Refined Sunflower Oil Research Articles

Evaluation of oxidative stability of new cold-pressed sunflower oils during accelerated thermal stability tests

Refined sunflower oil has dissimilar shelf life compared to cold-pressed sunflower oil, which increases the use of refined oil, and it is more abundant in the diet. On the other hand, the production of cold-pressed oils does not require chemical processing. Moreover, these oils contain significant amounts of bioactive components with a beneficial health effect. Breeders are trying to create new sunflower hybrids for the production of cold-pressed oil with improved oxidative characteristics. This study aims to examine the rancidity of 24 cold-pressed sunflower oils of new hybrids under accelerated thermal stability test conditions (Rancimat and Schaal oven tests) and to compare the obtained results with refined sunflower oil. According to investigated oxidative parameters, the most similar to refined sunflower oil was the H20 sample with the induction period determined by the Rancimat test of 9.55 ± 0.00 h, compared to 9.49 ± 0.00 h, obtained in refined sunflower oil. The total oxidation value of the H20 sample amounted to 3.26 ± 0.12, while in refined sunflower oil this value was 2.12 ± 1.73.

Determination of the content of organic acids in the chemical composition of buckbuckthorn oil, obtained from regional raw materials

The purpose of the work is to determine the content of organic acids in the chemical composition of sea buckthorn oil obtained from regional raw materials and to establish the influence of sea buckthorn oil production technology on the content of biologically active substances. Sea buckthorn is a unique source product for enriching food products with biologically active substances that play a diverse, important role in the vital activity of the body. It has been proven that the content of organic acids and vitamin C is the main variable in the chemical components of sea buckthorn, the phytochemical and nutritional composition of whose berries differs significantly depending on the species, climatic and growing conditions, and the technology of obtaining sea buckthorn oil. This attracts attention from the standpoint of the need to study sea buckthorn, which grows in regional territories. It was established that sea buckthorn oil obtained from the juice contains: organic acids 154.1–167.5 mg%, vitamin C 168-214 mg%. Sea buckthorn oil extracted with refined sunflower oil contains: organic acids 234.5–388.6 mg%, vitamin C 189–243 mg%. The effect of the technology of obtaining sea buckthorn oil from regional raw materials on the content of biologically active substances, such as organic acids, vitamin C, was determined. Based on the results of research, the advantages of oil obtained by the technology of extraction with refined sunflower oil were determined. Such oil contains a larger amount of ascorbic acid and free organic acids. When analyzing the results of research on oil and dry raw materials collected in the Kherson region, it was established that in the case of organic acids, in particular vitamin C, the indicator of quantitative content is affected not only by the production technology, but also by the biological variety of sea buckthorn. It is advisable to intensively continue scientific work on the research of substances that are responsible for the specific biological activity of sea buckthorn oil.

Obtaining water-repellent coatings based on expanded perlite materials

Superhydrophobic coatings are currently not widely used due to complex scaling problems, high cost and low environmental resistance. One solution is the use of organic coating technology. The paper shows the possibility of obtaining surface coatings with high water-repellent properties based on expanded perlite and regenerated adsorbent. The most effective surface treatment is polymethylhydrogensiloxane. In the work properties of obtained coatings were characterized by contact angles using the sessile droplet technique, optical and electron microscopy and IR-spectroscopy. With polymer content is more than 50 wt% for untreated and more than 40 wt% for the polymethylhydrogensiloxane treated perlite, the Cassie steady state and the water contact angle of more than 140° were reached. The resulting coatings are an example of a good microscale base coat for the further creation of superhydrophobic volumetric hierarchical coatings. It has been shown that the use of an adsorbent for used refined sunflower oil is as effective as the use of freshly ground expanded perlite.

