Food preservation includes processes that make food more resistant to microorganism growth and slow the oxidation of fats. This slows down the decomposition and rancidification process. Food preservation may also include processes that inhibit visual deterioration, such as the enzymatic browning reaction in apples after they are cut during food preparation. By preserving food, food waste can be reduced, which is an important way to decrease production costs and increase the efficiency of food systems, improve food security and nutrition and contribute towards environmental sustainability. For instance, it can reduce the environmental impact of food production.
A preservative is a substance or a chemical that is added to products such as food products, beverages, pharmaceutical drugs, paints, biological samples, cosmetics, wood, and many other products to prevent decomposition by microbial growth or by undesirable chemical changes. In general, preservation is implemented in two modes, chemical and physical. Chemical preservation entails adding chemical compounds to the product. Physical preservation entails processes such as refrigeration or drying. Preservative food additives reduce the risk of foodborne infections, decrease microbial spoilage, and preserve fresh attributes and nutritional quality. Some physical techniques for food preservation include dehydration, UV-C radiation, freeze-drying, and refrigeration. Chemical preservation and physical preservation techniques are sometimes combined.
In food processing, brining is treating food with brine or coarse salt which preserves and seasons the food while enhancing tenderness and flavor with additions such as herbs, spices, sugar, caramel or vinegar. Meat and fish are typically brined for less than twenty-four hours while vegetables, cheeses and fruit are brined in a much longer process known as pickling. Brining is similar to marination, except that a marinade usually includes a significant amount of acid, such as vinegar or citrus juice. Brining is also similar to curing, which usually involves significantly drying the food, and is done over a much longer time period.
Food drying is a method of food preservation in which food is dried. Drying inhibits the growth of bacteria, yeasts, and mold through the removal of water. Dehydration has been used widely for this purpose since ancient times; the earliest known practice is 12,000 B.C. by inhabitants of the modern Middle East and Asia regions. Water is traditionally removed through evaporation by using methods such as air drying, sun drying, smoking or wind drying, although today electric food dehydrators or freeze-drying can be used to speed the drying process and ensure more consistent results.
Jerky or “charqui” is lean trimmed meat cut into strips and dehydrated to prevent spoilage. Normally, this drying includes the addition of salt to prevent bacteria growth. The word "jerky" derives from the Quechua word ch'arki which means "dried, salted meat".
Smoked salmon is a preparation of salmon, typically a fillet that has been cured and hot or cold smoked.
Dried fruit is fruit from which the majority of the original water content has been removed either naturally, through sun drying, or through the use of specialized dryers or dehydrators. Dried fruit has a long tradition of use dating back to the fourth millennium BC in Mesopotamia, and is prized because of its sweet taste, nutritive value, and long shelf life.
A humectant is a hygroscopic (water-absorbing) substance used to keep things moist. They are used in many products, including food, cosmetics, medicines and pesticides. When used as a food additive, a humectant has the effect of keeping moisture in the food. Humectants are sometimes used as a component of antistatic coatings for plastics.
Sodium erythorbate (C6H7NaO6) is a food additive used predominantly in meats, poultry, and soft drinks. Chemically, it is the sodium salt of erythorbic acid. When used in processed meat such as hot dogs and beef sticks, it increases the rate at which nitrite reduces to nitric oxide, thus facilitating a faster cure and retaining the pink coloring. As an antioxidant structurally related to vitamin C, it helps improve flavor stability and prevents the formation of carcinogenic nitrosamines. When used as a food additive, its E number is E316. The use of erythorbic acid and sodium erythorbate as a food preservative has increased greatly since the U.S. Food and Drug Administration banned the use of sulfites as preservatives in foods intended to be eaten fresh (such as ingredients for fresh salads) and as food processors have responded to the fact that some people are allergic to sulfites. It can also be found in bologna, and is occasionally used in beverages, baked goods, and potato salad. Sodium erythorbate is produced from sugars derived from different sources, such as beets, sugarcane, and corn. Sodium erythorbate is usually produced via a fermentation process from D-glucose by Pseudomonas fluorescens bacteria. Most syntheses proceed through the 2-keto-D-gluconic acid intermediate. An urban myth claims that sodium erythorbate is made from ground earthworms; however, there is no truth to the myth. It is thought that the origin of the legend comes from the similarity of the chemical name to the words earthworm and bait.
Charcuterie is a branch of French cuisine devoted to prepared meat products, such as bacon, ham, sausage, terrines, galantines, ballotines, pâtés, and confit, primarily from pork.
Curing is any of various food preservation and flavoring processes of foods such as meat, fish and vegetables, by the addition of salt, with the aim of drawing moisture out of the food by the process of osmosis. Because curing increases the solute concentration in the food and hence decreases its water potential, the food becomes inhospitable for the microbe growth that causes food spoilage. Curing can be traced back to antiquity, and was the primary method of preserving meat and fish until the late 19th century. Dehydration was the earliest form of food curing. Many curing processes also involve smoking, spicing, cooking, or the addition of combinations of sugar, nitrate, and nitrite.
Disodium pyrophosphate or sodium acid pyrophosphate (SAPP) is an inorganic compound with the chemical formula Na2H2P2O7. It consists of sodium cations (Na+) and dihydrogen pyrophosphate anions (H2P2O2−7). It is a white, water-soluble solid that serves as a buffering and chelating agent, with many applications in the food industry. When crystallized from water, it forms a hexahydrate, but it dehydrates above room temperature. Pyrophosphate is a polyvalent anion with a high affinity for polyvalent cations, e.g. Ca2+.
Cured fish is fish which has been cured by subjecting it to fermentation, pickling, smoking, or some combination of these before it is eaten. These food preservation processes can include adding salt, nitrates, nitrite or sugar, can involve smoking and flavoring the fish, and may include cooking it. The earliest form of curing fish was dehydration. Other methods, such as smoking fish or salt-curing also go back for thousands of years. The term "cure" is derived from the Latin curare, meaning to take care of. It was first recorded in reference to fish in 1743.
Fish preservation is the method of increasing the shelf life of fish and other fish products by applying the principles of different branches of science in order to keep the fish, after it has landed, in a condition wholesome and fit for human consumption. Ancient methods of preserving fish included drying, salting, pickling and smoking. All of these techniques are still used today but the more modern techniques of freezing and canning have taken on a large importance.
Osmotic dehydration is an operation used for the partial removal of water from plant tissues by immersion in a hypertonic (osmotic) solution.
Hurdle technology is a method of ensuring that pathogens in food products can be eliminated or controlled. This means the food products will be safe for consumption, and their shelf life will be extended. Hurdle technology usually works by combining more than one approach. These approaches can be thought of as "hurdles" the pathogen has to overcome if it is to remain active in the food. The right combination of hurdles can ensure all pathogens are eliminated or rendered harmless in the final product.
Bakkwa, also known as rougan, is a Chinese salty-sweet dried meat product similar to jerky.
Wine preservatives are used to preserve the quality and shelf life of bottled wine without affecting its taste. Specifically, they are used to prevent oxidation and bacterial spoilage by inhibiting microbial activity.
