Showing papers in "European Journal of Lipid Science and Technology in 2010"

Castor oil as a renewable resource for the chemical industry

Abstract: Castor oil is, as many other plant oils, a very valuable renewable resource for the chemical industry. This review article provides an overview on this specialty oil, covering its production and properties. More importantly, the preparation, properties and major application possibilities of chemical derivatives of castor oil are highlighted. Our discussion focuses on application possibilities of castor oil and its derivatives for the synthesis of renewable monomers and polymers. An overview of recent developments in this field is provided and selected examples are discussed in detail, including the preparation and characterization of castor oil-derived polyurethanes, polyesters and polyamides.

Novel antioxidants in food quality preservation and health promotion.

Abstract: Autoxidation in food and biological systems is responsible for a multitude of adverse effects and implications in human health as well as in food stability and preservation. Antioxidants play a major role in preventing or delaying autoxidation and have attracted much attention as food stabilizers, dietary supplements and natural health products. Both synthetic and natural antioxidants are widely used in food products and an ever increasing number of research papers have appeared in the recent literature on the discovery and application of natural antioxidants and their therapeutic use in inhibiting a myriad of diseases. However, some common synthetic antioxidants have also become controversial due to their potential adverse effects on health. This overview provides the latest developments about novel antioxidants, particularly phenolic derivatives, peptides/protein hydrolysates, phospholipids and polysaccharides, and their role in food quality preservation and human health promotion.

Biolubricants: raw materials, chemical modifications and environmental benefits.

Abstract: The depletion of the world's crude oil reserve, increasing crude oil prices, and issues related to conservation have brought about renewed interest in the use of bio-based materials. Emphasis on the development of renewable, biodegradable, and environmentally friendly industrial fluids, such as lubricants, has resulted in the widespread use of natural oils and fats for non-edible purposes. In this study, we have reviewed the available literature and recently published data related to bio-based raw materials and the chemical modifications of raw materials. Additionally, we have analyzed the impacts and benefits of the use of bio-based raw materials as functional fluids or biolubricants. The term biolubricants applies to all lubricants, which are both rapidly biodegradable and non-toxic to humans and other living organisms, especially in aquatic environments. Biodegradability provides an indication of the persistence of the substance in the environment and is the yardstick for assessing the eco-friendliness of substances. Scientists are discovering economical and safe ways to improve the properties of biolubricants, such as increasing their poor oxidative stability and decreasing high pour points. “Green” biolubricants must be used for all applications where there is an environmental risk.

Production and applications of trehalose lipid biosurfactants

Abstract: Different types of trehalose containing glycolipids are known to be produced by several microorganisms belonging to the mycolates group, such as Mycobacterium, Rhodococcus, Arthrobacter, Nocardia and Gordonia. Different structures have been elucidated particularly in Rhodococcus genus. Trehalolipids have gained increased interest for their potential applications in a number of fields due to their ability to lower interfacial tension and increase pseudosolubility of hydrophobic compounds. The most widespread application is in bioremediation technologies as such compounds are known to enhance bioavailability of hydrocarbons. In comparison to other microbial glycolipids, trehalolipids have generally showed contrasting results and achievements with both cases of inhibition and enhancement of biodegradation rates. One of the important challenges regarding potential use of trehalose lipids in a variety of applications is the optimisation of their production and downstream processing. In fact, the purification of the target biological compounds by downstream processing can account for over half the production cost in many biotechnology applications. This is especially true in the case of the Rhodococcal glycolipids, which are often bound to cellular envelopes and are usually produced along with other surface active lipids. In this review, we highlight the current knowledge of trehalolipid biosurfactant applications and the latest successful strategies employed to reduce the cost of their production.

Fatty acid esters of glycidol in refined fats and oils

Abstract: Discrepancies in the analysis of 3-chloropropane-1,2-diol (3-MCPD) esters can be explained by the hypothesis that in some refined oils significant amounts of fatty acid esters of glycidol (glycidyl esters) are present in addition to 3-MCPD esters. Glycidyl esters were separated from triacylglycerols by gel permeation chromatography (GPC) and detected by gas chromatography-mass spectrometry (GC-MS). Six samples of palm oil and palm oil-based fats were analyzed by GPC and GC-MS. In chromatograms of all samples, significant peaks, retention time and mass spectra in conformity with self-synthesized glycidyl palmitate and glycidyl oleate were detectable. Quantification of individual glycidyl esters was not possible because of a lack of pure standards. Concentration of ester-bound glycidol in different samples of fats and oils was estimated using an indirect difference method. Glycidyl esters could be detected only in refined, but not in crude or native, fats and oils. The highest concentrations were detected in palm oil and palm oil-based fats. In a palm oil sample, glycidyl ester concentration varied according to different deodorization parameters, temperature, and time, while 3-MCPD ester concentration was relatively constant, indicating that mitigation of glycidyl esters possibly may be achieved by optimizing refining parameters.

