Facile purification of tocopherols from soybean oil deodorizer distillate in high yield using lipase

Tocopherols have been purified from deodorizer distillate produced in the final deodorization step of vegetable oil refining by a process including molecular distillation. Deodorizer distillate contains mainly tocopherols, sterols, and free fatty acids (FFA); the presence of sterols hinders tocopherol purification in good yield. We found that Candida rugosa lipase recognized sterols as substrates but not tocopherols, and that esterification of sterols with FFA could be effected with negligible influence of water content. Enzymatic esterification of sterols with FFA was thus used as a step in tocopherol purification. High boiling point substances including steryl esters were removed from soybean oil deodorizer distillate by distillation, and the resulting distillate (soybean oil deodorizer distillate tocopherol concentrate; SODDTC) was used as a starting material for tocopherol purification. Several factors affecting esterification of sterols were investigated, and the reaction conditions were determined as follows: A mixture of SODDTC and water (4∶1, w/w) was stirred at 35°C for 24 h with 200 U of Candida lipase per 1 g of the reaction mixture. Under these conditions, approximately 80% of sterols was esterified, but tocopherols were not esterified. After the reaction, tocopherols and FFA were recovered as a distillate by molecular distillation of the oil layer. To enhance further removal of the remaining sterols, the lipase-catalyzed reaction was repeated on the distillate under the same reaction conditions. As a result, more than 95% of the sterols was esterified in total. The resulting reaction mixture was fractionated to four distillates and one residue. The main distillate fraction contained 65 wt% tocopherols with low contents of FFA and sterols. In addition, the residue fraction contained high-purity steryl esters. Because the process presented in this study includes only organic solvent-free enzymatic reaction and molecular distillation, it is feasible as a new industrial purification method of tocopherols. This work was presented at the Biocatalysis symposium in April 2000, held at the 91st Annual Meeting and Expo of the American Oil Chemists Society, San Diego, CA.     

Tall oil

Summary Tall oil processing is a relatively new and rapidly growing industry. Based on a stable supply of raw material from the kraft paper industry, it provides an important source of rosin and fatty acid products. The processes most generally employed in the United States are acid refining, distillation, and separation by fractional distillation. Tall oil refining techniques have advanced to the point where fatty acids substantially free from rosin acids and rosin substantially free from fatty acids are produced. With continued growth of the industry and further advances in tall oil technology, products of even greater refinement and wider utility may be expected in the not too distant future.     

Distillability of extracted mixed-birch tall oil

Chemical and physical properties of tall oil made in the CSR process and distillation results of three different types of distillation plants are presented. Chemically extracted, mixed-birch, tall oil differs remarkably from the normal Scandinavian crude tall oil. The extracted oil deviates from the normal, unextracted, mixed-birch tall oil with respect to the smaller unsaponifiable amount and the fatty acid esters. The amount of resin acid is small in extracted mixed-birch tall oil. The quantity of fatty acids, especially that of saturated fatty acids, is large. Distillation of extracted mixed-birch tall oil is most successful in a distillation plant where thin film evaporators are used.     

交联催化油浆/减压渣油改质制道路沥青

利用交联催化油浆和减压渣油为原料,将交联催化油浆减压蒸馏后得到的蒸馏残油与减压渣油进行调合,加入少量增延剂和PI改进剂制备70B道路沥青,为催化油浆综合利用探索了一条新途径。     

Recovery of sterols as fatty acid steryl esters from waste material after purification of tocopherols

Tocopherols are purified industrially from soybean oil deodorizer distillate by a process comprising distillation and ethanol fractionation. The waste material after ethanol fractionation (TC waste) contains 75% sterols, but a purification process has not yet been developed. We thus attempted to purify sterols by a process including a lipase-catalyzed reaction. Candida rugosa lipase efficiently esterified sterols in TC waste with oleic acid (OA). After studying several factors affecting esterification, the reaction conditions were determined as follows: ratio of TC waste/OA, 1∶2 (wt/wt); water content, 30%; amount of lipase, 120 U/g-reaction mixture; temperature, 40°C. Under these conditions, the degree of esterification reached 82.7% after 24 h. FA steryl esters (steryl esters) in the oil layer were purified successfully by short-path distillation (purity, 94.9%; recovery, 73.1%). When sterols in TC waste were esterified with FFA originating from olive, soybean, rapeseed, safflower, sunflower, and linseed oils, the FA compositions of the steryl esters differed somewhat from those of the original oils: The content of saturated FA was lower and that of unsaturated FA was higher. The m.p. of the steryl esters synthesized (21.7–36.5°C) were remarkably low compared with those of the steryl esters purified from high-b.p. soybean oil deodorizer distillate substances (56.5°C; JAOCS 80, 341–346, 2003). The low-m.p. steryl esters were soluble in rapeseed oil even at a final concentration of 10%.     

Production methods for the manufacture of crude tall oil and its subsequent processing

Summary The source of crude tall oil and methods to produce the oil have been described. These include acidulation of sulfate pulp, black liquor skimmings, and gravity settling as well as centrifugal means of separation to reduce the lignin content of the product. Subsequent processing of the crude tall oil into fractionated fatty acids and rosin has been outlined with suggestions for consideration in all stages of the distillation section of the plant.     

