It can be seen that cocoa butter (as coconut oil or hydrogenated palm oil) is rich in saturated fatty acids and poor in essential fatty acids (n-6 and n-3). A number of plant families have seed fats characterized by low amounts of palmitic, oleic and linoleic acids. These acids have been replaced by lauric (12:0) and myristic (14:0) acids, as well as capric (10:0) and caprylic (8:0) acids. Among Lauracaea, Laurus nobilis fat contains about 58% lauric acid, while among Lythracaea, Cuphea salvadorensis contains about 65% myristic acid, C. calophylla 85% lauric acid, C. koehneana 92% capric acid, and C. pulcherrina 94% caprylic acid (Isbell TA et al., Inform 2003, 14, 513).  
Peanut, olive and rapeseed oils are the richest in monoene (n-9) fatty acids. 
 Rapeseed oil (or colza oil from Brassica sp) was originally available as a high-erucic oil (almost 50% of 22:1n-9) used mainly in the oleochemical industry. Several studies in animal models have shown that erucic acid may have detrimental effects on cardiovascular physiology, therefore, a low erucic acid oil is now produced and can be used safely in the food industry. 
Soya, corn, sunflower and walnut oils are very rich in one diene (n-6) fatty acid, linoleic acid (18:2n-6) while rapeseed, walnut and soya oils are precious sources of one triene (n-3) fatty acid, linolenic acid (18:3n-3).

The seed oils of watercress (Nasturtium) and Honesty (Lunaria annua) have relatively high proportions of  C22:1 (38-48%) and C24:1(22-25%) fatty acids in their triglyceride molecules, these peculiarities make them potentially suitable for production of high-temperature lubricants and engineering nylons. The seeds of Crambe abyssinica (Cruciferae), a cabbage-like annual herb cultivated in Northern Europe, contain an oil high in erucic acid (about 56%).  The seed oil of meadowfoam (Limnanthes alba) contains triglycerides with over 98% fatty acids over 20 carbon atoms. Among them, are found 20:1 n-15 (about 60%), 22:1 n-17 (about 4%) and cis 5, 13 -22:2 (about 17%). Furthermore, this oil is liquid at room temperature even though it is of high molecular weight, it is one of the most stable lipids known, and it is highly resistant to oxidation. Meadowfoam oil has many potential applications in cosmetics, lubricants, waxes, polymers, surfactants, water repellents, and in textile and leather manufacturing

Positional distribution of major fatty acids in triglycerides of some plant oils

The composition and structure of natural vegetal oils may be modified by chemical or enzymatic processes known as interesterification or hydrogenation.

Some seed oils contain also hydroxy fatty acids and are known as hydroxy acid oils. Thus, castor bean (Ricinus communis) produces a seed oil which contains about 90% ricinoleic acid (hydroxy oleic acid) and 1-2% dihydroxystearic acid. Glycerides of Strophantus oils contain 6-15% 9-hydroxy-octadec-12-enoic acid. Coriaria seed oil contains 66-68% of a rare fatty acid, coriolic acid (13-hydroxy-9c,11t-octadecadienoic acid). Seed oil of Cardamine impatiens contains C18, C20, C22 and C24 dihydroxy acids in which one of the hydroxyl groups is acetylated, thus forming triglyceride molecules named estolide triglycerides.
In one of these molecules found in seed oil from Sebastiana commersoniana (Euphorbiaceae) an hydroxy allenic acid was discovered (Spitzer V et al. Lipids 1997, 32, 549).  

Some seed oils contain epoxy fatty acids and are known as epoxy acid oils. Thus, vernolic acid (cis-12,13-epoxy-cis-9-octadecenoic acid) is found in Vernonia, Euphorbia and Cephalocroton.

Curiously, acetic acid was shown to be a component of natural triglycerides in some plant species. It is known that Celastraceae, Lardizabalaceae, Ranunculaceae and Rosaceae plants contain monoaceto triglycerides (Kleimann R et al., Lipids 1967, 2, 473). 2- or 3-Acetyl glycerides (liliosides) were isolated from Lilium longiflorum (Kaneda M et al., Tetrahedron Lett 1974, 3937).  The seed oil of Impatiens roylei and Euonymus verrucosus contain as major triglyceride species the sn-glycerol-1,2-diacyl-3-acetins (Kleiman R et al., Lipids 1966, 1, 286; Bagby MO et al., Biochim Biophys Acta 1967, 137, 475). Monoacetyldiglycerides were also isolated from an animal tissue, bovine udder. 1,2-Diacyl 3-acetin, distearoacetin, stearo-oleaoacetin and stearo-linoleo-acetin have been isolated from lipids of the insect Icerya purchasi (Hashimoto A et al., Jap J Appl Ent Zool 1974, 18, 121).