Yarrowia lipolytica: A model microorganism used for the production of tailor‐made lipids

Abstract: This paper presents a review of studies related with the production of specialty lipids by the yeast Yarrowia lipolytica during growth on various fatty agro-industrial residues utilized as substrates. In a first approach, the potential for growth on stearin (a low-cost industrial derivative of tallow composed of saturated free fatty acids) was assessed; significant biomass production was obtained, accompanied by notable intracellular accumulation of lipid which occurred as a primary anabolic activity regardless of the extracellular nitrogen availability in the medium. Y. lipolytica consumed its own storage lipids in the stationary growth phase. The secretion of extracellular lipase in non-negligible quantities was also observed in cultures performed on stearin. Although Y. lipolytica tended to increase the intracellular level of stearic acid, its reserve lipid could be used as a cocoa butter substitute, provided that an oleic acid donor, such as chemically hydrolyzed rapeseed oil, is used as co-substrate together with stearin. Accordingly, predetermined lipids with composition similarities to cocoa butter were synthesized using low-cost substrates. Other strategies related with the production of microbial cocoa butter substitutes are also presented and comprehensively discussed.

Vegetable oil-based thermosetting polymers.

Abstract: Vegetable oils are excellent renewable raw materials for thermosetting polymers. By the direct polymerization of triglyceride C=C, we obtained organic-inorganic hybrid materials with promising properties for optical applications by the hydrosilylation of alkenyl-terminated fatty acid derivatives. The presence of double bonds in triglycerides makes it possible to attach some functional groups through chemical modification, and we describe various chemical pathways for functionalizing triglycerides and fatty acids. Epoxidation is one of the most interesting chemical modifications that leads to epoxidized vegetable oils. We report the preparation of biobased polyhedral oligomeric silsesquioxanes-nanocomposites from epoxidized linseed oil. Moreover, we describe the preparation of a new family of epoxidized methyl oleate-based polyether polyols, which were used in the synthesis of polyurethanes with specific applications: silicon-containing polyurethanes with enhanced flame-retardant properties and polyurethane networks with potential applications in biomedicine. An enone-containing triglyceride derivative was obtained, by an environmentally friendly chemical procedure from high oleic sunflower oil that could be cross-linked with diamines. In a similar way, triglycerides containing secondary allylic alcohols can be obtained that can be further functionalized with acrylate or phosphorus-containing derivatives to obtain flame-retardant thermosets.

Kinetic study of β‐carotene and lutein degradation in oils during heat treatment

Abstract: The kinetics of trans-beta-carotene and trans-lutein degradation were individually investigated in palm olein and Vegetaline (R), at four temperatures ranging from 120 to 180 degrees C. HPLC-DAD analysis was carried out to monitor trans and cis carotenoid variations over the heating time at each temperature. In both oils, initial trans-beta-carotene and trans-lutein degradation rates increased with temperature. Trans-lutein was found to degrade at a slower rate than trans-beta-carotene, suggesting a higher thermal resistance. The isomers identified were 13-cis- and 9-cis-beta-carotene, and 13-cis-, 9-cis-, 13'-cis-, and 9'-cis-lutein. In spite of the higher number of lutein cis isomers, their total amount was lower than that of beta-carotene cis isomers. Trans and cis carotenoids were involved in degradation reactions at rates that increased with temperature. All degradation rates were generally found to be lower in Vegetaline (R) than in palm olein. These results were explained by the initial composition of the two oils and especially their peroxide and vitamin E contents.

The refinement of renewable resources: new important derivatives of fatty acids and glycerol.

Abstract: During the last years, the industrial significance of renewable resources has highly increased. The ever-growing use of fossil resources for energy consumption, polymers, fine chemicals and pharmaceuticals and the therefore steadily increasing price favour the substitution of oil and gas by renewable resources. Here, especially products of catalytic functionalisations of vegetable fats and oils such as rapeseed oil, sunflower oil, palm oil or coconut oil play a decisive role. The present article gives a survey of several important catalytic functionalisations of fatty compounds and glycerol resulting in new attractive products. With their emerging properties, they could find a rapid introduction into the chemical market. Particularly the functionalisations via heterogeneous and homogeneous catalysis, like additions, reductions, oxidations and metathesis reactions, will be presented.