Spectrophotometric analysis of tall oil rosin acids

Summary About half of the rosin acids in whole and distilled tall oil consist of abietic and neoabietic acids, as distinguished from hydroabietic acids, dehydroabietic acid, and the pimaric acids. In this respect the tall oil rosin acids are similar to those from gum or wood rosin. This was established by spectrophotometric analysis of the rosin acids from whole tall oil, double distilled tall oil, rosin acids crystallized from tall oil, and rosin acids separated from tall oil by fractional distillation. The rosin acids crystallized from tall oil contained the highest percentage of abietic acid, but the sum of abietic and neoabietic acids was only slightly higher. The rosin acids from acid refined tall oil contained appreciably less abietic and neoabietic acid than the others. Before spectrophotometric analysis the rosin acids were isolated from the tall oils in about 95% yield by cyclohexylamine precipitation.     

Extraction of tocopherols from the deodorized distillate of soybean oil with liquefied petroleum gas

Deodorizer distillate, produced during the last processing step of edible oil refinement, is a mixture of tocopherols, sterols, fatty acids, glycerides, hydrocarbons, water and other materials. The amount of tocopherols in deodorizer distillate is large enough to be considered as raw material for vitamin E preparation. In this work, separation of tocopherols from sterols has been achieved using liquefied petroleum gas (LPG) extraction. LPG was chosen as extraction solvent in order to improve extract recovery and prevent tocopherol degradation.     

环氧大豆油新工艺的研究

研究了采用无溶剂合成环氧大豆油的新工艺。以大豆油、冰醋酸与双氧水为原料经催化、碱洗、水洗、减压蒸馏后制得环氧值≥6.0%的高质量产品，同时通过L9(3^4)正交试验对反应的工艺条件，原料配比与影响产品质量的各种因素进行了研究，确定最佳工艺条件是大豆油：双氧水：冰醋：浓硫酸之比是1：0.33：0.23：0.02。     

硬脂酸生产新工艺试验报告

硬脂酸旧的生产方法,手续繁琐,须经过多次压榨,否则成品中不饱和脂肪酸含量较多,质量就次。本研究系采用豆油或棉子油与桕油分别或混合进行极度氢化后水解,蒸馏即获得质量高的硬脂酸。以含水0.1％以下酸价0.5以下的精炼棉子油与桕油,用0.2—0.25％的镍催化剂,在表压5—10公斤,温度180—200℃情况下,在有良好搅拌的氢化罐内进行氢化,3小时以内即可达到极度氢化。继续裂解,6小时分解率可达到97％左右。成品的碘值在1以下。其中所含十八烷酸与十六烷酸的比例为45∶55或50∶50。因此完全适合化粧品工业所要求的规格。同时也避免了使用国内比较缺乏的牛羊油作为原料。     

The behavior of resin acids during tall oil distillation

The behavior of resin acids during tall oil distillation was studied by analyzing samples from six industrial-scale processes. The same artifact resin acids were formed in all processes. However, the proportion of artifact resin acids in tall oil rosins varied from 8.3 to 18.3% of the resin acids. The lowest values were found for two processes utilizing thin-film evaporators. The yield of resin acids in the tall oil rosin fraction varied from 62 to 80% of the resin acids in the crude tall oil feeds. Dehydroabietic acid was formed in all processes, the amount in rosin being 14-44% more than in the crude tall oil feed. Of the abietic acid, only 45-82% was recovered in the tall oil rosin fraction. The distribution of various resin acids and their reaction products during distillation was determined. Major resin acid impurities in tall oil fatty acids were 8,15-pimaradien-18-oic acid and 8,15-isoprimaradien-18-oic acid, both formed chiefly during distillation, and two secodehydroabietic acid isomers common in crude tall oils. The reactions of resin acids leading to new isomers or non-acidic products are discussed. Some results of this work were presented at the 173rd American Chemical Society Meeting, New Orleans, March 1977.     

Very long chain fatty acid methyl esters in transesterified palm oil

Some unidentified minor compounds have been observed in the residue from short-path distillation of transesterified palm oil that are not detected in the original palm oil. A method combining short-path distillation to enrich the unknowns with fractionation using solid-phase extraction is described. The fractionated components were identified using GC coupled with MS. The transesterified palm oil was found to contain methyl esters of up to C₃₂ carbon atoms. In the very long chain FAME with carbon numbers ≥20, both even and odd carbon numbers accounted for 0.26 wt%, with C₂₄ and C₂₆ being the major ones present in the residue after short-path distillation of transesterified palm oil.     

