Oil Deodorizer Distillate Research Articles

Irresolvable complex mixture of hydrocarbons in soybean oil deodorizer distillate

Aliphatic hydrocarbons (HCs) can be used as a fingerprint of a given seed oil. Only by characterization of aliphatic HCs could contamination by mineral oil in that seed oil be confirmed. During the isolation of squalene from soybean oil deodorizer distillate, a significant amount of unknown HCs, ca. 44 wt%, was obtained. These seemingly-easy-to-identify HCs turned out to be much more difficult to elucidate due to the presence of an irresolvable complex mixture (ICM). The objective of this study was to purify and identify the unknown ICM of aliphatic HCs from soybean oil deodorizer distillate. Purification of the ICM was successfully achieved by using modified Soxhlet extraction, followed by modified preparative column chromatography, and finally by classical preparative column chromatography. FT-IR, TLC, elemental analysis, GC/FID, NMR and GC-MS analyses were then performed on the purified HCs. The GC chromatogram detected the presence of ICM peaks comprising two major peaks and a number of minor peaks. Validation methods such as IR and NMR justified that the unknowns are saturated HCs. This work succeeded in tentatively identifying the two major peaks in the ICM as cycloalkane derivatives.

Separation of squalene from olive oil deodorizer distillate using supercritical fluids

AbstractIn this study, an integrated strategy using supercritical fluids for extraction of squalene from olive oil deodorizer distillate (OODD), one of the most important by‐products of the olive oil refining process is presented. First, OODD was esterified in supercritical methanol, and then squalene was extracted from the sample consisting of 66% methyl ester using supercritical CO2. The extraction conditions, i.e., pressure (88.2–121.8 bar), temperature (41.6–58.4°C) and extraction time (129.6–230.4 min), were optimized via RSM to achieve the highest squalene content. The optimal results were obtained at a temperature of 52.05°C, pressure of 104.8 bar and extraction time of 180 min. Consequently, two kinds of value‐added products such as biodiesel (up to 96% FAME, in extract) and olive squalene (up to 75%, in raffinate) were produced in shorter processing times when compared with distillation results of 70 h.Practical applications: Traditionally, squalene is extracted from liver oil of rare deep‐sea sharks. Here we present the recovery of vegetal squalene in high purity from OODD. Our approach also presents a simple, reliable, and mobile solution. Squalene is widely used in cosmetics as a protective agent and natural moisturizer and as an adjuvant in influenza vaccines.

Synthesis of Biodiesel from by-Product of Plant Oil by the Catalysis of Solid Acid in Fixed Bed

Fatty acid methyl ester biodiesel was successfully synthesized by the esterification of the palm oil deodorizer distillate (PODD) with methanol, catalyzed by the strongly acidic cation-exchange resin as solid acid in a self-made fixed bed reactor. The reaction condition was optimized, and the product could basically reach both national standard and Germany standard.

Liquid−Liquid Phase Transition of Mixtures Comprising Squalene, Olive Oil, and Ethyl Lactate: Application to Recover Squalene from Oil Deodorizer Distillates

Experimental and modeling studies of the liquid−liquid equilibria at ambient pressure of three model systems—squalene + ethyl lactate, olive oil + ethyl lactate, and squalene + olive oil + ethyl lactate—were performed with the view to explore the potential application of an agrochemical solvent, namely, ethyl lactate, to recover squalene from pretreated olive oil deodorizer distillate. The favorable separation factors obtained reveal the strength and potential of ethyl lactate as a green solvent for the recovery of squalene from squalene + triglyceride mixtures.

A Simple Two-Step Method for Simultaneous Isolation of Tocopherols and Free Phytosterols from Soybean Oil Deodorizer Distillate with High Purity and Recovery

Most of the methods reported for isolating phytosterols and tocopherols from soybean oil deodorization distillate (SODD) involved complicated steps or failed to obtain high content and recovery. In this study, we succeeded in isolating α-, δ-, γ-tocopherols, and free phytosterols (campesterol, stigmasterol, and β-sitosterol) from SODD with high content and recovery. Our protocol involved a simple two-step method. SODD was separated into non-polar and polar fraction by modified soxhlet extraction. Cold saponification was chosen instead of conventional saponification which is carried out at a temperature no lower than 60°C. This study of cold saponification was applied to the polar fraction to remove free fatty acids and acylglycerols. SODD contains 9.13 ± 0.28% tocopherols and 9.75 ± 0.12% free phytosterols, was converted to a final product which contains 38.08 ± 0.36% tocopherols and 55.51 ± 0.56% free phytosterols. The total recovery of tocopherols and free phytosterols is 94 ± 0.19%.

Isolation of sterols from sunflower oil deodorizer distillate

A new method for isolating sterols from sunflower oil deodorizer distillate (DOD) was developed. The most salient feature of which is that, unlike most alternatives, it requires no distillation. Briefly, the method uses methanol in the presence of p-toluenesulphonic acid as catalyst to convert free fatty acids and acyl glycerides in DOD into fatty acid methyl esters (FAMEs). The resulting glycerin and excess reagents are removed by washing with water and, finally, the product is cooled in the absence of solvents to obtain sterols in 92 ± 2% purity.

Cogeneration of biodiesel and tocopherols by combining pretreatment with supercritical carbon dioxide extraction from soybean oil deodorizer distillate

Cogeneration of biodiesel and tocopherols from soybean oil deodorizer distillate (SODD) combining pretreatment with supercritical carbon dioxide (SC-CO2) extraction was investigated. The pretreatment procedures included esterification by cation exchange resin catalyst, cold recrystllization to removing sterols, and then transesterification by alkali. After pretreatment, the conversion ratio of free fatty acid (FFA) and triglycerides (TGs) of SODD to methyl esters (biodiesel) was over 96% and retention of tocopherols was over 94%. Further, the pretreated SODD was extracted by SC-CO2 to obtain biodiesel and tocopherols simultaneously. It was demonstrated that combining pretreatment with SC-CO2 is a promising technology for cogeneration production of biodiesel and tocopherols from SODD.

Analysis of trans–cis fatty acids in fatty acid steryl esters isolated from soybean oil deodoriser distillate

The characterisation of the isolated natural product from soybean oil deodoriser distillate (SODD) has gained increasing importance due to health concerns. The purpose of the present work was to characterise fatty acids steryl esters (FASEs) composition and to determine the trans fatty acids (TFAs) contents in FASEs obtained from SODD by using simple and accurate method. Isolation of FASEs with saturated fatty acids moieties from FASEs mixture was also developed. It was found that the fatty acids composition of the isolated FASEs were 31.74% palmitate acid (C16:0), 9.99% stearic acid (C18:0), 0.46% elaidic acid (C18:1 trans-9), 27.51% oleic acid (C18:1 cis-9), 0.19% linoleaidic acid (C18:2 cis-9, trans-12), and 29.19% linoleic acid (C18:2 cis-9, cis-12). TFAs, which account for about 0.65% of the total fatty acids, were detected in the isolated FASEs. Palmitate and stearate steryl esters isolated from SODD are promising natural product because they are free of trans-isomers.

Physicochemical Characteristics and Composition of Indian Soybean Oil Deodorizer Distillate and the Recovery of Phytosterols