In some rare vegetals, phenolic triacylglycerols have been described. Thus, phenolic acid triglycerides were isolated in the bud excretion of Populus lasiocarpa, a tree native in China (Asakawa Y et al., Phytochemistry 1976, 15, 811). These lipids were identified as 1,3-di-p-coumaryl-2-acetyl-glycerol (see fig below). A similar compound with methylated coumaryl groups was also identified. Several other phenolic triglycerides have been isolated from lipophilic excretion of winter buds of many species of Populus : 1-p-coumaryl-3-caffeyl-2-acetyl glycerol, 1,3-di-caffeyl-2-acetyl glycerol (Asakawa Y et al., Phytochemistry 1977, 16, 1791).

A translation table of seed oils (6 languages) including the botanical sources may be found in a page of the AOCS Analytical Divisions.

An important database for seed oil fatty acids established by the Institute for Chemistry and Physics of Lipids in Műnster is now electronically searchable : the Database SOFA. 
This internet database allows to search for plant species, genera and families, for individual fatty acids (start by adding an asterisk after each entry) and combinations of fatty acids in their seed oils, and for their percentage contents. It contains literature references and numerous unpublished data. Moreover, fatty acid partial structures or functional groups can also be searched for, using the "delta-notation" system of chemists as described above. The use of the database is mostly straightforward and self-explanatory but several examples for search operations have been published to help anybody interested in seed oils and their fatty acid composition (Aitzetmüller K et al., Eur J Lipid Sci Technol 2003, 105, 92). 

The fatty acid profiles of 80 vegetable oils with regard to their nutritional potential has been reported (Dubois V et al., Eur J Lipid Sci Technol 2007, 109, 710). Triacylglycerols profiling of 26 plant oils important in food industry, dietetics and cosmetics has been done, reporting the distribution of 264 triacylglycerol species consisting of 28 fatty acids (Lisa M et al., J Chromatogr A 2008, 1198-1199, 115).

Since about 1990, genetically modified oils have been developed using either mutation/selection breeding or the tools of biotechnology and represent some of the most significant new products developed for the oils and fats industry . Many of these new oils possess fatty acid contents that are unique to the plant in which they have been developed. Thus, they convey different functional and/or nutritional characteristics compared to the classic or natural types. Genetically modified oils fall into two main categories. The first group has been designed to give products with enhanced oxidative stability. These oils are targeted mainly to salad dressing or frying applications and are best represented by the high oleate and low linolenate types. The second general group is characterized by oils with altered levels of saturated fatty acids. In the future, it may be expected that oils will be genetically created possessing novel fatty acyl substitutions, such as hydroxyl or epoxy groups, as well as alkyne or conjugated double bonds. These types represent potential alternatives to industrial oils derived currently from undomesticated species. An extensive review of genetically modified oils and the utilization of analytical procedures for characterizing these oils may be consulted with interest (Hazebroek JP, Prog Lipid Res 2000, 39, 477).

According to OIL WORLD, ten oilseeds can be divided into three groups based on their levels of production. Soybean dominates representing over 30% of the ten seeds. This is followed by four seeds (rapeseed/canola, cottonseed, sunflower and groundnut, each in the range 3-13% of the total) making up a further 40% and five others (corn, palm kernel, coprah, sesame, linseed, and castor), each in the range 0.5-2% of the total.
The expected relative values of world seed oil production in 2003-2004 for ten major sources  are given below:

The world oilseed production is expected to be about 340 million tons for 2003-2004 and jumped by an average 13 million tons per year during the last 10 years. The world supply of vegetable oils from the ten major sources in 2004-2005 is about 110 million tons 

Recent world statistics for the production of main vegetable oils may be found at the FEDIOL web site.

Oil sources can be easily sorted according to the importance and  use of the extracted oil.

Thus, information on near the totality of oil sources are distributed below among 5 groups: