Unsaponifiable material

The unsaponifiable matter in peanut oil is mainly sterols (largely fi-sitostcrol and campesterol). 

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Distillation. Most fatty acids are distilled to produce high quaHty products having exceUent color and a low level of impurities. Distillation removes odor bodies and low boiling unsaponifiable material in a light ends or heads fraction, and higher boiling material such as polymerized material, triglycerides, color bodies, and heavy decomposition products are removed as a bottoms or pitch fraction. The middle fractions sometimes can be used as is, or they can be fractionated (separated) into relatively pure materials such as lauric, myristic, palmitic, and stearic acids. 

Tall Oil Fatty acids and some unsaponifiable material obtained as a major byproduct from the sulfite-pulping process of wood. 

In a 12-I. round-bottom flask, fitted with an efficient mechanical stirrer, is placed 5 l. of a 5 per cent solution of sodium hydroxide (6.25 moles). To this is added the crude ethyl w-butylaceto-acetate (about 925 g.) (p. 36) obtained from 5 moles of ethyl acetoacetate. The mixture is stirred at room temperature for four hours, during which time the mono-substituted acetoacetic ester is completely saponified and passes into solution. The mixture is then allowed to stand until the unsaponified material separates completely as an oily layer. The aqueous layer is separated (Note r) and transferred to a flask provided with a stopper fitted with a separatory funnel and a large bent glass tube leading to a condenser set for distillation. 

A mixture of petroleum ether/diethyl ether (1 + 1) is suitable for extracting vitamin D from the unsaponifiable material and allows vitamins A and D to be coextracted. For the determination of vitamin D alone in fortified milks, margarine, and infant formulas, Thompson et al. (70) extracted the unsaponifiable matter three times with hexane in the presence of a 6 4 ratio of water to ethanol. The combined hexane layers were then washed with 55% aqueous ethanol, after the initial 5% aqueous KOH and water washes, to remove material, including 25-hydroxyvitamin D, that was more polar than vitamin D. This extraction process was based on partition studies that showed that insignificant amounts of vitamin D were extracted from hexane by aqueous ethanol when the ratio of ethanol to water was less than 6 4. 

Saponification of the sample simplifies the analysis by converting the vitamin A esters to retinol. The unsaponifiable material is extracted with hexane, or a predominantly hexane solvent mixture, which is compatible with the nonpolar mobile phase (146,153,156). In vitamin A-fortified foods there is no need to concentrate the unsaponifiable extract—an aliquot can be injected directly into the chromatograph (153). 

Sato, Y. and Tsuchiya, Y. (1970). Studies on the lipids of Ruvettus pretiosus. n. The composition of the unsaponifiable material and die purgative action of the oils on die mouse. Tohoku Journal of Agricultural Research 21,176-182. 

In India, small seeds generally had higher oil content than larger seeds and the main characteristics were specific gravity (15°C), 0.9304 refractive index (15°C), 1.4795 optical rotation, +35° saponification value, 181.2 iodine value (Wijs), 99 unsaponified material, 3.7%. The expressed oil is classified as semi-drying and is a source of lauric and adipic acids (Weiss, 2002). Table 12.4 gives the average physico-chemical properties of fennel volatile oil. 

The neutral or unsaponifiable materials present in tall oil include anhydrides, pheno-lics, diterpene aldehydes and alcohols, stil-benes, and steroids. In the neutral fraction of southern pine tall oil soap, 80 compounds have been identified. They include 25.1 percent sistosterol and a total of 32.4 percent steroids. The sistosterol content of crude tall oil is 2-3 percent and is the main component of the neutral fraction. 

Avocado Persea americana). The avocado grows in tropical and subtropical countries between 40°N and 40°S and is available particularly from California, Florida, Israel, New Zealand, and South Africa. Like the palm and the olive, lipid is concentrated in the fruit pulp (4—25%) from which it can be pressed. There is very little oil in the seed (2%). The oil is used widely in cosmetic products as it is easily absorbed by the skin, and its unsaponifiable material is reported to provide some protection from the sun. It is also available as a high-oleic speciality oil for food use. It is rich in chlorophyll, making it green before processing. It contains 16 0 (10-20%), 18 1 (60-70%), and 18 2 (10-15%) as its major fatty acids. Its unsaponifiable matter, total sterol, and tocopherol levels have been reported (74-78). 

Studies on Pinus species have shown that the nature and amount of extractives depend upon the percentage of heartwood present and thus on tree age. In Piims radiata, heartwood starts forming once the trees are about 12 to 15 years old. Heartwood extractives occur in greatest amount in inner growth rings near the pith (Uprichard, 1971 Lloyd, 1978) especially in the butt log of mature trees (Table 2.5). The high level of resin in the inner zone appears due to a process of enrichment with sapwood extractives via the transverse resin canals (Harris, 1965). Resin acids predominate in heartwood and comprise from 70-80% of total extractives, however in sapwood there are approximately equal amounts of resin acids and fatty acids (Table 2.6). An important feature of the resin constituents of pines is that a mixture of resin acids in turpentine occur in the resin canals, and the fatty acid esters and unsaponifiable materials occur in the ray parenchyma resin. In some processes, for example refiner mechanical pulping some separation of these chemical components can occur. 