AbstractThe deodoriser distillate (DOD) of Indian soybean oil obtained from two industries processing soybean oil was investigated for its physicochemical characteristics, its composition of tocopherols, phytosterols, fatty acids and recovery of phytosterols for use in nutraceutical products. It was found that the two DOD samples studied were dark in color and had higher amounts of free fatty acids (22.7 and 49.9%), unsaponifiable matter (11.8 and 21.9%) (5–10 times found in soybean oil), total tocopherols (1957–2256 mg/100 g) (20 times the amount in soybean oil), and 6–10% of phytosterols (12–20 times the soybean oil). The fatty acids found were palmitic (23.2–25.5%), stearic (1.4–2.4%), oleic (23.8–26.1%), linoleic (40.4–41.1%) and linolenic (2.7–3.2%) acids. The unsaponifiable matter (21.9%) and phytosterols (8.7%) content of DOD‐2 were higher than in DOD‐1 and hence was more suited for isolation of phytosterols. Using hexane and water for crystallisation, the DOD‐2 yielded a phytosterol fraction with lower recovery of 13.2–17.8% while treatment with alkali to remove FFA and the glycerides followed by organic solvent extraction yielded unsaponifiable matter containing phytosterols with a recovery of 74.6%. Later the unsaponifiable matter was purified by double crystallisation into a mixture of phytosterols of 87% purity containing β‐sitosterol (34.3%), stigmasterol (3.1%) and campesterol (50.1%). The product may find use in foods, pharmaceuticals, cosmetics and allied industries probably as a nutraceutical.

Production of natural antioxidants from vegetable oil deodorizer distillates: Effect of catalytic hydrogenation

Natural tocopherols are one of the main types of antioxidants found in living creatures, but they also have other critical biological functions. The biopotency of natural (+)-α-tocopherol (RRR) is 36% higher than that of the synthetic racemic mixture and 300% higher than the SRR stereoisomer. Vegetable oil deodorizer distillates (DD) are an excellent source of natural tocopherols. Catalytic hydrogenation of DD preconcentrates has been suggested as a feasible route for recovery of tocopherols in high yield. However, it is important to know whether the hydrogenation operation, as applied to these tocopherol-rich mixtures, is capable of preserving the chiral (RRR) character, which is critical to its biopotency. Fortified (i.e., (+)-α-tocopherol enriched) sunflower oil and methyl stearate, as well as sunflower oil DD, were fully hydrogenated using commercial Ni and Pd catalysts (120–180 °C; 20–60 psig). Products were analyzed by chiral HPLC. Results show that the desired chiral configuration (RRR) is fully retained. Thus, the hydrogenation route can be safely considered as a valid alternative for increasing the efficiency of tocopherol recovery processes from DDs while preserving their natural characteristics.

Recovery of phytosterols from waste residue of soybean oil deodorizer distillate

This study describes a catalytic decomposition and crystallization process to recover phytosterols from the waste residue of soybean oil deodorizer distillate (WRSODD). Various solvents were used for the crystallization of phytosterols. The effect of different solvents on the purity and yield of recovered phytosterols was investigated. The composition of WRSODD was analyzed by silica gel column chromatography and FT-IR spectrum. Gas chromatography (GC), GC–MS, and FT-IR were adopted to determine the purity and structure of phytosterols. Results showed the total amount of phytosterols, in the form of fatty acid steryl esters, was up to 20 wt.% of WRSODD. Through orthogonal experiments, the optimized crystallization conditions were obtained. It’s found the mixed solvent of acetone and ethanol (4/1, v/v) could generate good crystallization. The yield of recovered phytosterols was 22.95 wt.% after the 1st crystallization. The purity of phytosterols reached 91.82, 92.73, and 97.17 wt.% after the 1st, 2nd, and 3rd crystallization, respectively.

Vegetable Oil Deodorizer Distillate: Characterization, Utilization and Analysis

Depending on the sources, deodorizer distillates usually have significantly different characteristics, uses, and value. Soybean oil deodorizer distillate has been suggested as an alternative to marine animals as natural source of squalene and as a good raw material for the production of fatty acid steryl esters, tocopherols, free phytosterols and fatty acids. The aim of this review paper is to discuss the characteristics, uses, and value of vegetable oil deodorizer distillate (VODD), isolation and separation techniques of bioactive compounds from VODD, and analysis of VODD, as well as their future perspectives. The development of new separation techniques for isolating bioactive compounds and methods of analysis are highlighted and discussed.

