An international robin round was carried out to validate a method for the quantification of 2-monochloropropane-1,3-diol (2-MCPD), 3-monochloropropane-1,2-diol (3-MCPD) and 2,3-epoxy-1-propanol (Glycidol) being present as fatty acid esters in plant-based food emulsifiers. The evaluated method was a modification of the American Oil Chemist´s Society (AOCS) Official Method Cd29b-13. Briefly, this method consists from parallel analysis of two sample aliquots that are spiked with different sets of internal standards. Mild alkaline interesterification overnight in the freezer releases the core analytes. Reaction stop and glycidol conversion into monobromopropanediol (MBPD) is realised by addition of acidified sodium bromide solution. Subsequently, matrix removal and analyte extraction are achieved by two liquid/liquid (l/l) extraction steps. After derivatisation with phenylboronic acid (PBA) the final extracts are analysed by gas chromatography-mass spectrometry (GC-MS). Quantification is carried out by internal one-point-calibration. 6 laboratories from 4 European countries participated in the trial and reported 8 data sets for 10 test materials (mono- and diacylglycerides as well as polyglycerol polyricinoleates) that were analysed as blind duplicates, giving a total of 20 samples. Result outliers were eliminated according to accepted standards. At 2-MCPD levels above 0.02 mg/kg, 3-MCPD levels above 0.06 mg/kg and glycidol levels above 0.22 mg/kg repeatability (RSDr) ranged from 1.5 % to 24.9 %, reproducibility (RSDR) ranged from 7.8 % to 29.0 % and HORRATR-values ranged from 0.5 to 1.7. The tested method showed to be suitable for the determination of 2-MCPD, 3-MCPD and glycidol in food emulsifiers consisting from mono- and diacylglycerides as well as polyglycerol polyricinoleates.
In 1990, a well-known model to predict pure component properties of triglycerides was presented by Wesdorp in “Liquid-multiple solid phase equilibria in fats: theory and experiments” and has been shown to perform well despite making thermodynamically inconsistent predictions for certain test cases. In this study, the underlying parameter set is improved to deliver more physically consistent predictions, i.e., increasing melting point and enthalpy of fusion with increasing stability of the polymorphs, without deterioration of the primary model quality to describe the available experimental data. Interestingly, when a curated dataset containing only thermodynamically consistent data is compared to a broader dataset, it appears that the model’s efficacy is highly dependent on the quantity of data, specifically the number of unsaturated triglycerides data. Quality and thermodynamic consistency of model predictions and the condition of a reliable description of monoacid triglycerides as a subset is discussed, addressing a potential interdependence.
The utilization and popularization of biodiesel are always limited by its poor cold flow properties. Both bio-based alcohol and diesel from direct coal liquefaction (DDCL) has potential to enhance the cold flow properties of biodiesel. Ternary blends of waste cooking oil biodiesel (BWCO) with DDCL and bio-based ethanol (ET) or 1-butanol (BT) for improving the cold flow properties of biodiesel. The pour point (PP), cold filter plugging point (CFPP), and cloud point (CP) of BWCO-ET, BWCO-BT, and BWCO-DDCL binary blends, and BWCO-ET-DDCL and BWCO-BT-DDCL ternary blends were comparatively assessed. Ternary phase diagrams were also applied into analyze the blending effect of the three components on the cold flow properties of biodiesel. Results showed that both DDCL, ET and BT can remarkably enhance the cold flow properties of BWCO. BT and DDCL presented a better synergistic depression effect. For ternary blends in 20:10:70 blending ratio, BWCO-BT-DDCL exhibited the lowest PP, CFPP, and CP of −23 °C, −19 °C, and −17 °C, respectively. The crystallization behavior and crystal morphology of blended fuels are also observed via a polarizing optical microscope, and find that DDCL together with BT in biodiesel can effectively retard the aggregation of large crystals and inhibit crystals growth.
