Freezing food preserves it from the time it is prepared to the time it is eaten. Since early times, farmers, fishermen, and trappers have preserved grains and produce in unheated buildings during the winter season. Freezing food slows down decomposition by turning residual moisture into ice, inhibiting the growth of most bacterial species. In the food commodity industry, there are two processes: mechanical and cryogenic (or flash freezing). The freezing kinetics is important to preserve the food quality and texture. Quicker freezing generates smaller ice crystals and maintains cellular structure. Cryogenic freezing is the quickest freezing technology available due to the ultra low liquid nitrogen temperature −196 °C (−320 °F).
Ultimate Indo-European origin of the word is the subject of continued debate. Some scholars have noted the similarities between the words for wine in Indo-European languages (e.g. Armenian gini, Latin vinum, Ancient Greek οἶνος, Russian вино [vʲɪˈno]), Kartvelian (e.g. Georgian ღვინო [ɣvinɔ]), and Semitic (*wayn; Hebrew יין [jaiin]), pointing to the possibility of a common origin of the word denoting "wine" in these language families. The Georgian word goes back to Proto-Kartvelian *ɣwino-, which is either a borrowing from Proto-Indo-European or the lexeme was specifically borrowed from Proto-Armenian *ɣʷeinyo-, whence Armenian gini. An alternate hypothesis by Fähnrich supposes *ɣwino- a native Kartvelian word derived from the verbal root *ɣun- ('to bend'). See *ɣwino- for more. All these theories place the origin of the word in the same geographical location, Trans-Caucasia, that has been established based on archeological and biomolecular studies as the origin of viticulture.
Cooking can prevent many foodborne illnesses that would otherwise occur if the food is eaten raw. 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 is uncooked or done rare, and unboiled water.
Communication between the Old World and the New World in the Columbian Exchange influenced 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, and squash, had a profound effect on Old World cooking. The movement of foods across the Atlantic, from the Old World, such as cattle, sheep, pigs, wheat, oats, barley, rice, apples, pears, peas, chickpeas, green beans, mustard, and carrots, similarly changed New World cooking.
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.
Some experts have said that speculation has merely aggravated other factors, such as climate change, competition with bio-fuels and overall rising demand. However, some such as Jayati Ghosh, professor of economics at Jawaharlal Nehru University in New Delhi, have pointed out that prices have increased irrespective of supply and demand issues: Ghosh points to world wheat prices, which doubled in the period from June to December 2010, despite there being no fall in global supply.
Finger food is food meant to be eaten directly using the hands, in contrast to food eaten with a knife and fork, spoon, chopsticks, or other utensils. In some cultures, food is almost always eaten with the hands; for example, Ethiopian cuisine is eaten by rolling various dishes up in injera bread. Foods considered street foods are frequently, though not exclusively, finger foods.
Prison food is the term for meals served to prisoners while incarcerated in correctional institutions. While some prisons prepare their own food, many use staff from on-site catering companies. Many prisons today support the requirements of specific religions, as well as vegetarianism. It is said that prison food of many developed countries is adequate to maintain health and dieting.[unreliable source?]
Most food has its origin in plants. Some food is obtained directly from plants; but even animals that are used as food sources are raised by feeding them food derived from plants. Cereal grain is a staple food that provides more food energy worldwide than any other type of crop. Corn (maize), wheat, and rice – in all of their varieties – account for 87% of all grain production worldwide. Most of the grain that is produced worldwide is fed to livestock.