Microencapsulation of extra‐virgin olive oil by spray‐drying: Influence of wall material and olive quality

Abstract: Encapsulation is a process by which small particles of core products are packaged within a wall material to form microcapsules. One common technique to produce encapsulated products is spray-drying which involves the conversion of liquid oils in the form of an emulsion into dry powders. Emulsification conditions, wall components, and spray-drying parameters have been optimized for the microencapsulation of different extra-virgin olive oils. To achieve this goal, the influences of emulsion conditions have been evaluated for different wall components such as proteins (sodium caseinate and gelatin), hydrocolloids (Arabic gum), and hydrolyzed starches (starch, lactose, and maltodextrin). In addition, for each of the tested conditions the ratio of wall solid-to-oil and spray-drying parameters were as well optimized. The microencapsulation effectiveness was determined based on process yield and the ratio between free and encapsulated oil (microencapsulation efficiency). Highest encapsulation yields were achieved when gelatin, Arabic gum and maltodextrin and sodium caseinate and maltodextrin were used as encapsulation agents and the ratio of wall solid-to-oil was 1:4 and 1:2, respectively. Under these conditions, 53% of oil was encapsulated. The influence of olive oil quality in the microencapsulation process was evaluated in terms of fatty acids profile alteration after the microencapsulation process.

Commercial sugars as substrates for lipid accumulation in Cunninghamella echinulata and Mortierella isabellina fungi

Abstract: Cunninghamella echinulata and Mortierella isabellina, fungi capable of accumulating single cell oil (SCO) containing γ-linolenic acid (GLA), were cultivated on sugar-based media, at initial substrate concentration 60 g/L. It was demonstrated that the carbon source plays an essential role on lipid accumulation process. Especially, on glucose, C. echinulata produced 3.9 g/L lipids containing 19.5% GLA, whereas M. isabellina achieved 9.9 g/L of lipid, containing 3.5% GLA. Growth on fructose was also satisfactory for both microorganisms. Although M. isabellina failed to grow adequately on saccharose, C. echinulata presented appreciable biomass production of 17.6 g/L, containing 18% of fat. Extra-cellular invertase activity was also detected in the case of C. echinulata cultures, achieving 0.5 U/mL. Both molds presented satisfactory growth on molasses, with significant amounts of SCO and GLA produced, accompanied by non-negligible substrate decolorization. Scaling-up in a 3-L bioreactor of M. isabellina with glucose as a substrate resulted in 17.5 g/L of biomass, containing 12.7 g/L of lipid. Finally, fractionation of cellular lipid for both strains showed that neutral lipids represented about 90-92% w/w upon total accumulated lipids, whilst fractions of glycolipids plus sphingolipids and phospholipids were 6-7 and 3-4%, respectively.

Rhamnolipid production by Burkholderia plantarii DSM 9509T

Abstract: The Burkholderia plantarii type strain DSM 9509T was shown to produce extracellular rhamnolipids that clearly differ in structure and properties from the Pseudomonas aeruginosa rhamnolipids. The type strain has not been previously described as rhamnolipid producer. B. plantarii DSM 9509 T was cultivated in a parallel bioreactor system and produced up to 45.74 mg/L of rhamnolipids when grown in glucose supplemented rich medium. The structure of the main rhamnolipid Rha 2 -C 14 -C 14 ( L -rhamnopyranosyl-L-rhamnopyranosyl-β-hydroxytetradecanoyl-β-hydroxytetradecanoate) was verified by MS/MS. The purified rhamnolipid Rha 2 -C 14 -C 14 lowered the equilibrium surface tension of distilled water to 29.4 mN/m. The CMC was between 15 and 20 mg/L. In this study, growth and product formation were investigated under biotechnological aspects. Practical applications: B. plantarii DSM 9509 T produces a rhamnolipid that differs in structure from P. aeruginosa rhamnolipids and exhibits excellent surfactant properties. An essential advantage in comparison to P. aeruginosa is that B. plantarii DSM 9509 T is a Biosafety Level 1 microorganism and is not pathogenic in humans. A biotechnological production of the Burkholderia rhamnolipids could lead to their application in detergents, pharmaceuticals, and other industries providing new products on the biosurfactant market.