Optimisation of enzymatic pretreatment of soybean oil deodoriser distillate for concentration of tocopherols

SummaryTocopherols have been purified from the deodoriser distillate produced in the final deodorisation step of vegetable oil refining by a process including molecular distillation. The deodoriser distillate contains mainly tocopherols, sterols and free fatty acids (FFAs); the presence of FFAs hinders tocopherol purification. In general, Candida rugosa lipase recognised FFAs as substrates but not tocopherols, and esterification of FFAs with methanol (MeOH) could be processed in an organic solvent‐free system. Several factors affecting esterification of FFAs were investigated in detail and optimised by the Plackett–Burman and the central composite design. The optimal reaction conditions are as follows: water content 21.05%, lipase 115.45 U g−1 mixture, temperature 28.95 °C and addition of methanol and FFA in a molar ratio of 4:1 in four steps, with degree of decrease of acid value (AV) above 93% in 18 h; this was a much efficient process. No significant tocopherol losses were observed during the process. In conclusion, enzymatic esterification of FFAs in soybean oil deodoriser distillate for concentration of tocopherols was shown to be a technically viable process.

Biodiesel synthesis combining pre-esterification with alkali catalyzed process from rapeseed oil deodorizer distillate

A two-step technique combining pre-esterification catalyzed by cation exchange resin with transesterification catalyzed by base alkali was developed to produce biodiesel from rapeseed oil deodorizer distillate (RDOD). The free fatty acids (FFAs) in the feedstock were converted to methyl esters in the pre-esterification step using a column reactor packed with cation exchange resin. The acid value of oil was reduced from the initial 97.60 mg-KOH g − 1 oil to 1.12 mg-KOH g − 1 oil under the conditions of cation exchange resin D002 catalyst packed dosage 18 wt.% (based on oil weight), oil to methanol molar ratio 1:9, reaction temperature 60 °C, and reaction time 4 h. The biodiesel yield by transesterification was 97.4% in 1.5 h using 0.8 wt.% KOH as catalyst and a molar ratio of oil to methanol 1:4 at 60 °C. The properties of RDOD biodiesel production in a packed column reactor followed by KOH catalyzed transesterification were measured up the standards of EN14214 and ASTM6751-03.

Separation of Nonpolar Lipid from Soybean Oil Deodorizer Distillate by Stirred Batch-Wise Silica Gel Adsorption-Desorption

In this study, the stirred batch-wise adsorption-desorption was employed to separate soybean oil deodorizer distillate (SODD) into a nonpolar lipid fraction (NPLF) and a polar lipid fraction (PLF). Starting with SODD that contains 4.35% fatty acid steryl esters (FASEs), 1.92% squalene, 13.19% tocopherols, and 9.22% free phytosterols, it was possible to obtain NPLF enriched with FASEs (19.5%, recovery 96.93%) and squalene (9.15%, recovery 100%). The contents of FFAs, TAGs, tocopherols, and free phytosterols remained in the NPLF were 11.59%, 1.36%, 4.83%, and 1.45%, respectively. The batch extraction employed in this study yielded about the same degree of separation as compared to that of modified soxhlet extraction. However, the advantage of the method of this study is that it can be scaled-up easily.

Biodiesel production from rapeseed deodorizer distillate in a packed column reactor

In this study, a technical method investigating biodiesel production in a column reactor packed with cation exchange resin from rapeseed oil deodorizer distillate (RODD) was addressed. The results showed that D002 cation exchange resin presented more efficiently catalytic activity than 002CR and 732 resins in a packed column reactor. Biodiesel yield achieved over 96% under the optimal conditions: D002 resin catalyst dosage 18 wt.% (based on oil weight), oil to methanol molar ratio 1:9, reaction temperature 60 °C, and reaction time 4 h. When the packed resin catalyst was recovered, biodiesel yield was over 88% after 10 repeated batch cycles (40 h). The comparison of biodiesel production in a packed column reactor and catalyzed by traditional sulfuric acid from RODD was also studied. It was concluded that biodiesel synthesis in a packed column reactor would be a potential way for biodiesel production from RODD.

