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. 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.
Some traditional foods have geographical indications and traditional specialities in the European Union designations per European Union schemes of geographical indications and traditional specialties: Protected designation of origin (PDO), Protected geographical indication (PGI) and Traditional specialities guaranteed (TSG). These standards serve to promote and protect names of quality agricultural products and foodstuffs.
Phylogenetic analysis suggests that human ancestors may have invented cooking as far back as 1.8 million to 2.3 million years ago. Re-analysis of burnt bone fragments and plant ashes from the Wonderwerk Cave, South Africa, has provided evidence supporting control of fire by early humans there by 1 million years ago. There is evidence that Homo erectus was cooking their food as early as 500,000 years ago. Evidence for the controlled use of fire by Homo erectus beginning some 400,000 years ago has wide scholarly support. 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. Anthropologists think that widespread cooking fires began about 250,000 years ago, when hearths started appearing.
Saltiness is the taste of alkali metal ions such as sodium and potassium. It is found in almost every food in low to moderate proportions to enhance flavor, although to eat pure salt is regarded as highly unpleasant. There are many different types of salt, with each having a different degree of saltiness, including sea salt, fleur de sel, kosher salt, mined salt, and grey salt. Other than enhancing flavor, its significance is that the body needs and maintains a delicate electrolyte balance, which is the kidney's function. Salt may be iodized, meaning iodine has been added to it, a necessary nutrient that promotes thyroid function. Some canned foods, notably soups or packaged broths, tend to be high in salt as a means of preserving the food longer. Historically salt has long been used as a meat preservative as salt promotes water excretion. Similarly, dried foods also promote food safety.
The Mayo Clinic Diet is the official diet developed by Mayo Clinic, based on research and clinical experience. It focuses on eating healthy foods that taste great and increasing physical activity. It emphasizes that the best way to keep weight off for good is to change your lifestyle and adopt new health habits. This diet can be tailored to your own individual needs and health history — it isn't a one-size-fits-all approach.
Cooking requires applying heat to a food which usually, though not always, chemically changes the molecules, thus changing its flavor, texture, appearance, and nutritional properties. Cooking certain proteins, such as egg whites, meats, and fish, denatures the protein, causing it to firm. There is archaeological evidence of roasted foodstuffs at Homo erectus campsites dating from 420,000 years ago. Boiling as a means of cooking requires a container, and has been practiced at least since the 10th millennium BC with the introduction of pottery.
A negative-calorie food is food that supposedly requires more food energy to be digested than the food provides. Its thermic effect or specific dynamic action – the caloric "cost" of digesting the food – would be greater than its food energy content. Despite its recurring popularity in dieting guides, there is no scientific evidence supporting the idea that any food is calorically negative. While some chilled beverages are calorically negative, the effect is minimal and drinking large amounts of water can be dangerous.
As previously discussed, the body is designed by natural selection to enjoy sweet and fattening foods for evolutionary diets, ideal for hunters and gatherers. Thus, sweet and fattening foods in nature are typically rare and are very pleasurable to eat. In modern times, with advanced technology, enjoyable foods are easily available to consumers. Unfortunately, this promotes obesity in adults and children alike.
^ Smithers, Rebecca (February 10, 2012). "Sainsbury's changes food freezing advice in bid to cut food waste". The Guardian. Retrieved February 10, 2012. Long-standing advice to consumers to freeze food on the day of purchase is to be changed by a leading supermarket chain, as part of a national initiative to further reduce food waste. [...] instead advise customers to freeze food as soon as possible up to the product's 'use by' date. The initiative is backed by the government's waste advisory body, the Waste and Resources Action Programme (Wrap) [...] Bob Martin, food safety expert at the Food Standards Agency, said: "Freezing after the day of purchase shouldn't pose a food safety risk as long as food has been stored in accordance with any instructions provided. [...]"
Food poisoning has been recognized as a disease since as early as Hippocrates. The sale of rancid, contaminated, or adulterated food was commonplace until the 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 are ubiquitous in developed nations today. This was further underpinned by the work of Justus von Liebig, which led to the development of modern food storage and food preservation methods. 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 the Hazard Analysis and Critical Control Points (HACCP), which can identify and eliminate many risks.
Vegetables are a second type of plant matter that is commonly eaten as food. These include root vegetables (potatoes and carrots), bulbs (onion family), leaf vegetables (spinach and lettuce), stem vegetables (bamboo shoots and asparagus), and inflorescence vegetables (globe artichokes and broccoli and other vegetables such as cabbage or cauliflower).