De-oiled canola meals are sources of protein-containing flavor-active phenolic compounds. Conventional canola oil processing utilizes an excess amount of solvents and is associated with the release of high-intensity bitter flavor-active phenolic compounds, limiting the use of the canola meal. Recent advances in the extraction and isolation of the bitter favor-active phenolic compounds from canola by-products produce protein isolates, however, would benefit the industry by producing a side-stream ingredient rich in phenolics. High temperature and pressure-aided processing, namely the accelerated solvent extraction (ASE) was investigated to extract the flavor-active bitter molecules from the canola meal. The extractability of flavor-active phenolic compounds including the major sinapates, kaempferol derivatives, and other thermo-generative compounds including thomasidioc acid (TA) was evaluated. The effects of temperature, solvent extractant and concentration, and the particle size of the meal, were examined on the extraction efficiency of these phenolic compounds. Extraction temperature (180oC) was the primary determinant (p<0.05) for the attenuation of major sinapates including sinapine and sinapic acid. Both ethanol and methanol extractants at a concentration of 70% (v/v) significantly (p<0.05) extracted the flavor-active phenolic compounds. The pressurized high temperature through optimized ASE conditions attenuated the bitter undesirable flavor-active phenolic molecules from canola meal thereby facilitating a potential value-added phenolic-rich by-product.
Oleosins are mandatory to avoid coalescence of oil bodies (OBs), so commercial proteases are used to efficiently demulsify OBs into food oil. However, the commercial proteases and pH regulators (acid and alkali) greatly restrict this method in industry. In this study, aspartic endopeptidases, subtilisin-like proteases, metalloendopeptidase, and serine carboxypeptidases were identified in isolated sesame OBs by liquid chromatography tandem mass spectrometry (LC–MS/MS). Tricine–sodium dodecyl sulfate–polyacrylamide gel electrophoresis and protease inhibitor assay revealed that aspartic endopeptidases exerted high activity against oleosins in a pH range of 3−6 and a temperature range of 40−70 °C, while subtilisin-like proteases exhibited sharp optimum at pH 5. Metalloendopeptidase contributed to the low activity against oleosins at pH 7−9. Trichloroacetic acid–nitrogen soluble index and free amino acid analyses quantitatively revealed that the activity of serine carboxypeptidases was high at pH 3−5, and optimal at pH 4; the combined activity of aspartic endopeptidases and subtilisin-like proteases was optimal at pH 5. By incubating the isolated sesame OBs at pH 5 and 60 °C for 2 h, approximately 97% of total lipids were recovered as free oil. At last, LC−MS/MS analysis gave deep insight into the intrinsic proteins of sesame OBs: three kinds of oleosins with molecular weights around 17 kDa, and four kinds around 15 kDa; besides 27 kDa caleosin, four kinds of oil body-associated proteins and one kind of peroxygenase-like protein also around 27 kDa; in addition to 39 kDa steroleosin, 11-beta-hydroxysteroid dehydrogenase-like 6 also around 39 kDa.
The photoprotective skincare products are in high demand to meet the consumer market with concern on skin health. Seed oils are commonly used as ingredients in many cosmetic products due to their natural antioxidants and now being increasingly recognised for their effects on skin health and photoprotection. This article briefly reviews the application of seed oils in sunscreen development focusing on the antioxidants that contribute to photoprotection, thus preventing UV-induced erythema and photoaging. The addition of seed oils that contain specific natural bioactive compounds were discussed in the review. Besides that, seed oils acting in molecular pathways that benefit in photoprotection were also summarized. Seed oils (pomegranate seed oil, castor oil, cocoa butter, jojoba oil, rosehip oil, grapeseed oil, kenaf seed oil and pumpkin seed oil) utilization have high potential to act as natural UV filters and at the same time help in skin repairing. The seed oils contributed beneficial properties to the sunscreen formulation by their synergistic effect with antioxidants, antiaging properties, anti-inflammatory effect, and potential hormetic effect. The finding of specific bioactive compound from seed oils provide better understanding on the contribution of seed oils in sunscreen formulation.
Odd chain fatty acids (C15:0 and C17:0) from dairy fat as well as odd chain phenolic lipids (alkylresorcinols) from whole grain are commonly reviewed as candidate biomarkers for dietary analysis and their ingestion are inversely related to chronic disease risks. Therefore, low levels of dietary intake of these odd chain molecules may be related to higher risk of physiological states that cause chronic diseases or mortality. It is a prerequisite to examine and understand their main role in beneficial health effects in disease prevention. We propose odd chain fatty acids (OC-FA) and most importantly odd chain phenolic lipids (OC-PL) as potential essential dietary compounds since they play key roles in physiological mechanisms. This review evaluates potential roles of OC-FA and OC-PL in mitigating chronic diseases in vitro and in vivo studies to support our hypothesis for odd chain molecules as essential dietary lipids. Further studies are needed to investigate the relationship between reduced intake of OC-FA and OC-PL containing foods and susceptibilities to chronic diseases.