Impact of environmental stresses on the stability of acidic oil-in-water emulsions prepared with tofu whey concentrates

The emulsifying properties of tofu-whey concentrates (TWCs) at pH 3.0, 4.0, and 5.0, and the stability of the resultant oil-in-water emulsions against freeze-thawing (24 h, −20 °C) and controlled or mechanical stress (orbital stirring at 275 rpm, 40 min) were addressed. TWCs were prepared from tofu-whey by heating at 50 °C (8.0 kPa) or 80 °C (24.0 kPa), dialysis (4 °C, 48 h), and freeze-drying, giving the samples TWC50 and TWC80, respectively. The particle size and interfacial properties at the oil/water interface were measured. Emulsions were prepared by mixing the TWC aqueous dispersions (1.0% protein w/w) and refined sunflower oil (25.0% w/w) by high-speed and ultrasound homogenization. The preparation of TWCs at higher temperatures (80 °C) promoted the formation of species of larger particle size, a slight decrease of interfacial activity, and the adsorption of more rigid biopolymer structures associated with an increase of film viscoelasticity in interfacial rheology measurements. The emulsifying properties of both concentrates were enhanced with decreasing pH (5.0–3.0), through a significant decrease of particle size (D4,3) and flocculation degree (FD), but only those prepared with TWC80 exhibited higher stability to freeze-thawing and mechanical stress at pH 3.0. This could be ascribed to a combination of low initial D4,3 and FD values, high protein load, and the presence of rigid species that impart high viscoelasticity to the oil/water interface. These results would be of great importance for the utilization of TWCs as food emulsifiers in acidic systems to impart high stability to environmental stresses.

Нестаціонарний теплообмін у вертикальному циліндричному об’ємі, заповненому рідиною

The paper analyzes the conditions of convective heat transfer in the "limited volume" and in the "large volume". It is established that the process of heat exchange in the elements of the basic experimental setup in the system of experimental calculation method corresponds to heat exchange in a "large volume" under conditions of free convection. An experimental stand for the study of nonstationary heat exchange in the system "environment I ― body II", the main elements of which are two working cavities — the outer filled with water, volume V1, and the inner filled with the studied liquid medium volume V2, and V1 is larger V2 3 times. The results of experimental determination of heat transfer between the inner surface of a thin metal cylinder and the investigated liquid medium in a limited space for the system “environment I — body II” under the conditions of laminar regime of both the environment and the investigated liquid medium are presented. The heat transfer coefficient was investigated using the calculation-experimental method during heating and cooling of refined sunflower oil, distilled glycerin, sugar solution with a concentration of 50 %, 60 % under conditions of free convection. The experimental results are compared with the results of studies by well-known authors for "large volume" conditions. The conditions of the heat exchange process during the experiment at different directions of heat exchange in a "limited volume" (inside a thin-walled metal cylinder with the liquid under study) are described. It is substantiated that at the surface of a cylindrical metal wall in the process of heat exchange a thermal boundary layer is formed, within which the coolant temperature changes and heat transfer within the boundary layer occurs due to thermal conductivity. The criterion equations for determining the heat transfer coefficient during heating and cooling of the investigated liquid medium under free convection conditions are obtained.

Substantiation of technological parameters of the oil extract obtained from Urtica dioica roots based on the yield determination of phytosterols using capillary gas chromatography method

Due to the content of phytosterols, extractive preparations of Urtica dioica roots are able to show antiandrogenic effect in the case of external therapy of men and women with androgenic alopecia. Oil extracts (OE) are characterized by several advantages when applied to the skin of the scalp compared to water-alcohol extracts. For the development of OE technology from Urtica dioica roots, it is important to choose the optimal extraction parameters, which are based on the quantitative determination of phytosterols in the extractant and the studied samples of extracts.
 The aim of the work is to choose the optimal parameters for obtaining OE from Urtica dioica roots based on quantitative determination of phytosterols content in experimental samples of OE by gas capillary chromatography.
 Materials and methods. Objects of the research – Urtica dioica root, refined corn oil, refined sunflower oil, samples of oil extracts. Determination of phytosterol content in experimental samples was carried out by gas capillary chromatography (chromatograph “Crystal 2000”, manufacturer – research and production company “Analytics”).
 Results. 5 different compounds of steroid structure (stigmasterol, β-sitosterol, etc.) were identified in sunflower oil by gas liquid chromatography, and 10 (campesterol, 2-α stigmasterol, β-sitosterol, Δ5-avenosterol, etc.) were identified in sunflower oil. The quantitative content of β-sitosterol in the sum of sterols of corn oil was significantly higher compared to the content of this substance in sunflower oil and amounted to 59.33 %. Optimal technological parameters were established considering the peculiarities of extraction with oil extractant and quantitative determination of the amount of phytosterols and β-sitosterol in experimental samples of OE. The total content of plant sterols in OE, including considering their amount in the extractant, was in the range of 7880 mg/kg; the amount of β-sitosterol was 4638 mg/kg.
 Conclusion. The choice of optimal parameters for obtaining OE from UDR based on determination of phytosterol yield by gas capillary chromatography was experimentally substantiated, namely: extractant – corn oil, raw material-extract ratio – 1: 5, extraction time – 6 h, extraction method – maceration

