Phytosterols commercial sources

The proximate composition of almond includes 50.6% lipid, 21.3% protein, 19.7% carbohydrate, 5.3% water, and 3.1% ash (w/w) (1). The most common method for producing almond oil is hexane extraction that affords high oil yields, however, cold pressing is another commercially used procedure for almond oil production (8). Shi et al. (8) assessed the fatty acid composition of almond oil oleic acid was major fatty acid present (68%), followed by hnoleic acid (25%), palmitic acid (4.7%), and small amounts (<2.3%) of palmitoleic, stearic, and ara-chidic acids (Table 1). Almond oil is also a rich source of a-tocopherol (around 390 mg/kg) and contains trace amounts of other tocopherol isomers as well as phyl-loquinone (70pg/kg) (1). Almond oil contains 2.6g/kg phytosterols, mainly p-sitosterol, with trace amounts of stigmasterol and campesterol (1). 

Both phytosterols and tocopherols are co-extracted with oil and partially removed during soybean oil refining. The refining by-product is one of the important sources for commercial phytosterol and tocopherol production. 

Sterols are synthesized in both plants and animals. Sterols and their derivatives, such as hormones and vitamin D2, perform various important functions in living organisms depending on their structure. Consequently, sterol products can be derived from several sources. Plant sterols, or phytosterols, are obtained from the unsaponifiable fraction of vegetable oils and fats. The amount of sterol, as well as its composition including fraction of unsaponifiable portion of the respective oil and fats, depends on the raw materials and is characteristic of the particular base material (Table 1). Soya oil represents a widely available source for commercial production of phytosterols. The unsaponifiable portion is separated into a sterol fraction and a tocopherol fraction. A small amount of tocopherol is usually left in the sterol fraction (approximately 4%), which acts as a natural antioxidant in the final product [2]. Plant sterols are also obtained from the black-liquor soap skimming in commercial pulping of wood. The neutral fraction of this so-called tall oil is relatively rich in sterols (approximately 32% of the neutral fraction [3]), and the sterol... 

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