Shelf stable
Shelf stable food is food
Food is any substance consumed to provide nutritional support for the body. It is usually of plant or animal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals...

 of a type that would normally be stored refrigerated but which has been processed
Food processing
Food processing is the set of methods and techniques used to transform raw ingredients into food or to transform food into other forms for consumption by humans or animals either in the home or by the food processing industry...

 so that it can be safely stored in a sealed container at room or ambient temperature for a usefully long shelf life
Shelf life
Shelf life is the length of time that food, drink, medicine, chemicals, and many other perishable items are given before they are considered unsuitable for sale, use, or consumption...

. For instance, the first shelf stable formulation of ranch dressing
Ranch dressing
Ranch dressing is a condiment made of some combination of buttermilk, sour cream, yogurt, mayonnaise, minced green onion, garlic powder, and other seasonings mixed into a sauce. Ranch dressing has been the best-selling salad dressing in the United States since 1992, when it overtook Italian dressing...

, created in 1983, had a shelf life of 150 days.

Various food preservation
Food preservation
Food preservation is the process of treating and handling food to stop or slow down spoilage and thus allow for longer storage....

 and packaging techniques are used to extend a food's shelf life. Decreasing the amount of available water
Water activity
Water activity or aw was developed to account for the intensity with which water associates with various non-aqueous constituents and solids. Simply stated, it is a measure of the energy status of the water in a system...

 in a product, increasing its acidity, or irradiating
Food irradiation
Food irradiation is the process of exposing food to ionizing radiation to destroy microorganisms, bacteria, viruses, or insects that might be present in the food. Further applications include sprout inhibition, delay of ripening, increase of juice yield, and improvement of re-hydration...

or otherwise sterilizing the food and then sealing it in an air-tight container, can all extend a food's shelf life without unacceptably changing its taste or texture.

For some foods alternative ingredients can be used. Common oil
An oil is any substance that is liquid at ambient temperatures and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical oils, and synthetic oils....

s and fat
Fats consist of a wide group of compounds that are generally soluble in organic solvents and generally insoluble in water. Chemically, fats are triglycerides, triesters of glycerol and any of several fatty acids. Fats may be either solid or liquid at room temperature, depending on their structure...

s become rancid
Rancidification is the chemical decomposition of fats, oils and other lipids . When these processes occur in food, undesirable odors and flavors can result. In some cases, however, the flavors can be desirable . In processed meats, these flavors are collectively known as "warmed over flavor"...

 relatively quickly if not refrigerated; replacing them with trans fat
Trans fat
Trans fat is the common name for unsaturated fat with trans-isomer fatty acid. Because the term refers to the configuration of a double carbon-carbon bond, trans fats are sometimes monounsaturated or polyunsaturated, but never saturated....

s delays the onset of rancidity, increasing shelf life. This is a common approach in industrial food production, but recent concerns about health hazards associated with trans fats have led to their prohibition in several jurisdictions. Even where
trans fats are not prohibited, in many places there are new labeling laws (or rules), which require information to be printed on packages, or to be published elsewhere, about the amount of trans fat contained in certain products.
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