Characterization of the Key Odorants Causing the Musty and Fusty/Muddy Sediment Off-Flavors in Olive Oils.

Microbial spoilage of olive fruits is among the most frequent reasons for two types of off-flavors in olive oils, assigned as musty and fusty/muddy sediment. To characterize both off-flavors on a molecular level by means of the sensomics approach, the key aroma compounds in a premium extra virgin olive oil (PreOO1) eliciting the typical sensory properties were compared to those identified in two off-flavor olive oils obtained from the International Olive Council (IOC). A comparative aroma extract dilution analysis (cAEDA) followed by identification experiments revealed 53 odorants in the musty reference olive oil (MusOO1) and 48 odorants in the fusty/muddy sediment one (FusOO1). Odorants, differing in flavor dilution (FD) factors or showing a high FD factor in at least one of the olive oils, were quantitated by stable isotope dilution analysis (SIDA), followed by the calculation of odor activity values (OAVs; ratio of concentration of an odorant to the respective odor threshold in odorless refined sunflower oil). Aroma recombination and omission experiments revealed 13 key aroma compounds in MusOO1 and 12 in FusOO1. To demonstrate the importance of volatile phenols, 10 phenolic smelling odorants were quantitated in further 13 extra virgin olive oils, in 3 musty and in 13 fusty/muddy sediment defective olive oils, and in 8 olive oils with other off-flavors. Both sensory defects could successfully be discriminated from extra virgin olive oils by applying either a principal component analysis or a hierarchical cluster analysis. Considering possible reaction pathways and all results obtained including Pearson coefficients between the odorant concentrations and the intensities of the defects, specifically 2-methoxyphenol and 4-ethylphenol were proposed as marker compounds for the quality assignment of both types of off-flavors induced by microbial spoilage among the identified key aroma compounds.

Transesterification of Refined Sunflower Oil to Biodiesel Using a CaO/ZSM‐5 Powder Catalyst

AbstractThe production of biodiesel from refined sunflower vegetable oil over basic CaO/ZSM‐5 catalysts was investigated. Several catalysts with various loadings of CaO on ZSM‐5 were prepared, calcined at 800 °C, and characterized by N2 adsorption‐desorption, X‐ray diffraction, Fourier transform infrared spectroscopy, and CO2‐temperature‐programmed desorption techniques. Calcined catalysts were tested in the transesterification reaction and reaction conditions were optimized by varying the catalyst‐to‐oil ratio and reaction time. The most active catalyst was the CaO/ZSM‐5 catalyst with a 35 wt % loading which gave the highest fatty acid methyl ester yield. The high catalytic activity was attributed to the active basic sites generated following CaO addition. Furthermore, the catalyst demonstrated stability against the leaching process.

Ways to improve the properties of natural wood when using waste vegetable oils

The article is devoted to the development and study of new compositions based on spent sunflower oil for the protective treatment of natural wood. Samples of birch and aspen wood were selected as the subjects of the study. The processing of wood samples was carried out by the method of “hot-cold impregnation”. Refined sunflower oil was used as the oil base of the propearized compounds developed. Plant oil fillers were chosen wood flour, stearic acid, canifol and sikkativ based on metal salts. The use of developed compounds can improve the hydrophobic properties of wood, increase its water and water resistance, as well as reduce swelling in tangential and radial directions. The optimal compositions on the basis of spent vegetable oil for protective processing of birch wood have been selected. The difference in the modifying capacity of the developed compositions for different types of wood is shown on the example of birch and aspen. Propiary compounds based on spent vegetable oil have environmental safety and their use allows the disposal of food waste.