Healthier lipid combination as functional ingredient influencing sensory and technological properties of low-fat frankfurters

Abstract: Oil (healthier lipid combination of olive, linseed and fish oils)-in-water emulsions stabilized with different protein systems (prepared with sodium caseinate (SC), soy protein isolate (SPI) and microbial transglutaminase (MTG)) were used as pork backfat replacers in low-fat frankfurters. Composition (proximate analysis and fatty acid profile), sensory analysis and technological (processing and purge losses, texture and colour) properties of frankfurters were analysed as affected by the type of oil-in-water emulsion and by chilling storage (2°C, 41 days). Frankfurters produced with oil combinations had lower levels of saturated fatty acids (SFA, 19.3%), similar levels of MUFA (46.9%) and higher levels of PUFA (33.6%) than control frankfurters (all pork fat) (39.3, 49.5 and 10.6%, respectively). PUFA/SFA and n-6/n-3 PUFA ratios in control sample were 0.27 and 9.27; in reformulated frankfurters the PUFA/SFA ratio was higher (1.7) and the n-6/n-3 PUFA ratio was lower (0.47). In general, frankfurters had good fat and water binding properties. Colour parameters were affected by formulation and storage time. Compared to control sample, frankfurters made with oil-in-water emulsions had higher (p<0.05) hardness, springiness and chewiness values. Emulsified oil stabilizing systems did not affect sensory characteristics of frankfurters, and all products were judged as acceptable.

Rhamnolipids: Production in bacteria other than Pseudomonas aeruginosa

Abstract: Rhamnolipids produced by Pseudomonas aeruginosa are the most studied biosurfactants due to their potential applications in a wide variety of industries and the high levels of their production. However, even though these biosurfactants are already produced at an industrial scale, the fact that P. aeruginosa is an opportunistic pathogen impose a restriction for its large scale production due to the intrinsic health hazard of the process. Other bacterial species that have been reported to be rhamnolipid producers are the pathogens Burkholderia mallei and B. pseudomallei, and recently the non-pathogenic B. thailandensis. This short review presents information on rhamnolipid production by bacteria different from P. aeruginosa, as well as some approaches that have been taken to produce rhamnolipids using non-pathogenic bacteria by genetic engineering of different bacteria. The low frequency of occurrence of rhamnolipid production among natural isolates that are not P. aeruginosa or Burkholderia, as well as the absence of orthologs of the genes involved in rhamnolipid synthesis (rhl genes) among the hundreds of sequenced bacterial genomes, suggest that the rare reported cases of these type of rhamnolipid-producing bacteria have acquired this trait through horizontal gene transfer either from P. aeruginosa or from a member of Burkholderia.

Phenolic compounds and some quality parameters of pumpkin seed oil

Abstract: Pumpkin seed oil has become a recognized source of phenolic compounds. The main aim of this paper was to evaluate the concentration of phenolic compounds and their extraction from pumpkin seed oil. The total phenolics content (TPC) measured in the pumpkin seed oil samples ranged from 24.71 to 50.93 mg GAE/kg of oil. The individual phenolics were tyrosol, vanillic acid, vanillin, luteolin and sinapic acid. Hexane and acetone were the best solvents for the washing step, and methanol for the elution of the phenolics in the solid-phase extraction (diol-SPE), whereas bleaching caused a significant increase in the TPC obtained (24.5-30.7%). Additionally, some other oil characteristics were evaluated. The mean oxidative stability of the oils (OSI) was around 4 h, with 5.43 h for the most stable oil. The maximum antioxidant capacity measured by the reduction of the DPPH radical was 62%, which was comparable to 0.16 mM Trolox equivalent. The color of the oil was expressed by L(star)a(star)b(star) coefficients and its hue and saturation. Whereas all samples had similar lightness, their rates of green, red, yellow and blue color were different. Moreover, TPC correlated negatively with lightness, b(star) and saturation (-0.49, -0.48, and -0.43), and positively with a(star) and hue (0.58 and 0.52).

Properties and industrial applications of sophorolipids

Abstract: Sophorolipids are glycolipids that can be produced by bioconversion of native and renewable feedstocks such as rapeseed oil. These attractive surfactants combine green chemistry and a lower carbon footprint without the undesirable side products or environmental downsides associated with many market reference surfactants. Sophorolipids are reported to be fully biodegradable and to have a low acute toxicity. This study demonstrates that they do not affect Daphnia reproduction, and that the chronic toxicity is an order of magnitude lower than that of reference surfactants, with a no-observed-effect concentration (NOEC) of 11.3 mg/L as compared to approximately 1 mg/L. Their minimum surface tension was found to be 32.1-34.2 mN/m depending on the method used. Sophorolipids are shown to be useful in hard surface cleaning and automatic dishwashing rinse aid formulations. This is attributed in part to their low foaming profile combined with their surface activity properties, which are of potential interest in additional applications. They combine an outstanding environmental profile with excellent performance, and are thus suitable for use in commercial household products.

