that the term assures nothing. In some countries, the term "natural" is defined and enforced. In others, such as the United States, it is not enforced.
A 2003 report by archaeologists indicates a possibility that grapes were mixed with rice to produce mixed fermented drinks in China in the early years of the seventh millennium BC. Pottery jars from the Neolithic site of Jiahu, Henan, contained traces of tartaric acid and other organic compounds commonly found in wine. However, other fruits indigenous to the region, such as hawthorn, cannot be ruled out. If these drinks, which seem to be the precursors of rice wine, included grapes rather than other fruits, they would have been any of the several dozen indigenous wild species in China, rather than Vitis vinifera, which was introduced there 6000 years later.
Human diet was estimated to cause perhaps around 35% of cancers in a human epidemiological analysis by Richard Doll and Richard Peto in 1981. These cancer may be caused by carcinogens that are present in food naturally or as contaminants. Food contaminated with fungal growth may contain mycotoxins such as aflatoxins which may be found in contaminated corn and peanuts. Other carcinogens identified in food include heterocyclic amines generated in meat when cooked at high temperature, polyaromatic hydrocarbons in charred meat and smoked fish, and nitrosamines generated from nitrites used as food preservatives in cured meat such as bacon.