Seeds of Lithospermum officinale L. from different climatic zones were analyzed looking for new sources γ-linolenic acid (GLA, 18:3n-6) and stearidonic acid (SDA, 18:4n-3). Cultured B. officinalis was also analyzed with comparative purposes. Analyses were conducted for fatty acid (FA) profiles in the whole seeds and in the neutral and polar lipids by GC; lipid classes by open column chromatography and preparative TLC; and tocopherols, sterols and phenolic compounds by HPLC-DAD, and the later compounds were confirmed by LC-MS. The richest GLA sample was L. officinale from St. Petersburg Botanical Garden (17.9% of total FA), while wild-growing L. officinale from the Rostov region showed the highest percentage of SDA (17.2% of total FA). Total FA content ranged from 11.3 to 20.8% of seed weight. Neutral and polar lipids accounted for ~98 and 2.27% of total lipids. Five neutral lipid classes were identified (% of NL): triterpene esters, 1.3; triacylglycerols, 93.1; free FA, 1.8; diacylglycerols, 1.4; and monoacylglycerols, 2.4. Tocopherols and sterols reached 35.7 and 83.8 mg/100 g seeds; γ-tocopherol was the main tocopherol detected, and Δ5-avenasterol was the predominant sterol. L. officinale seeds contain high amounts of phenolic compounds (389.9 mg/100 g as upper limit), in which rosmarinic acid was the main component. Overall, all data suggest the possibility of using L. officinale seed oil in pharmaceutical and cosmetic formulae and as functional food.
Poor cold flow property is a major issue that hinders the application of biodiesel-diesel blends. In this work, a series of methacrylate-benzyl methacrylate-N-vinyl-2-pyrrolidone terpolymers (RMC-MB-NVP, R= C12, C14, C16, C18) was synthesized and used as the pour point depressants (PPDs) for waste cooking oil biodiesel blends. To further improve their depressive effects, dispersants, including Tween (40, 60, and 80), Span (40, 60, and 80), phthalic acid esters (PAEs), and fatty alcohol polyoxyethylene ether (FAPE; FAPE 5, FAPE 7, and FAPE 9), were optimized and combined with the C14MC-MB-NVP terpolymers. The effects of C14MC-MB-NVP terpolymers and combined PPDs (PPDC) on the cloud point (CP), cold filter-plugging point (CFPP), and pour point (PP) of biodiesel blends were studied. Here, results showed that the presence of dispersants can efficiently enhance the solubility and dispersibility of polymeric PPDs in biodiesel blends; thus, the PPDC presents better depressive effects. Among of them, C16MC-MB-NVP (5:1:1) combined with FAPE 7 dispersant at 4:1 mass ratio (PPDC-FAPE 7) showed the best synergistic effect, and the CP, CFPP, and PP of B20 treated with 2000 ppm PPDC-FAPE 7 decreased by 4, 10 and 19 °C, respectively. Moreover, differential scanning calorimetry, polarizing optical microscope and rheological analyses were performed to rationalize the action mechanism of these PPDs and dispersants in biodiesel blends.
Linseeds contains high levels of PUFA α-linolenic acid, naturally protected against thermal oxidation by their encapsulation within LS oil bodies by multiple components including antioxidant proteins and mucilage emulsifying agents. By LS grinding, adding of water, adjusting pH, and sonication LS oil bodies emulsions (LSE) can be formed which can also encapsulate externally added PUFAs, to minimize their thermal oxidation, as it does for the intrinsic ALA PUFAs. Fish oil encapsulation into this LSE platform (LSFE) offers the possibility of a nutritive delivery system of the biologically essential PUFA fish oil’s, protected from oxidation, which to date is difficult to achieve. In this study structural and chemical properties LF 1H NMR T1-T2 characterization of LSE and LSFE was used to analyze their stability and changes, under thermal oxidizing conditions. Peak changes in these LF 1H-NMR spectra were correlated with the stability of chemical and physical variables during thermal (55oC for 96 hrs) oxidation. The present study demonstrates the capability of 1H LF-NMR relaxation sensor to monitor the time domain fingerprints of chemical and structural changes of LSE and with co-encapsulated fish oil (LSFE) under thermal autoxidation conditions. The results of the LF-1H NMR analysis are further supported and correlated with conventional peroxide value tests, self-diffusion, droplets size distribution, zeta potential estimation of surface stability under thermal oxidation conditions. The results of this study demonstrate the efficacy of LSE to minimize linseed and encapsulated fish oil PUFA oxidation.