Analysis of carotenoids and vitamin E in selected oilseeds, press cakes and oils

Abstract: Carotenoids and vitamin E in oils from the market - 6 rapeseed and 6 sunflower oils, half of each cold pressed and refined - and in the oils of rape, sunflower, flax and safflower as well as the respective seeds and press cakes from a local oil mill were quantified by HPLC. Furthermore, a photometric determination of carotenoid content was tested and checked against the chromatographic method. In the cold pressed oils minor amounts of xanthophylls (all-E)-lutein and (all-E)-zeaxanthin were determined. With exception of traces of (all-E)-β-carotene in cold-pressed rapeseed oil this provitamin A active compound did not occur. Cold pressed rapeseed oils contained 0.5-1.5 mg total carotenoids/100 g which was manifold the content of the further oils. Vitamin E was found in all vegetable oils at plant-typic tocopherol patterns. The photometric determination of carotenoids resulted in significantly higher concentrations compared to the HPLC. This overestimation bases on the carotenoid pattern which was validated by comparison with known high-carotenoid materials, i.e. maize flour with an abundant amount of xanthophylls and carrots with an abundant amount of carotenes.

Peanut oil: Compositional data

Abstract: The major fatty acids of peanut oil acylglycerols are palmitic (C 16:0), oleic (C18:1), and linoleic (C18:2) acids, and only a trace amount of linolenic fatty acid (C18:3) is present. Thus they have a very convenient oxidative stability and have been considered premium cooking and frying oils. This paper provides information about compositional data of peanut oil taking into account major (triacylglycerols and their fatty acids) and minor (free fatty acids, diacylglycerols, phospholipids, sterols, tocopherols, tocotrienols, triterpenic and aliphatic alcohols, waxes, pigments, phenolic compounds, volatiles, and metals) compounds. Moreover, the influence of genotype, seed maturity, climatic conditions, and growth location on peanut oil chemical composition is considered in the present report. In addition, peanut oils from wild species found in South America as well as from peanut lines developed through conventional breeding are also compared.

Healthier lipid combination oil‐in‐water emulsions prepared with various protein systems: an approach for development of functional meat products

Abstract: Five protein-stabilized oil-in-water emulsions were prepared using sodium caseinate (O/SC), soy protein isolate (O/SPI), sodium caseinate and microbial transglutaminase (O/SC + MTG), sodium caseinate, microbial transglutaminase and meat slurry (O/SC + MTG + MS) and SPI, sodium caseinate and microbial transglutaminase (O/IPS + SC + MTG); their composition (proximate analysis and fatty acid profile) and physicochemical characteristics were examined. The lipid phase was a combination of healthy fatty acids from olive, linseed and fish oils, containing low proportions (15%) of saturated fatty acids (SFA) and high proportions of monounsaturated fatty acids (MUFA, 47%) and polyunsaturated fatty acids (PUFA, 36%), with a PUFA/SFA ratio >2, and a n-6/n-3 PUFA ratio of 0.4. All the oil-in-water emulsions showed high thermal and creamy stability. Results of penetration test and dynamic rheological properties showed la existencia de different types of oil-in-water emulsion structures according to stabilizing system of emulsion. Those structures ranged from concentrate solution-like (stabilized only with SC) (gel strength 0.06 mJ) to gel-like (samples containing MTG) behaviours (gel strength ranged between 3.4 and 6.2 mJ). Morphological differences in the organization of the network structure were observed (by scanning electron microscopy) as functions of the protein system used to stabilize the oil-in-water emulsions.

Stability of refined olive oil and olive-pomace oil added by phenolic compounds from olive leaves.

