Vegetable Oil Deodorizer Distillate Research Articles

Lowering polycyclic aromatic hydrocarbon concentrations in vegetable oil deodorizer distillates and enhancing its utilization by graphene composites

Vegetable oil deodorizer distillates (VODDs), which are the main source of natural tocopherol, are easily contaminated by polycyclic aromatic hydrocarbons (PAHs), and pose health threats to human beings. To remove 16 priority-control PAHs in VODD, three graphene (GR) composites, including TiO2-GR, sepiolite-GR and Fe3O4-GR, were prepared. PAH concentrations and removal rates were determined using gas chromatography-mass spectrum (GC-MS). Additionally, density functional theory (DFT) calculation was conducted to simulate and illustrate PAH adsorption on GR composites. The results indicated that the highest BaP removal rate was given to TiO2-GR with 90.37 ± 3.23 % after 2 h in standard solution. The adsorption followed the pseudo-first order kinetic, with the constant of −0.0141. In contrast, 61.62 ± 7.88 % total PAHs were removed in VODD using TiO2-GR. Moreover, DFT calculation verified that the strongest adsorption effect occurred between TiO2-GR and PAHs, with the adsorption energy of −2.69 eV. Additionally, GR composite morphology would be changed when LPAH concentrations are higher than 30 μg kg-1. The results also indicated the retention rates tocopherol ranged from 91.91 ± 1.92 % to 99.22 ± 0.88 %. This study firstly provides a useful tool for PAH removal in VODDs while retaining tocopherol. Moreover, it will increase the understanding of adsorption process between PAHs and GR composites.

Application of pilot‐scale molecular distillation for enrichment of phytonutrients from a novel deodorizer distillate of the margarine and shortenings industry

AbstractBackgroundA wiped‐film molecular distillation (WFMD) pilot plant was used to evaluate process conditions for enriching phytonutrients (PN) from a novel vegetable oil deodorizer distillate (VODD) of the margarine and shortenings industry. This byproduct results from the incorporation of new blends of vegetable oils, such as soybean and palm oil, making it of interest due to its distinct chemical composition and matrix, which differ from those of deodorizer distillates studied previously. The significance of the present investigation is related to the properties of the oil blend, requiring the establishment of new process conditions for this specific VODD. Experimental design was used to evaluate the WFMD process variables, with the aim of removing free fatty acids and enabling eight PN to be concentrated in the reprocessing stages.ResultsThe product obtained after three WFMD stages presented a fivefold increase in the total PN concentration, compared to the raw material. Notably, the procedure provided enrichment ratios of 7.2‐fold for total tocopherols (including α‐, β‐, λ‐ and δ‐tocopherols), 4.5‐fold for total phytosterols (including campesterol, stigmasterol and β‐sitosterol) and 1.2‐fold for squalene, together with a deacidification efficiency of 78.93%.ConclusionThe proposed process provided significant concentration gains for all eight PN evaluated, resulting in a value‐added product. These excellent results were achieved using only three WFMD stages, without any need for additional processing steps. The data obtained at the pilot scale provide valuable insights for predicting the scalability of the process and facilitating potential industrial implementation. © 2023 Society of Chemical Industry.

Synthesis of Alpha Olefins: Catalytic Decarbonylation of Carboxylic Acids and Vegetable Oil Deodorizer Distillate (VODD)

Decarbonylation of carboxylic acids provides an effective protocol for producing alpha olefins; however, previous literature has focused on the palladium-bisphosphine catalysts and has only sporadically studied the palladium-monophosphine catalyst. To investigate the catalytic activity of the palladium-monophosphine catalyst on decarbonylation of carboxylic acids, new monophosphine ligands were synthesized (NP-1, NP-2, CP-1 and CP-2). By employing (1–3 mol%) palladium-naphthylphosphine catalysts, various carboxylic acids were converted into corresponding alpha alkenes with good yields and selectivity within a short period of time. Vegetable oil deodorizer distillate (VODD), which is a by-product from the vegetable oil refinery process, was found to be rich in free fatty acids and there is great interest in turning vegetable oil deodorizer distillate into value-added compounds. It is noteworthy that our catalytic system could be applied to convert vegetable oil deodorizer distillate (VODD) into diesel-like hydrocarbons in a good yield.