The food industry is seeking natural antioxidants for edible oils that have comparable activity to synthetic counterparts. In this study, Osage orange extract (OOE) rich in osajin (42.9%) and pomiferin (30.0%) was obtained after hexane extraction of the fruit, and its antioxidant activity was examined in stripped soybean oil (SBO) and fish oil (FO), in which antioxidants and polar compounds were removed. The antioxidant activity of OOE was compared with commercial natural antioxidants (i.e., rosemary extract and mixed tocopherols) and a synthetic antioxidant, butylated hydroxytoluene (BHT), during storage at 25 and 40 ℃. The 0.1% OOE had stronger antioxidant activity than 0.1% rosemary extract and 0.1% mixed tocopherols in both oils at 25 and 40 ℃. Its activity was similar to 0.02% BHT in SBO and was similar or slightly stronger than 0.02% BHT in FO. When OOE was studied at 0.05, 0.1, and 0.2%, there was a weak dose-response in SBO but a stronger dose-response in FO. Headspace volatile analysis using solid phase micro-extraction (SPME) combined with GC-MS indicated that 0.1% OOE was very effective in preventing the formation of volatile oxidation products in both oils. Although it should be further tested for safety before the actual use, this study shows that OOE can be developed as an antioxidant for edible oils.
The relation between the speed of sound (u) in biodiesel and the change in Gibbs energy (G) has not been described in the literature. With the method of Gibbs energy additivity, the relation between u and G can be expressed as ln(u2) = G/RT + A, where R is the universal gas constant, T is the absolute temperature, and A is a constant. Further expansion of G into its enthalpy and entropy, and sub-dividing the molecule of a fatty and methyl ester (FAME) into groups of atoms, the final model is good for estimating the speed of sound in both FAME and biodiesel at various temperatures. Only the numbers of double bonds and carbon atoms of the fatty acid are required for the calculation.
Epoxidized methyl esters (EMO) with their high oxirane ring reactivity, acts as a raw material in the synthesis of various industrial chemicals including polymers, stabilizers, plasticizers, glycols, polyols, carbonyl compounds, biolubricants etc. EMO has been generally quantified by the gas chromatography (GC) and high performance liquid chromatography (HPLC) techniques. Taking into the account of the limitations of these techniques, two qHNMR based equations have been proposed for the quantification of EMO in the mixture of EMO and methyl esters (MO). The validity of the proposed method was determined using standard mixtures of MO and EMO having different molar concentrations. The developed equations have been applied on the samples of EMO prepared from oleic acid in two step process viz., esterification followed by epoxidation. The qHNMR based EMO quantification showed acceptable agreement with the results obtained from HPLC analysis.
This work presents an original approach to develop an integrated process to improve the nutritional characteristics of natural oils, starting with the extraction from the raw material by environmentally friendly methods and following with the production of novel acylglycerols using immobilized lipases. Specifically, 2-monoacylglycerols (2-MAGs) enriched in the omega-3 stearidonic acid (SDA) were synthesized by selective ethanolysis of extracted Echium plantagineum oil using the lipase from Thermomyces lanuginosus (TLL). Different reaction conditions were investigated to minimize the undesirable acyl migration and to ensure the purity of final products. The biocatalyst produced in our laboratory by the immobilization of TLL on a hydrophobic support reached the maximum theoretical amount of 2-MAG in only 2 h at mild reaction conditions, achieving a product enriched in omega 3 SDA (up to 25%). Moreover, the produced biocatalyst exhibited higher stability than commercial lipases. The average activity after 5 cycles was 71%, allowing several reutilization cycles and developing a feasible enzymatic process. Finally, 2-MAGs was used as starting material to synthesize structured triacyclglycerols (STAGs) in solvent-free systems. The use of molecular sieves in combination with the immobilized lipase from Rhizomucor miehei (RML) showed to be an extraordinarily fast strategy to produce pure STAGs (100% in 1h), 4 times higher than the activity showed by the commercial derivative. Thus, the enzymatic processes developed in this study open a range of possibilities to synthesize omega-3 acylglycerols with improved characteristics for essential biological functions and nutritional advantages, proving the usefulness of immobilized lipases to produce novel functional lipid.