Abstract: Refined olive oil and olive-pomace oil were enriched with olive leaf phenolic compounds in order to enhance its quality and bring it closer to virgin olive oil. The changes that occurred in the concentrations of pure oleuropein, oleuropein aglycone, hydroxytyrosol acetyl and α-tocopherol at 400 µg/kg of oil during the storage of refined olive oil and olive-pomace oil under accelerated conditions (50 °C) were investigated. In a period of 4 months, α-tocopherol decomposed by 75% whereas less than 40% of the phenols were lost. During storage, enzymatic olive leaf extract hydrolysate that contains two major compounds, hydroxytyrosol and oleuropein aglycone showed the highest antioxidant activity and the lowest detected stability, followed by oleuropein. The oleuropein in olive leaf extracts exhibited similar degradation profiles, reducing by 60–50% and 80% for the olive oil and olive-pomace oil in 6 months, respectively. The acetylated extract, however, displayed a loss of 10 and 5% in olive oil and olive-pomace oil, respectively. In the fatty acid composition, an increase in oleic acid and a decrease in linoleic acid were observed. The antiradical activities of the olive oil and olive-pomace oil enriched with olive leaf phenolic compounds at 400 ppm showed that enzymatic hydrolysate extract had the highest protective effect against oil oxidation. Based on the Rancimat method, the oils with added leaf enzymatic hydrolysate extract had the lowest peroxide value and the highest stability. After 6 months of storage and at 120 °C, the oxidative resistance of refined olive oil and olive-pomace oil reached 0.71 and 0.89 h, respectively, whereas that of the non-enriched samples fell to zero.

Vegetable oil-based triols from hydroformylated fatty acids and polyurethane elastomers

Abstract: Novel bio-based polyols were prepared from hydroformylated oleic acid (9/10-hydroxymethyl-octadecanoic acid) methyl esters (HFME) and trimethylolpropane by transesterification. Hydroformylation produces primary hydroxyls, which allow relatively lower transesterification temperatures and better yields than hydroxy fatty acids with secondary hydroxyl groups. These non-crystallizing polyols have no double bonds and their viscosities are acceptable. Polyurethane (PU) elastomers prepared by reaction of these polyols with diphenylmethane diisocyanate had glass transition temperatures from -33 to -56 °C, depending on the molecular weight of the triols. Tensile strength and Shore A hardness were higher, and elongation, swelling and sol fraction lower than those of corresponding networks from polyricinoleic acid polyols. The plasticizing effect of longer dangling chains in HFME-based PU compensated, to a degree, the presence of double bonds in ricinoleic acid, effectively resulting in similar glass transitions between the two families of polyols.

Oxidative stability of Echium plantagineum seed oil bodies

Abstract: Echium plantagineum seed contains a highly polyunsaturated oil (approximately 14% linoleic acid, 10% γ-linolenic acid, 33% α-linolenic acid and 14% stearidonic acid); almost half of the fatty acids are omega-3 fatty acids, so there is an interest in the possible health benefits of this oil, which, once extracted, is prone to oxidation. For the first time in reported literature, oil bodies (OBs), the organelles that store the oil in mature seed, were recovered from E. plantagineum seeds. The oxidative stability of these organelles ex vivo, dispersed in an aqueous continuous phase, was tested against processed E. plantagineum oil emulsions stabilised with either SDS or Tween 20. For both primary and secondary oxidation products the OBs were the most stable form of dispersed oil, and the dispersed systems were all more stable than bulk E. plantagineum oil after incubating at 40°C for 7 days. The possible reasons for the enhanced chemical stability of E. plantagineum OBs are explored in this paper. Practical applications: OBs, the natural store of oil in oilseeds, can be recovered from seeds intact and are relatively stable to oxidation ex vivo. Echium seed OBs, enriched in physiologically active omega-3 fatty acids, therefore offer an attractive alternative to traditional oil extraction methods and overcome the need to encapsulate the omega-3 rich oil.

Changes in virgin olive oil characteristics during different storage conditions

Abstract: In this study we have examined the effect of olive oil storage outdoors on a comprehensive series of quality measures. The conditions used were at the extreme of those encountered during the production of bottle oil. Filtered and unfiltered oils were compared as was the influence of inert gas (nitrogen) in the headspace. Increases in K232, K270 and peroxides over time were very much reduced by inert headspace gas, which also reduced losses of total phenols and oxidative stability. Headspace nitrogen also reduced the rise in unconjugated phenolics as secoiridoid derivatives declined and minimised losses in polyunsaturated fatty acids. The pattern of volatile compounds detected in olive oils stored indoors or outdoors showed subtle differences. Moreover, when stored with air exposure the levels of some negative sensory components such as penten-3-ol and hexanal increased while other positives, like trans-2-hexenal were reduced. These changes would be expected to reduce quality. Finally, Panel tests were used. All oils lost perceived quality on storage and this was accelerated outdoors while headspace nitrogen slowed the deterioration significantly. Our data show that storage outdoors for 4 months in winter does not reduce olive oil quality significantly and that an inert gas in the headspace is beneficial.

