Carnuba wax consists chiefly of myricyl cerotate (M<sub>W</sub> 817.4) and small quantities of free cerotic acid (C<sub>26</sub>H<sub>52</sub>O<sub>2</sub>, Mw 396.7) an...Carnuba wax consists chiefly of myricyl cerotate (M<sub>W</sub> 817.4) and small quantities of free cerotic acid (C<sub>26</sub>H<sub>52</sub>O<sub>2</sub>, Mw 396.7) and myricyl alcohol (C<sub>30</sub>H<sub>62</sub>O, mp 90°C). Of the two common extraction solvents, ethyl ether or petroleum ether, Lewkowitsch prefers the former. Concerning separation of phases, he advocates addition of small amounts of alcohol or caustic, and he also states that formation of a flocculant layer between the aqueous layer and the solvent does not interfere with the correct estimation of the unsaponifiable matter. These statements were not corroborated in the hands of this chemist. The “Unsaponifiable Matter” in oils or and fats, which consist mainly of hydrocarbons, sterols and aliphatic alcohols of high molecular mass that are not saponifiable by alkali hydroxides but are soluble in the ordinary fat solvents, and to products of saponification that are soluble in such solvents. Carnuba wax, a rather expensive wax, may be adulterated with less expensive paraffin by dishonest merchants. ASTM has a method for determining paraffinic material in carnuba wax. It uses heptanes at its boiling point to dissolve the wax, apply it to a silica gel column, and elute only the nonpolar (i.e. alkane) material. The method has the disadvantage of using a large volume of haptane, nor is it called for by either US Pharmacopeia/National Formulary (USP/NF) or Food Chemicals Codex (FCC). The test for unsaponifiable matter on pure carnuba wax will yield a result of 50.0% - 55.0%, while a higher result will betray the presence of paraffin adulterants.展开更多
Palm fatty acid distillate (PFAD), a by-product of deodorization in palm oil refining, contains about 0.7%-1% vitamin E. The advantage of PFAD over other vitamin E sources is higher amount of tocotrienols than that ...Palm fatty acid distillate (PFAD), a by-product of deodorization in palm oil refining, contains about 0.7%-1% vitamin E. The advantage of PFAD over other vitamin E sources is higher amount of tocotrienols than that of tocopherols. Vitamin E purification of unsaponiable matter of PFAD was aimed to remove other impurities to obtain high vitamin E concentration, mainly tocotrienols. This research used low temperature solvent crystallization to purify vitamin E. To optimize response of vitamin concentration, a response surface method was applied with three factors, i.e., the ratio between solvent and unsaponifiable matter (A), crystallization temperature (B), and crystallization time (C). The relation of three factors was quadratic with equation Y = -128.54361 + 41.33904A - 0.87995B + 1.58941C + 0.00290AB - 0.044324AC + 0.00120BC - 3.33113A2 - 0.039535B2 - 0.02710C2. The optimum crystallization condition was obtained at ratio of solventto unsaponifiable matter of 6.04:1, crystallization temperature of-10.54 ℃, and crystallization time of 24.16 hours. Vitamin E enriched fraction from optimum crystallization conditions contained vitamin E of 20.13% (w/w).展开更多
文摘Carnuba wax consists chiefly of myricyl cerotate (M<sub>W</sub> 817.4) and small quantities of free cerotic acid (C<sub>26</sub>H<sub>52</sub>O<sub>2</sub>, Mw 396.7) and myricyl alcohol (C<sub>30</sub>H<sub>62</sub>O, mp 90°C). Of the two common extraction solvents, ethyl ether or petroleum ether, Lewkowitsch prefers the former. Concerning separation of phases, he advocates addition of small amounts of alcohol or caustic, and he also states that formation of a flocculant layer between the aqueous layer and the solvent does not interfere with the correct estimation of the unsaponifiable matter. These statements were not corroborated in the hands of this chemist. The “Unsaponifiable Matter” in oils or and fats, which consist mainly of hydrocarbons, sterols and aliphatic alcohols of high molecular mass that are not saponifiable by alkali hydroxides but are soluble in the ordinary fat solvents, and to products of saponification that are soluble in such solvents. Carnuba wax, a rather expensive wax, may be adulterated with less expensive paraffin by dishonest merchants. ASTM has a method for determining paraffinic material in carnuba wax. It uses heptanes at its boiling point to dissolve the wax, apply it to a silica gel column, and elute only the nonpolar (i.e. alkane) material. The method has the disadvantage of using a large volume of haptane, nor is it called for by either US Pharmacopeia/National Formulary (USP/NF) or Food Chemicals Codex (FCC). The test for unsaponifiable matter on pure carnuba wax will yield a result of 50.0% - 55.0%, while a higher result will betray the presence of paraffin adulterants.
文摘Palm fatty acid distillate (PFAD), a by-product of deodorization in palm oil refining, contains about 0.7%-1% vitamin E. The advantage of PFAD over other vitamin E sources is higher amount of tocotrienols than that of tocopherols. Vitamin E purification of unsaponiable matter of PFAD was aimed to remove other impurities to obtain high vitamin E concentration, mainly tocotrienols. This research used low temperature solvent crystallization to purify vitamin E. To optimize response of vitamin concentration, a response surface method was applied with three factors, i.e., the ratio between solvent and unsaponifiable matter (A), crystallization temperature (B), and crystallization time (C). The relation of three factors was quadratic with equation Y = -128.54361 + 41.33904A - 0.87995B + 1.58941C + 0.00290AB - 0.044324AC + 0.00120BC - 3.33113A2 - 0.039535B2 - 0.02710C2. The optimum crystallization condition was obtained at ratio of solventto unsaponifiable matter of 6.04:1, crystallization temperature of-10.54 ℃, and crystallization time of 24.16 hours. Vitamin E enriched fraction from optimum crystallization conditions contained vitamin E of 20.13% (w/w).