The application of nanostructured lipid carrier (NLC) in UV filters encapsulation was found to enhance its safe use. In this work, kenaf seed oil-NLC (KSO-NLC) co-loaded with UV filters encapsulated was used as an active ingredient in α-tocopherol cream to develop a photoprotective prototype. It was then subjected to further analysis to determine the physical properties storage stability and cytotoxicity. The ratio of KSO-NLC to α-tocopherol cream was optimised based on the SPF value using UV transmittance analyser. The physical properties of the samples were analysed and the amount of α-tocopherol was quantified by ultra-high performance liquid chromatography (UHPLC). The optimised sample was then evaluated for in vitro antioxidant activities using DPPH and ABTS assays. Meanwhile, in vitro cytotoxicity was studied on normal human dermal fibroblast (NHDF) cell line using MTT and CCK-8 assays. The sample produced by KSO-NLC to α-tocopherol cream in ratio 1:2 (N3) showed SPF value > 50. Besides, the samples showed microbial stability and sustainable α-tocopherol content upon 12 weeks of storage. The cytotoxicity evaluation of N3 and α-tocopherol cream (N5) showed > 100 % cell proliferation indicated there is no side effect on the cell growth, yet it triggered the cell proliferation with the presence of bioactive compounds. Overall, the results herein gathered are very promising towards the development of new green cosmetic formulations with the utilisation of KSO-NLC and palm-based α-tocopherol cream.
Oleogels prepared from hydrocolloids have recently gained a lot of attention as an alternative for trans and saturated fats. Previously we have demonstrated that the freeze-dried foams prepared using a mixture of 5% faba bean or pea protein concentrates with 0.25% xanthan gum at pH 7 and 9 can hold canola oil 30-40 times their weights (Mohanan, Tang, Nickerson and Ghosh, 2020). However, the oleogels suffered from high oil loss, about 30% oil leaked, which negatively affected the rheological properties of the oleogels. The functionality of the cake baked using the oleogels was poorer compared to a shortening baked cake. The present study explored the addition of a small amount of high-melting monoacylglycerol (MAG) and candelilla wax (CW) on reducing oil loss, improving rheological properties and baking qualities of pulse protein-stabilized oleogels. Different concentrations (0.5-3%) of MAG or CW were dissolved in canola oil at 80 ºC. The hot oil was then added into the freeze-dried protein-polysaccharide foams (pH 7) and quickly transferred to a refrigerator. The crystallized additives reinforced the oleogel network, thereby reducing oil loss while increasing the firmness, cohesiveness, and storage modulus. When model cakes were baked with the oleogels, significant improvement in textural properties was observed with the addition of MAG in the foam-templated oleogels. However, in comparison with shortening-based cakes, oleogel-based cakes still showed a negative effect on hardness, chewiness and cohesiveness.
High voltage atmospheric cold plasma (HVACP) treatment generates reactive gas species that induce inter and intramolecular reactions in soybean oil. The goal of this study is to analyze the effect of HVACP treatment on the chemical structure of soybean oil in a hydrogen gas environment at atmospheric pressure. HVACP was used to treat soybean oil (15g), for up to 6h by triplicate. Plasma generated reactive gas species interact with the sample producing three distinct fractions identified as a liquid, gel, and solid. Fatty acid profile, FTIR, 1H-NMR/13C-NMR, GPC, thermal properties and peroxide value, were used to characterize the chemical structure. Results indicated a lower content of polyunsaturated fatty acids, increased content of saturated fatty acids, and the presence of isomers. An insoluble portion was observed in the solid fraction and increase with treatment time up to 42% in the 6h treated samples. Plasma species may cause two main reactions: polymerization and hydrogenation.