Isolation and identification of steroidal hydrocarbons in soybean oil deodorizer distillate

Abstract In the isolation of squalene from soybean oil deodorizer distillate (SODD), ca. 30% of nonpolar lipid fraction (NPLF) is hydrocarbons (HCs), which can be divided into three main groups, namely aliphatic HCs, steroidal HCs and terpene HCs. The steroidal HCs content of vegetable oil can be used as a means of identifying the oil and therefore, for detecting adulteration. The objective of this study was to isolate the steroidal HCs contained in SODD and identify the individual steroidal HCs. Isolation of steroidal HCs can be achieved in three steps: modified Soxhlet extraction, modified silica gel column chromatography, and distillation. Identification of individual steroidal HCs was accomplished by TLC, GC and GC–MS analyses. The GC chromatogram of steroidal HCs showed five major peaks. Most of the major peaks were identified as derivatives of free sterols. Special attention was needed in order to identify isomers which differ in the position of double bonds and compounds which have three double bonds in the ring system.

Simulation and optimization of supercritical fluid purification of phytosterol esters

Supercritical carbon dioxide extraction to separate phytosterol esters from fatty acid esters and tocopherols was simulated and optimized using the group contribution equation of state. Experimental extraction data at 328 K, pressures ranging from 200 to 280 bar and solvent-to-feed ratio around 25, was employed to verify the performance of the thermodynamic model. The raw material is the product obtained after a two-step enzymatic reaction carried out on soybean oil deodorizer distillates, and contains mainly fatty-acid ethyl esters, tocopherols and phytosterol esters. The extraction process was simulated using model substances to represent the complex multicomponent feed material. Nonlinear programming techniques were applied to find out optimal process conditions for a steady-state countercurrent process with partial reflux of the extract. The process optimization procedure predicts that a product with 94.2 wt % of phytosterol ester purity and 80% yield could be achieved. © 2009 American Institute of Chemical Engineers AIChE J, 2009

Biodiesel Synthesis via Esterification of Feedstock with High Content of Free Fatty Acids

The objective of this work was to study the synthesis of ethyl esters via esterification of soybean oil deodorizer distillate with ethanol, using solid acid catalysts and commercial immobilized lipases, in a solvent-free system. Three commercially immobilized lipases were used, namely, Lipozyme RM-IM, Lipozyme TL-IM, and Novozym 435, all from Novozymes. We aimed for optimum reaction parameters: temperature, enzyme concentration, initial amount of ethanol, and its feeding technique to the reactor (stepwise ethanolysis). Reaction was faster with Novozym 435. The highest conversion (83.5%) was obtained after 90 min using 3 wt.% of Novozym 435 and two-stage stepwise addition of ethanol at 50 degrees C. Four catalysts were also tested: zeolite CBV-780, SAPO-34, niobia, and niobic acid. The highest conversion (30%) was obtained at 100 degrees C, with 3 wt.% of CBV-780 after 2.5 h. The effects of zeolite CBV 780 concentration were studied, resulting in a conversion of 49% using 9 wt.% of catalyst.

Stepwise Esterification of Phytosterols with Conjugated Linoleic Acid Catalyzed by Candida rugosa Lipase in Solvent-free Medium

We conducted a near quantitative esterification of phytosterols from soybean oil deodorizer distillate with conjugated linoleic acid. We used a 1:1 molar ratio of sterols to conjugated linoleic acid. For that matter, stepwise addition of sterols was investigated. Total sterols were divided into several portions and added sequentially to the reaction mixture. Using this methodology, purities of up to 80% steryl esters were obtained that consumed more than 90% of the total conjugated linoleic acid. In addition, the effects of temperature, amount, and stability of lipase were also evaluated.