Impact of lycopene and astaxanthin on hematological and immunological parameters of laying hens

The aim of this study was to determine the hematological profile and specific immunity of laying hens with the addition of oil extracts of lycopene or astaxanthin to the diet. The study used High Line W36 chickens that were vaccinated against Newcastle disease, infectious bronchitis, avian rhinotracheitis and egg drop syndrome. It was found that the addition of lycopene (20 mg/kg) and astaxanthin (10 mg/kg) for 30 days did not affect the hematological profile of laying hens. Increasing the content of lycopene to 40 and 60 mg/kg or astaxanthin to 20 or 30 mg/kg of feed for 30 days reduced the number of leukocytes and hemoglobin in the blood compared to the control, which received an equivalent amount of refined sunflower oil in the diet. Lycopene and astaxanthin supplements, regardless of dose and duration of administration, did not affect the titer of antibodies to Newcastle disease, infectious bronchitis, avian rhinotracheitis, and egg drop syndrome in serum of vaccinated laying hens. The obtained data can be used to justify the optimal dose and term of feeding of lycopene or astaxanthin supplements in the development of a model of carotenoid enrichment of chicken egg yolks.

Destruction of Biofilms on Silicone Tubes under the Action of a Mixture of Nocardia vaccinii IMV B-7405 Surfactants with other Biocides

The formation of pathogenic microorganisms biofilms on the central venous catheter is the cause of catheter-associated infections. An alternative method of combating biofilms is the use of “antibacterial” and “antifungal” locks, which are solutions of antibiotics or antifungal drugs in a mixture with other natural compounds, which can be microbial surface-active substances (surfactants) or essential oils. Aim. To investigate the role of Nocardia vaccinii IMV B-7405 surfactants mixture with other antimicrobial compounds in the destruction of biofilm on silicone tubes. Methods. N. vaccinii IMV B-7405 was grown in medium containing as carbon source purified glycerol and waste from biodiesel production, refined sunflower oil, oil after frying French-fried potatoes, Potato wedges and meat. The surfactants were extracted from supernatant of cultural liquid by modified Folch mixture. 2 mL of surfactant solutions, antifungal drugs (nystatin, fluconazole) or tea tree essential oil of the same concentration (5–640 μg/mL) were added to test tubes with silicone tubes (with pre-formed biofilm from test culture). To study the synergistic effect of the biofilms destruction, a mixture of surfactant solutions and antifungal substances (or essential oil) of the same concentration in a ratio of 1:1 (1 mL of each solution) was added to the test tubes. Sterile tap water (2 mL) was added to control test tubes instead of surfactants preparations, antifungal substances or essential oil. The degree of biofilm destruction (%) was determined as the difference between the adhesion of cells on the inner side of silicone tubes, untreated and treated with surfactants, antifungal drugs, essential oil, or their mixture. Results. It was found that surfactants synthesized by N. vaccinii IMV B-7405 on all substrates showed synergism of yeast and bacterial biofilms destruction on silicone tubes in a mixture with nystatin, fluconazole and tea essential oil in the whole range of investigated concentrations (5–640 μg/mL), but the highest effect was achieved at a concentration of 20–40 μg/mL. Thus, the degree of Candida albicans D-6, Candida utilis BVS-65 and Candida tropicalis PE-2 biofilms destruction under the action of a mixture of surfactants synthesized on waste from the biodiesel production and waste oil, with antifungal drugs was 45.8–71.8% and was higher than with only surfactants (21.2–41.6%), nystatin (22.4–24.1%) or fluconazole (28.1–31.3%). The destruction of Candida genus yeast biofilms under the action of surfactants synthesized on oil-containing substrates in a mixture with both nystatin and fluconazole reached 50.1–71.2%, which is 10–30% higher compared to the use of surfactants alone or only antifungal agents. The degree of Pseudomonas sp. MI-2, Escherichia coli IEM-1, Staphylococcus aureus BMS-1, Bacillus subtilis BT-2 (spores) biofilms destruction on silicone tubes treated with a mixture of tea tree essential oil and surfactants synthesized on all oil-containing substrates was 10–29% higher than in the case of using only solutions of surfactants (11.5–45.4%) or essential oil (21.4–34.5%) for the tubes treatment. Conclusions. The data obtained make it possible to consider surfactants synthesized by N. vaccinii IMV B-7405 on a wide range of cheap and accessible substrates as promising components of “antibacterial” and “antifungal” locks in combination with essential oils and antifungal agents.