Effect of feeding and genotype on the lipid profile of organic chicken meat

Abstract: The effects of partial substitution of soybean (SB) with faba bean (FB) and of genotypes [fast-growing Cobb 700 (FG), medium-growing naked-neck Kabir (MG), slow-growing Brown Classic Lohman (SG)] on the lipid composition as well as the meat quality attributes of chickens reared under organic conditions were evaluated. A total of 720 1-day-old male chicks were equally divided into three groups according to genotype and raised for 81 (MG and FG) or 96 days (SG): half birds of each genotype received either SB grower diet or FB grower diet. Meat from SG and MG birds exhibited a lower lipid content than that from FG birds. Both in breast and thigh meat, MUFA were significantly increased from SG to MG and FG. SG meat contained the highest amounts of either arachidonic acid, eicosapentaenoic acid, docosahexaenoic acid, or docosapentaenoic acid, but the lowest amounts of α-linolenic acid. Total PUFA gradually decreased from SG to MG and FG birds (413, 358, and 324 g/kg of fat), as well as total n ― 6 and total n ― 3. The Δ 5 - plus Δ 6 -desaturase index was 54.0, 34.4, and 23.6 for SG, MG, and FG birds, respectively. The n — 6/n — 3 ratio was lower in SG and MG than in FG birds. The partial replacement of SB with FB had a lesser effect than the genotype on the meat quality characteristics.

Kinetics of commercial olive oil oxidation: dynamic differential scanning calorimetry and Rancimat studies.

Abstract: Four samples of olive oil were oxidized under polythermal (dynamic) conditions in the cell of a normal-pressure differential scanning calorimeter (DSC) and in the Metrohm Rancimat apparatus. The DSC experiments were carried out in an oxygen flow atmosphere using different linearly programmed heating rates in the range of 4–20 °C/min. Through DSC exotherms, the extrapolated onset temperatures were determined and used for the assessment of the thermal-oxidative stabilities of the samples. Using the Ozawa-Flynn-Wall method and the Arrhenius equation, the activation energies (Ea), pre-exponential factors (Z) and reaction rate constants (k) for oil oxidation under DSC conditions were calculated. The Rancimat measurements of oxidation induction times were carried out under isothermal conditions in an air atmosphere at temperatures from 100 to 140 °C with intervals of 10 °C. Using the Arrhenius-type correlation between the inverse of the induction times and the absolute temperature of the measurements, Ea, Z, and k for oil oxidation under Rancimat conditions were calculated. The primary kinetic parameters derived from both methods were qualitatively consistent and they help to evaluate the oxidative stabilities of oils at increased temperatures.

Protein engineering and discovery of lipases

Abstract: Lipases are widely used in the modification of fats and oils with applications in the production of structured triacylglycerols, selective isolation or incorporation of specific fatty acids, and in oleochemistry for the synthesis of emollient esters and sugar fatty acid esters. Despite the numerous examples for the effective use of lipases, the biocatalysts often need to be optimized to show the desired specificities, stability, operational properties, etc. Beside rather classical methods such as variation of the solvent system or carrier for immobilization, the use of protein engineering methods to modify the protein on a molecular level is an important tool for the creation of tailor-designed enzymes. Protein design is also complemented with the efficient isolation of novel lipases from the metagenome. This article covers concepts and examples for the discovery of novel lipases and their variants by protein engineering and metagenome techniques.

Esters of calendula oil and tung oil as reactive diluents for alkyd resins

Abstract: A simple protocol for the transesterification of highly unsaturated vegetable oils such as calendula oil and tung oil, catalyzed by sodium methoxide, is described. Calendula oil contained about 59-65% of calendic acid (8,10-trans,12-cis-octadecatrienoic acid) (1a), and tung oil about 84% of α-eleostearic acid (9-cis,11,13-trans-octadecatrienoic acid) (2a). Transesterifications of calendula oil with alcohols such as methanol, ethanol, and isopropanol give the respective calendula oil esters, which were tested as reactive diluents for alkyd resins in coating formulations. Especially ethyl and isopropyl calendula oil esters showed good properties, including low viscosity and good drying performance. Furthermore, a shortening of the drying time of about 35-40% compared to conventionally prepared formulations was achieved. Analogously, the respective esters of tung oil were synthesized and used as reactive diluent.