Glycerolysis of free fatty acid in vegetable oil deodorizer distillate catalyzed by phosphonium-based deep eutectic solvent

Abstract Esterification of free fatty acids in a low-grade oil with glycerol, the by-product of transesterification, has been proposed as one possible method to reduce the cost of raw materials for biodiesel production. The glycerolysis reaction recycles the byproduct glycerol to create a much more efficient and cost-effective process. However, the glycerolysis reaction involves challenges, including its requirement of high temperature. This study is the first to apply the deep eutectic solvent (DES) as a catalyst for glycerolysis reaction to convert free fatty acid (FFA) in vegetable oil deodorizer distillate (VODD) being a waste product from the oil refining process into glycerides. The effects of temperature, catalyst dosage, and time on the esterification efficiency of fatty acid conversion were explored. The reaction progress and product solubility were studied by FT-IR and GC. The results revealed that the reaction reached equilibrium at an approximate free fatty acid (FFA) conversion of 90%. The reaction was a second-order reversible reaction, using 8 wt% catalyst loading lowered activation energy to 58.80 J/mol. The optimum condition was determined as 160 °C, 5 wt% DES loading, and 10 min reaction time.

Analysis of PAHs in oily systems using modified QuEChERS with EMR-Lipid clean-up followed by GC-QqQ-MS

Polycyclic aromatic hydrocarbon (PAH) analysis in oily matrices is a great challenge that needs improvements both in efficiency and environmental sustainability. In this study, a method based on QuEChERS and gas chromatography-quadrupole tandem mass spectrometry (GC-QqQ-MS) was established. The method was based on EMR-Lipid as the dispersed solid phase adsorbent and acetonitrile: acetone (3:2, v/v) as the extraction solvent. The recovery of 16 PAHs reached 66.72–112.87%; the RSD was less than 8%, and the LOD and LOQ were lower than 0.13 μg/kg and 0.43 μg/kg, respectively. Compared to the ISO 15753 method, our method reduced the pretreatment time by 2/3 and improved the recovery of heavy PAHs, such as fluoranthene, benzo[a]anthracene and benzo[b]fluoranthene. The low solvent usage of 10 mL was also environmentally friendly for a high throughput basis. After verification, the method was successfully applied to determine the PAHs in 12 real oily samples, including waste frying oils (WFOs) and vegetable oil deodorizer distillates (VODDs). The PAH concentrations determined in the WFOs and VODDs ranged from 39.21 to 197.44 μg/kg and 1219.34–1482.25 μg/kg, respectively. Our work suggests that the proposed method can serve as an alternative approach for the efficient and precise determination of PAHs in edible oils and other oily systems as well as a potential analytical approach to evaluate PAHs in foods and drinks. Furthermore, the PAH data for the WFOs indicate that the PAH level should be introduced as a safety index for the obsoleting of frying oil.

Lipase catalyzed deacidification of tocopherol-rich distillates obtained from natural Vitamin E sources

Abstract Taking into account the great interest of consumers for high purity natural vitamin E preparations, it is highly desirable to develop an efficient process for recovering Vitamin E from vegetable oil deodorizer distillates (VODDs) with reduction in costs and better use of energy. The process described herein involves a series of treatment steps, namely desaromatization of VODD, concentration of tocopherols by molecular distillation at high vacuum, lipase catalyzed ester synthesis, and brightening of the resulting tocopherol-rich concentrate with an ethanol (96%):water 60:40 mixture which are similar to conventional processes but the purpose and order of execution of some of them are clearly different. Moreover, some treatment steps were shortened or directly removed. By this process a fully translucent and fluid product was obtained which had tocopherol richness near to the standardized level of 50% concentration, acidity around 1% and a content of emulsifying mono- and diglycerides of 20%. The mixture of mono- and diglycerides that result from the enzymatic process could facilitate absorption of tocopherols by the body and thereby enhancing the biological activity of these compounds. Because all these facts the process presented is feasible as a new industrial purification method of tocopherols from VODDs.