干馏渣替代煤矸石在预分解窑上的应用

油页岩低温干馏制取页岩油,其干馏产生的干馏渣和硅铝质原料(煤矸石)的化学成分相近并含有一定发热量。基于此,某新型干法生产线利用干馏渣替代部分硅铝质原料(烧煤矸石、黏土)用于水泥生料配料生产水泥熟料,介绍了其生产操作调整措施。实践证明,干馏渣替代部分硅铝质原料生产水泥是切实可行的,不仅能改善生料易烧性且价格低廉,降低了熟料煤耗和生产成本,具有广阔的市场应用前景。     

妥尔油酸二乙醇酰胺的合成及其润滑防锈性能研究

以妥尔油酸和二乙醇胺为原料合成了妥尔油酸二乙醇酰胺防锈剂,探讨了原料量配比、反应温度、反应时间等对产品性质的影响。合成产品的最佳条件是：原料配比为1∶3,在隔绝空气的条件下,升温至160℃左右,反应时间5h。在此条件下合成产品,并配制溶液对其防锈性能及表面活性进行测定,实验结果表明,此产品具有良好的防锈性能,可作为金属加工液的添加剂材料。     

劣质渣油调配90~#高等级道路沥青的研究

大庆原油经过常减压蒸馏得到劣质渣油,测定劣质渣油的性质,将劣质渣油和标准的70#高等级道路沥青1∶1比例初步调配。然后选择合适的再生剂C,添加8%的再生剂C,成功地调配出符合高等级道路90#石油沥青质量标准(GB50092.96)的合格沥青,从而使劣质渣油有效利用。     

Microbial conversion of sterol‐containing soybean oil production waste

Soybean extract residue (scum), a waste of soybean oil production, was examined as a raw material for C₁₇‐ketosteroid production. As a model process, its bioconversion to 9α‐hydroxyandrost‐4‐ene‐3,17‐dione (9‐OH‐AD) by Mycobacterium sp VKM Ac‐1817D was studied. The content of transformable sterols (sitosterol, stigmasterol and campesterol) in scum was estimated at ～14%. The bioconversion of scum to 9‐OH‐AD was characterized by a long lag‐period (300–350 h) followed by 9‐OH‐AD accumulation. The microbial or chemical elimination of fatty non‐identified components resulted in sterol‐enriched scum preparations. Effective conversion of these preparations by Mycobacterium sp was demonstrated: 9‐OH‐AD molar yield ～65% was reached at 60 h from the scum preparation containing 10 g dm^?3 transformable sterols. The process productivity was comparable with that for high quality‐sitosterol of wood origin (tall‐oil sitosterol). Copyright © 2004 Society of Chemical Industry     

Solvent extraction of fatty acids from natural oils with liquid water at elevated temperatures and pressures

The use of liquid water at elevated temperatures and pressures as an extractive solvent for separating mixtures of compounds which occur in natural oils has been studied. A southern pine tall oil and a distillate from the deodorization of soybean oil were extracted with liquid water at temperatures from 298 to 312°C and pressures between 103 and 121 bar. Results indicate that water can be used to extract fatty and resin acids from crude tall oil to obtain a product with a high acid content that produces less pitch during distillation. The process can also be used to extract fatty acids from vegetable oil deodorizer distillate.     

Pharmaceutical-grade sterols from tall oil

Summary A process has been developed for producing pharmaceutically-pure sterols from tall oil pitch. The process consists of the propane fractionation of the pitch, saponification of the overhead fraction in methanol, fractional crystallization, centrifuging, washing, and drying. A plant to produce 1,000 lbs. of sterols per day was brought into operation. This paper won first place in the 1958–59 Tall Oil Award of the Tall Oil Division of the Pulp Chemicals Association.     

冬青油合成工艺改进

在冬青油的合成过程中，采用精馏脱水酯化工艺。提高了一次酯化反应收率６％，总收率达到９５％以上。原料消耗也有所下降，反应时间缩短了三分之一。     

Purification of steryl esters from soybean oil deodorizer distillate

Soybean oil deodorizer distillate (SODD) contains steryl esters in addition to tocopherols and sterols. Tocopherols and sterols have been industrially purified from SODD but no purification process for steryl esters has been developed. SODD was efficiently separated to low b.p. substances (including tocopherols and sterols) and high b.p. substances (including 11.2 wt% DAG, 32.1 wt% TAG, and 45.4 wt% steryl esters) by molecular distillation. The high b.p. fraction is referred to as soybean oil deodorizer distillate steryl ester concentrate (SODDSEC). We attempted to purify steryl esters after a lipase-catalyzed hydrolysis of acylglycerols in SODDSEC. Screening of industrially available lipases indicated that Candida rugosa lipase was most effective. Based on the study of several factors affecting hydrolysis, the reaction conditions were determined as follows: ratio of SODDSEC/water, 1∶1 (w/w); lipase amount, 15 U/g reaction mixture; temperature, 30°C. When SODDSEC was agitated for 24 h under these conditions, acylglycerols were almost completely hydrolyzed and the content of steryl esters did not change. However, study with a mixture of steryl oleate/trilinolein (1∶1, w/w) indicated that about 20% of constituent FA in steryl esters were exchanged with constituent FA in acylglycerols. Steryl esters in the oil layer obtained by the SODDSEC treatment with lipase were successfully purified by molecular distillation (purity, 97.3%; recovery, 87.7%).