Biocompatible surfactants from renewable hydrophiles

Abstract: Significant advances made by the authors in the field of cationic surfactants derived from arginine and lysine hydrophilic sources of different structure are reviewed Linear, gemini and glycerolipid-like structures with polar groups consisting of Arg or Lys amino acids are described Our multidisciplinary approach includes design, synthesis, adsorption at interfaces and self-assembly behavior, antimicrobial activity, and studies of biocompatibility including ecotoxicity, biodegradability and irritation effects Considering the green chemistry principles, the synthesis contemplates the preparation of more efficient and safer surfactants using renewable raw materials for the synthesis of surfactants: proteins, peptides, amino acids and triacylglycerols, using biocatalysis as condensating methodology, and designing for biodegradation Also in order to increase the efficiency of these compounds, a complete characterization including self-assembly, ecotoxicity, biodegradability, and studies of mechanisms of toxicity has been carried out The structure of the surfactant molecule affects micellization and not the nature of the polar head (Arg or Lys) The critical micelle concentrations of the gemini surfactants are three orders of magnitude lower than the linear ones for the same alkyl chain length The presence of a cationic charge in the amino acid provides antimicrobial activity to these compounds

Biodegradation and utilization of waste cooking oil by Yarrowia lipolytica CECT 1240

Abstract: Biodegradation of waste cooking oil and its application as lipase production inducer in cultures of Yarrowia lipolytica CECT 1240 have been investigated, both in shake flasks and a bench-scale bioreactor. The ability of this strain to degrade the spent oil was evaluated by monitoring COD throughout the cultures, and a remarkable decrease was recorded (almost 90% decrease in oil COD after 3 days in bioreactor). Moreover, the addition of waste cooking oil to the medium led to a significant augmentation in extracellular lipase production by the yeast, compared to oil-free cultures. This confirms the suitability of the studied residue as an inducer of lipase biosynthesis, which is a very interesting fact, from an economic standpoint. These results were confirmed when a fed-batch strategy was proposed. Finally, some properties of the crude enzyme were studied, and compared to the enzymes obtained when non-used oil was added to the medium. Practical application: New strategies to valorize wastes from the food and agro industries are attracting a great scientific interest due to the important advantages offered from an economic and environmental point of view. For this reason, the yeast Yarrowia lipolytica CECT 1240 is proposed for degrading waste cooking oils. This approach entails also another benefit in terms of lipolytic enzyme synthesis, since the addition of used up oils has a lipase inducer effect. The enormous interest in lipases is reflected in the number of applications that they present. The process was successfully carried out both in shake flasks and a bench-scale bioreactor, allowing producing high levels of lipolytic activity at the same time that the COD was diminished up to nearly 90%.

Rapid FTIR determination of water, phenolics and antioxidant activity of olive oil

Abstract: A rapid Fourier transformed infrared (FTIR) attenuated total reflectance (ATR) spectroscopic method was applied to the determination of water content (WC), total phenol amount (TP) and antioxidant activity (ABTS .+ ) of virgin olive oils (VOO) and olive oils. Calibration models were constructed using partial least squares regression. Oil samples with WC ranging from 289 to 1402 mg water/kg oil, with TP from 46 to 877 mg gallic acid/kg oil and with ABTS .+ from 0 to 5.7 mmol Trolox/kg oil were considered for chemometric analysis. Better results were obtained when selecting suitable spectral ranges; in particular, from 2260 to 1008 cm -1 for WC, from 3610 to 816 cm -1 for TP and from 3707 to 1105 cm -1 for ABTS .+ . Satisfactory LOD values by the FTIR-chemometric methods were achieved: 9.4 (mg/kg oil) for WC; 12.5 (mg gallic acid/kg oil) for TP, and 0.76 (mmol Trolox/kg oil) for ABTS .+ . The evaluation of the applicability of these analytical approaches was tested by use of validation sample sets (n = 16 for WC, n = 11 for TP and n = 14 for ABTS) with nearly quantitative recovery rates (99-114%). The FTIR-ATR method provided results that were comparable to conventional procedures. Practical applications: The presented method is based on ATR-FTIR in combination with multivariate calibration methodologies and permits a simultaneous evaluation of important quality parameters of VOO (WC, TP and ABTS .+ ). This approach represents an easy and convenient means for monitoring olive oil quality with the advantage of ease of operation, speed, no sample pretreatment and no consumption of solvents. The data obtained with this method are comparable to those obtained using the official reference method. Therefore, the technique is highly plausible as an alternative to the standard procedure for routine analysis or control at-line of production processes.