Separation of major and minor lipid components using supercritical CO2 coupled with cross-flow reverse osmosis membrane filtration

A reverse osmosis polyamide membrane was used to test the feasibility of concentrating triacylglycerol (TAG) and α-tocopherol/β-sitosterol from model mixtures (Oleic Acid (OA)/TAG and OA/α-tocopherol/β-sitosterol, respectively) solubilized in SC-CO2 using cross-flow filtration regime. SG membrane was used for up to 26 h at pressures of 120 and 280 bar and temperature of 40 °C and its performance was measured in terms of CO2 flux and separation factor at a transmembrane pressure of 10 bar. Increasing the pressure to 280 bar resulted in a higher reduction in CO2 flux in comparison to that at 120 bar, which was attributed to fouling. CO2 flux was reestablished after cleaning with pure SC-CO2. Feed pressure of 120 bar showed the best separation factors, where the OA separation factor was higher than 1 and those for TAG and α-tocopherol/β-sitosterol were less than 1. The preferential permeation of OA through the reverse osmosis membranes in comparison to TAG and α-tocopherol/β-sitosterol could be attributed to the higher diffusivity of this smaller molecular weight compound and the effect of plasticization and swelling of the membrane upon exposure to SC-CO2. The cross-flow regime efficiently reduced the extent of fouling and subsequent decline of permeate flux. The findings demonstrate the potential to separate bioactive components present in vegetable oil deodorizer distillate and/or to deacidify vegetable oils using coupled supercritical and membrane technologies.

Vegetable Oil Deodorizer Distillate: A Rich Source of the Natural Bioactive Components.

Deodorizer distillates are waste products of edible oil processing industries obtained during deodorization process of vegetable oils. It is very cheap source of several health beneficial components such as tocopherols, sterols, squalene as well as free fatty acids which have numerous industrial applications. These valuable components are being used in different foods, pharmaceutical formulations and cosmetics. Traditional sources of these useful components are vegetable oils, fruits, vegetables and nuts. Global need of these important components has been exceeded than their availability. The deodorizer distillates of various vegetable oils are considered to be a rich source of several valuable components. Present review will cover brief introduction of common processing stages involved in all vegetable oil processing, analytical methods for characterization of deodorizer distillates by instrumental techniques, importance and commercial value of deodorizer distillates. Future prospective of current field may leads to cost efficient processes and increased attention on the nutritional quality of deodorized oil and commercial applications of deodorizer distillates as well as their valuable components.

Composition of Plant Sterols and Stanols in Supplemented Food Products.

All fruits, vegetables, grains and other plant materials contain small amounts of plant sterols, which are essential for the function of the biological membranes in living cells. The average human consumption of plant sterols has been estimated to be about 150-350 mg/day and trace amounts of stanols (which are defined as saturated sterols such as sitostanol), but this number varies regionally and is higher for vegetarians. When consumed in the diet, plant sterols reduce the levels of serum cholesterol. In 1995 the first functional food product, Benecol spread (enriched in plant stanol fatty acid esters), was developed by Raisio and marketed, first in Finland and then globally. Since then many other functional food products have been developed and are now available globally. In addition to stanol esters, other functional food products contain plant sterol esters and/or free (unesterified) plant sterols and stanols. In essentially all of the current functional foods that are enriched in sterols and stanols, the feedstock from which the sterols and stanols are obtained is either tall oil (a byproduct/coproduct of the pulping of pine wood) or vegetable oil deodorizer distillate (a byproduct/coproduct of the refining of vegetable oils).

