There is no doubt that Earth is a generous planet; nearly everything we require for survival comes from nature; cooking oil, for example, is one of the valuable assets hidden among the abundant natural resources. 

The oil plant is where the oil comes from; it can be anything from a tree like palm to a herb like flax or even a fungus. Oil is extracted primarily from plant seeds, but it is also extracted from the fleshy part of the fruit, as in the olive and oil palm. Most plant-based oils can be used as cooking oil or to produce fuel and diesel. It is estimated that approximately 90% of palm oil is consumed for food, with the remaining 10% consumed for industrial purposes such as cosmetics, fuel, and diesel. Palm, soybean, rapeseed, and sunflower seed are the most common types of oil.

However, plant-based oil was not the first cooking oil discovered by humans. It is thought that people began to use animal fat around 25,000 BC, shortly after the discovery of fire. Soy oil was not invented until 2,000 BC by the Chinese and Japanese. Europeans in the continent's south are thought to have begun producing olive oil in 4,000 BC.

Many plant-based oils are now considered good substitutes for animal fat due to their high unsaturated fat content, which is beneficial to people's health. Soy soil is a classic example. Others with a high smoking point are also considered healthy, such as corn, safflower, palm, and sunflower oil.

Oil isn't the only golden product that comes from plant seeds. Following the extraction of the oil from the oilseeds, the residual is an important by-product that frequently determines the value of an oil crop. This meal is typically fed to livestock and poultry; if poisonous, such as castor beans and tung nuts, it is used as fertilizer.

(All photos via VCG.)

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