The Role of Polydimethylsiloxane in Suppressing the Evolution of Lipid Oxidation Products in Thermo-Oxidised Sunflower Oil: Influence of Stirring Processes.

Suppressing the evolution of lipid oxidation products (LOPs) in commercially available culinary oils is considered to represent a valuable health-promoting incentive since these agents have cytotoxic and genotoxic properties and have been implicated in the pathogenesis of several chronic disease states. One agent used to suppress LOPs formation is polydimethylsiloxane (PDMS). In this study, proton nuclear magnetic resonance (1H NMR) analysis was employed to evaluating the influence of increasing PDMS concentrations (6.25 × 10−7, 1.0 × 10−5, 0.025, 0.05, 0.1, 0.5, 1.0, 5.0, and 10.0 ppm) in either stirred or unstirred refined sunflower oil exposed to thermal stressing episodes continuously at 180°C for 300 min with no oil replenishment. Results acquired showed that the extent of blockage of LOPs generation was correlated with increasing concentrations of PDMS. The minimal level of added PDMS required to provide a statistically significant protective role for both stirred and unstirred culinary oils when exposed to high frying temperatures was only 6.25 × 10−7 ppm. Furthermore, stirring at 250 rpm was experimentally determined to reduce the functional role PDMS. This is vital in a real world setting since the boiling process of frying may ultimately reduce the LOPs suppression activity of PDMS.

In-House Validation of an SPE-GC-FID Method for the Detection of Free and Esterified Hydroxylated Minor Compounds in Virgin Olive Oils.

Minor compounds in vegetable oils are distributed between free and esterified forms, and the ratio of these two fractions could represent an important parameter for assessment of oil authenticity. A simple method based on offline SPE-GC-FID for the analysis of free and esterified hydroxylated minor compounds in olive and sunflower oils has been developed and in-house validated. A satisfactory repeatability relative standard deviation (<7.5%) was obtained in all cases. The method, which requires simple instrumentation, allows for reliable quantification in a single chromatographic run with the advantages of minimizing sample manipulation, use of toxic solvents and reagents, and time consumption. The analytical procedure was applied to pure oil samples, including 15 authentic extra virgin olive oils collected from different European countries (Spain, Italy, Greece, and Portugal). Finally, the proposed SPE-GC-FID methodology could detect changes in the ratio between the free and esterified forms in pure extra virgin olive oil when mixed with refined sunflower oil at different percentages of 2, 5, 10, 15, and 20% (w/w) to simulate adulteration.

Fuel-grade sunflower oil butyl esters: synthesis, purification, oxidation stability

Current paper deals with production, purification and oxidative stability enhancement of fuel-grade sunflower oil butyl esters as more ecological alternative of methyl esters as biodiesel. The oil feedstock, used in this study, included refined sunflower oil (acid value – 0.05 mg KOH/g; 25.3 % of oleic and 61.2 % of linoleic acids) and wasted frying high-oleic sunflower oil (acid value – 1.20 mg KOH/g; 6.1 % of linoleic and 81.7 % of oleic acids). Butanolysis was carried out using potassium butoxide, obtained from KOH and alcohols via original patent-pending method, under mild reaction conditions (alcohol-to-oil molar ratio – 4.5-5.0, 15°C, 1.4-1.6 %еq. KOH of butoxide, 20-30 min). High molar yield of butyl esters (93-96 %) was achieved, while glycerol and vast majority of alkaline catalyst formed the separate reaction products phase mainly in the course of reaction. Ester enriched phases were purified in order to obtain fuel-grade butanol-based biodiesel. Samples after removing of butanol under vacuum followed by water washing and drying were characterized by not enough high butyl esters content (about 94-95 %), as well as higher than allowed content of unconverted glycerides. Vacuum distillation as final purification step allowed fitting butyl esters samples composition within the requirements for biodiesel fuel. Distilled samples contained about 99 % of butyl esters, 0.4-0.5 % of monoglycerides and almost no n-butanol, glycerol, di- and triglycerides. Oxidative treatment (110°C, 6 h, air bubbling) revealed the high oxidation stability of the sample, originated from wasted high-oleic oil, due to the predominance of oleic acid in its fatty acid composition. The sample, obtained from refined sunflower oil (mainly linoleic acid in fatty acid composition), demonstrated very low stability. Addition of at least 2000 mg/kg of antioxidant 2,6-di-tert-butyl-4-methylphenol was shown to be able to improve this characteristic to the level of biodiesel requirements.