Simultaneous HPLC–DAD Analysis of Tocopherols, Phytosterols, and Squalene in Vegetable Oil Deodorizer Distillates

A simple and accurate HPLC–DAD method has been developed for simultaneous determination of tocopherols (α, (β + γ), and δ-tocopherols), phytosterols (campesterol, β-sitosterol, and stigmasterol), and squalene in vegetable oil deodorizer distillates (VODD). Chromatographic separation was performed on a C18 column with a mobile phase gradient prepared from 98:2 (v/v) methanol–water and isopropanol, at a flow rate of 1.0 mL min−1, in 33 min, at 30 °C. Tocopherols, phytosterols, and squalene were detected at 296, 210, and 210 nm, respectively. Recoveries ranged from 92.4 to 103.8 %. Limits of quantification were in the range 0.50–2.50 μg mL−1. The proposed method was successfully used for simultaneous analysis of tocopherols, phytosterols, and squalene in VODD.

Lipase-Catalyzed Consecutive Batch Reaction for Production of Steryl Esters from Vegetable Oil Deodorizer Distillates

A significant decrease of the yield of steryl esters production via the esterification of sterols and free fatty acids (FFA) present in vegetable oil deodorizer distillates was observed when consecutive batch reactions (24 hr each) were carried out using the same enzyme and under optimal operating conditions. The objective of this work is to identify the causes of such phenomena, in order to avoid or minimize it, allowing for reuse of the Candida rugosa lipase catalyst in consecutive batch reactions. The effect of water activity and glycerol produced by hydrolysis of acylglycerides, on the stability of the enzyme was studied. Results show that these effects were not the main reason for the decrease of yield in consecutive batch reactions. The presence of oxidation products proved to play an important role in the enzyme inactivation. Because of the high concentration of antioxidants (phenolic compounds, squalene, and tocopherols) naturally present in deodorizer distillates, the inactivation of the enzyme was minimized; nevertheless, it could not be avoided. A partial reuse of the enzyme is technically a possible solution, by adding fresh enzyme in the beginning of each batch reaction. Four consecutive batch reactions (24 hr each) were successfully carried out under optimal conditions, keeping a constant yield of steryl esters (SE) production (>85%).

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.

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.

Free fatty acid separation from vegetable oil deodorizer distillate using molecular distillation process

Distillates of the vegetable oil deodorization are composed of free fatty acids (FFA), sterols, tocopherols, sterol esters, hydrocarbons and breakdown products of fatty acids, aldehydes, ketones and acylglycerols. The content of free fatty acids in deodorizer distillates varies between 25 and 75%. Due to its high content, free fatty acid separation from deodorizer distillate is an important step to concentrate tocopherols to high purity. Tocopherols are valuable natural substances used in food, cosmetic and pharmaceutical industries. In this work, separation of free fatty acids from soybean oil deodorizer distillate (SODD) was investigated through molecular distillation, using different operating conditions. Evaporator temperature from 100 to 180 °C and feed flow rate in the range of 1.5–23.0 g min −1 were used in the experiments. FFA and tocopherols contents were monitored in each stream generated by the molecular distillation process (distillate and residue streams). The intention is to determine the best operating conditions to produce a material with minimum FFA content and to minimize tocopherol losses during the process. Removal of FFA in the distillate stream resulted in a preliminary concentration of tocopherols, which is removed in the residue stream of the molecular distillation. The results showed that an efficient FFA separation from SODD with the lowest loss of tocopherols requires specific operating conditions. It was possible to obtain a material with 6.4% of FFA and 18.3% of tocopherols from a raw material composed by 57.8% of FFA and 8.97% of tocopherols, using 160 °C of evaporator temperature and 10.4 g min −1 of feed flow rate. These results represent FFA elimination of 96.16% and tocopherol recovery of 81.23%.

Phytosterol-enriched triglyceride fractions from vegetable oil deodorizer distillates utilizing supercritical fluid fractionation technology

Supercritical fluid fractionation (SFF) technology has been applied as an alternative method to recover phytosterol (St)-enriched triglyceride (TG) fractions from vegetable oil deodorizer distillates (DD). Utilizing a pilot scale high pressure packed column, it was possible to obtain oil fractions with 20 and 31% St, 38 and 30% TG, from rice bran and soybean oil DD, respectively. A two step SFF method was developed further to obtain low free fatty acid and high TG and St content oil fractions from rice bran and soybean oil DD.

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.