Shea butter

Shea butter(/ʃiː/SHEE,/ˈʃiːə/SHEE-ə, or/ʃeɪ/SHAY;Bambara:ߛߌ߮ߕߎߟߎ,romanized:sìtulu) is a fat (triglyceride; mainlyoleic acidandstearic acid) extracted from the nut of the African shea tree (Vitellaria paradoxa).It is ivory in color when raw and commonly dyed yellow withborututuroot orpalm oil. It is widely used in cosmetics as a moisturizer or lotion. It is edible and is used in food preparation in some African countries.It is occasionally mixed with other oils as a substitute for cocoa butter, although the taste is noticeably different.
The English word "shea" comes fromsǐ, the tree's name inBambara.It is known by many local names, such askpakahiliin theDagbani language,taamain theWali language,nkutoinTwi,kaɗeorkaɗanyainHausa,òkwùmáin theIgbo language,òríin theYoruba language, andkaritéin theWolof languageofSenegal.It is also known as Moo-yaa in theAcholilanguage.
The common name isshísuߛ߭ߌ߭ߛߎ(lit. "shea tree") in the Bambara language of Mali. This is the origin of the English word, one pronunciation of which rhymes with "tea"/ʃiː/, although the pronunciation/ʃeɪ/(rhyming with "day") is common, and is listed second in major dictionaries. The tree is calledgharitiin the Wolof language of Senegal, which is the origin of the French name of the tree and the butter,karité.
The shea tree grows naturally in the wild in the drysavannahbelt of West Africa from Senegal in the west toSudanin the east, and onto the foothills of the Ethiopian highlands. It occurs in 21 countries across the African continent, namelyBenin,Burkina Faso,Cameroon,Central African Republic,Chad,Ethiopia,Eritrea,Ghana,Guinea Bissau,Ivory Coast,Mali,Niger,Nigeria,Senegal,Sierra Leone,South Sudan,Sudan,Togo,Uganda,Democratic Republic of the Congo,KenyaandGuinea.
Atestafound at the site of the medieval village of Saouga is evidence of shea butter production by the 14th century.The butter was being imported into Britain by 1846.
Shea butter is composed of five principal fatty acids:palmitic,stearic,oleic,linoleic, andarachidic(see Table below). About 85 to 90% of the fatty acid composition is stearic and oleic acids. The relative proportion of these two fatty acids affects shea butter consistency. The stearic acid gives it a solid consistency, while the oleic acid influences how soft or hard the shea butter is, depending on ambient temperature.
The proportions of stearic and oleic acids in the shea kernels and butter differ across the distribution range of the species. Ugandan shea butter has consistently high oleic acid content, and is liquid at warm ambient temperatures. It fractionizes into liquid and solid phases, and is the source of liquid shea oil. The fatty acid proportion of West African shea butter is much more variable than Ugandan shea butter, with an oleic content of 37 to 55%. Variability can be high even locally, and a tree that produces hard butter can grow with one that produces soft butter.
Nuts are gathered from a wide area for local production, so shea butter consistency is determined by the average fatty acid profile of the population. Within West Africa, shea butter from the Mossi Plateau region ofBurkina Fasohas a higher average stearic acid content, and so is usually harder than shea butter from other West African regions.
A 2014 review characterized and quantified phenolic compounds in shea butter, identifying 10 phenolic compounds, eight of which arecatechins.This study also found that the overall concentration and relative percentages of different phenolic content in shea kernels varied from region to region.The authors hypothesized that the overall concentration of phenols in shea kernels is linked to the level of environmental stress that the trees endure.
Shea butter is mainly used in the cosmetics industry for skin- and hair-related products (lip gloss, lip stick, skin moisturizer creams and emulsions, and hair conditioners for dry and brittle hair).It is also used by soap makers and massage oil manufacturers, typically in small amounts, because it has plenty ofunsaponifiables, and higher amounts result in a softer soap that has less cleaning ability. Some artisan soap makers use shea butter in amounts to 25% – with the European Union regulating the maximum use around 28%, but it is rarely the case in commercially produced soap due to its high cost compared to oils like palm oil or olive oil.
In some African countries such asBenin, shea butter is used as cooking oil,as a waterproofing wax, for hairdressing, for candle-making, and as an ingredient in medicinal ointments. It is used by makers of traditional Africanpercussion instrumentsto increase the durability of wood (such as carveddjembeshells), driedcalabashgourds, and leather tuning straps.
TheUnited States Agency for International Developmentand other companies have suggested a classification system for shea butter, separating it into five grades:
Commercial grades are A, B, and C. The color of raw (grade A) butter ranges from cream (like whipped butter) to grayish yellow. It has a nutty aroma which is removed in the other grades. Grade C is pure white. While the level of vitamin content can be affected by refining, up to 95% of vitamin content can be removed from refined grades (i.e., grade C) of shea butter while reducing contamination levels to undetectable levels.