Helpful Olive Oil, Vegetable Oil Education - Common Terms

Antioxidant

Any material that is added to a fat that helps to provide greater stability than the fat provides by itself.  The antioxidant prevents the reaction of fat with oxygen thus allowing for a longer oil life span.

Bleaching

Oil is filtered with acidified clays; this removes color pigments and some flavor from the oil.

Cold Pressed

This is a mechanical extraction of the oil from the seed using a stone or centrifuge.  When the oil is extracted from the seed it is at a temperature of under 120 degrees.

Cold Test

A test performed to find how readily oil will solidify in cold temperatures.  The oil is held in water at a temperature 32° F the amount of time it takes before the oil begins to cloud is know as the “cold test hours.”

Degumming

A process using a water washing step that removes phospholipids from vegetable oil

Deodorized

When deodorized the oil is steam processed in a vacuum chamber.  This process removes free fatty acids along with flavor and odors and creates bland oil.

Dewaxing

The process in which solid fats are removed from liquid oil.

Expeller Pressed

Expeller pressing is a method used to extract oil with a mechanical press rather than a chemical extracting process.  When oil is expeller pressed there is no chemical residues resulting in a cleaner more pure oil, this results in a more natural color and flavor.

An expeller press is a screw type machine which presses the seed through a caged section.  The pressure from the press crushes the seed creating the oil which seeps through the caged area.  What is left of the seed is removed and the process starts again from the beginning.

Fatty Acids

Naturally occurring strongly linked carbon and hydrogen atoms in a chain like structure.  At the end of the chain a reactive acid group of carbon, hydrogen, and oxygen can be found.  This group reacts with glycerol to create a fatty acid which is a primary part of the triglyceride fat molecule. 

Genetically Modified Organism (GMO)

A living organism, the genetic makeup of which has been altered.

High Oleic

High Oleic oils use a higher quality seed for their oil which allows the oils to stay stable at high temperatures.

Hydrogenization

The process of chemically adding hydrogen to a natural fat. This process allows the oil to have a longer fry life by reducing the rancidity process. 

Linoleic Acid

One of two polyunsaturated fatty acids found in soybean oil. These polyunsaturated fats can help reduce the levels of cholesterol.

Linolenic Acid

An omega-3 polyunsaturated fat found in soybean oil and other seed derived oils.

Monounsaturated Fatty Acid

A type of unsaturated fatty acid in which the chain of carbon atoms is missing one pair of hydrogen atoms.  This type of fatty acid aids in stability and is found in many vegetable oils.

Oleic Acid

A monounsaturated fatty acid that contributes to the stability of oil, and helps to extend shelf life.

Organic

Term used to describe the method a product was produced.  The ingredients in the product must be grown in a process that avoids all synthetic materials used for farming.

Palmitic Acid

A stable saturated fatty acid, which is used in frying.

Polyunsaturated Fatty Acids

A type of unsaturated fatty acid in which the chain of carbon atoms is missing two or more pairs.

Rancidity

The point in which the fat oxidation in oil has reached the point in which there is an off-flavor and odor.

Refined Oils

This refers to the processes the oil must go through to make the oil salad grade. First treatment is the Alkali treatment which removes impurities such as gums non fatty materials and acidic pigments.

Trans Fatty Acid

Unsaturated fatty acids that have at least one double bond in the transfiguration.  This process is used with oil to lengthen the oils fry life.  Research has shown Trans fatty acid helps to raise LDL cholesterol.  Since 2006 the U.S. FDA has mandated that all food produced in the United States must list Trans fat contents.

Unrefined Oils

This is oil that has been filtered but not refined, bleached, or deodorized.  Unrefined oil delivers a stronger flavor and odor. 

Winterized

This process cold filters the oil and uses a fractional crystallization process which removes waxes and saturated glycerides.  This process helps to prevent the cloudiness of the oil.