Figure 2.16. Some important extractives of softwoods, (a) A mixture of resin acids in turpentine is present in resin canals of Pinus radiata. (b) Ray parenchyma resin of Pinus radiata consists mainly of fatty acid esters and unsaponifiable materials (a major component of which is 3-sitosterol). (c) Polyphenolics found in Pinus radiata heartwood. (d) Some polyphenols that are significant in certain other softwoods.

The unsaponifiable material (1-3%) consists mainly of sterols, tocopherols and sesame lignans. For four cultivated species of S. indicum, the level of unsaponifiable material has been reported to be 1.4—1.8% (Kamal-Eldin and Appelqvist 1994b). The sesame oils from these species contained total sterols (0.51-0.76%), including desmethyl sterols (85-89%), monomethyl sterols (9-11%) and triterpene alcohols (dimethyl sterols) (2-4%) respectively. (1-Sitosterol (62-67%), campesterol (15-20%), stigmasterol (5-8%) and A5-avenasterol (7-10%) are the major sterols present in both free and esterified forms. The monomethyl sterols, namely gramisterol, citrostadienol and obtusi-foliol, were present mainly as esters. The total sterols contained 65% in free and 35% in esterified form. Composition (% wt) data of the desmethyl sterols, monomethyl sterols and dimethyl sterols (tritepene alcohols) of four Sesamum species are listed in Table 11.4. Tocopherols of crude sesame oils are generally... 

Refining of soybean oil is practiced as a purifying treatment designed principally to remove FFA while reducing the phosphatides or gums, coloring matter, insoluble matter, settlings, and miscellaneous unsaponifiable materials. Failure to remove these impurities causes the oil to foam, darken, smoke, and become cloudy when heated. The time-honored or conventional method for removal of the impurities from the oils is by the use of a solution of sodium hydroxide to react with the FFA to produce... 

This distribution of fatty acids is also of some interest to nutritionists as the effects of fatty acids in rats can be modified by redistributing the fats by interesterification (Mukherjee and Sengupta, 1981). As much as 40% of the dietary fat consumed in the Federal German Republic in recent years has been subjected to transesterification processes such as described by Perron and Broncy (1978) and Monseigny eta/. (1979). This makes surveys of composition of edible fats rather difficult in terms of fatty acids (Heckers and Melcher, 1978), and enforces the examination of unsaponifiable materials to discover the original oil composition (Strocchi, 1981). 

Terpenic and aliphatic alcohols are also present in grapeseed oil from about 7 to 24% of the unsaponifiable matter. The straight chain alcohols from 20 to 28 carbons have been identified as well as p-amyrin, cycloartenol, a-amyrin and 24-methylenecycloartanol (Capella et al., 1979b). Methyl sterols are present from 7 to 13% of the unsaponihables and contain among others obtusifoliol, gramisterol and citrostadienol. Sterol and terpenic dialcohols comprise up to about 45% of the unsaponifiable material. The major sterols identified are campesterol, stigmasterol (about... 

This fat has a high level of unsaponifiable material (5-7%) which is mainly triterpenes. It is used in cosmetics especially for suntan lotions. 

In the past, when softwoods were the source of most pulpwood, the major problems caused by extractives were those of pitch, largely resulting from the resin and fatty acids and unsaponifiable materials. Next came the problems caused by the discoloration of pulp due to the presence of polyphenols in hardwoods, notably eucalypts. Now with the increasing use of relatively unfamiliar tropical hardwoods, some of which contain large amounts of extractives, new problems are arising due to polyphenols and a group of resins different from those previously encountered. Differences in their behavior include difficulties in their removal by bleaching and in their removal from pulp mill equipment (e.g., 99). New methods need to be devised to minimize their influence and overcome these difficulties. 

Industry uses a number of analytical methods to characterize oils and fats, in terms of a number of parameters which include moisture, titer (solidification point), free fatty acid, unsaponifiable material, iodine value, peroxide value, and color. Moisture content of the oils and fats is an important measure for storage stability at elevated temperature because it facilitates hydrolysis which in turn impacts odor and color quality. Titer is a measure of the temperature at which the material begins to solidify, signifying the minimum temperature at which the material can be stored or pumped as a fluid. Free fatty acid is a measure of the level of hydrolysis the oils and fats have undergone. Increased fatty acid content usually negatively impacts product color stability because fatty acids are more susceptible to oxidation. Unsaponifiable material is a measure of the nontriglyceride fatty material present, which affects the soap yield of the material. The iodine value is a measure of the amount of unsaturation present in the oils and fats. Peroxide value is a measure of the... 

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