The simple method of vegetable oils and oleochemical products acid value determination

Acid value is one of the key technical characteristic of vegetable oils and oleochemicals, obtaining on its basis. The existing standard methods of acid value measurement are relatively complicated and have some disadvantages. There are including utilization of the significant amounts of solvents, throwing out as wastes, and necessity in special equipment for determination. Also, a special issue is visual indication of the equivalence point of indicator transfer from acid to alkali form for intensive colored oils’ samples. Visual indication of the color transfer of phenol-phthalein as indicator (from colorless to pink) is quite difficult. The color transfer of thymolphthalein (from yellow to green) in such condition is not determined. Using of alkali blue 6B is complicated by the necessity of use ethanol and aromatic compounds mixture. In current work the rapid and simple method of acid value determination was proposed. It consists in alkali-acid titration of the sample by sodium butoxide solution in n-butanol with bromothymol blue, n-butanol is also using as solvent. The method was tested on 3 series of the mixtures of the refined sunflower oil and free fatty acids (distilled fatty acids of sunflower and rapeseed oils and chemical grade oleic acid). The fatty acid content in tested mixtures was in range 1-50 % wt. Some disadvantages of traditional methods, such as the necessity of mixed solvents’ and relatively complicated laboratory equipment use, titration in a hot state, effect of temperature changes in the laboratory and difficulties with visual indication of color transfer, were overcame. Proposed method requires only the simplest laboratory glassware (conic flasks, non-calibrated pipettes, hermetically sealed glass vessels for titrant) and technical laboratory scales (weighting accuracy ±0.01 g). The method allows to determine the acid value in wide range of samples, including the samples with intense coloration. The relatively high accuracy of acid value determination was shown. The method sensitivity is 0.02-0.10 mg KOH/g. The time for analyze is enough short (about 5-15 minutes).

Alkaline synthesis of fatty acids iso-propyl esters

Fatty acid alkyl esters are widely used products. Most of them are used as renewable transport fuel named “biodiesel”. Production of fatty acid iso-propyl esters mainly based on acid process, but using of alkaline catalysts may give good yields also. Alkaline catalysts have some advantageous such as low corrosivity and higher reaction rate. In current work the effectivity of potassium hydroxide and treated potassium hydroxide solution as catalyst for transesterification was compared. It was shown that using of KOH solution in iso-propyl alcohol after special treatment gives almost twice higher yields (95-96 %) from refined sunflower oil triglycerides than over KOH under the same conditions. Yield of fatty acids iso-propyl esters from wasted frying oil stabilized after 1-1.5 hours of reaction over both catalysts. Using 1.8 and 2.0 % treated catalyst at 90 °C leads to yield of about 86-88 % at 9:1 alcohol-to-oil ratio. Reaction temperature has significant impact on a yield wich decreases with temperature reduce in the range from 30 to 90 °C. During reaction proceeding the alkali saponification and thus loss the catalytic activity, which displayed in stopping the yield rising. The lower yield of esters from wasted oil comparing to the refined oil may be caused by presence of heavy polymerized triglycerides components formed during frying. Such components cannot be fully converted into monoalkylesters and gives also the oligomerized esters, which is not visible in standard gas chromatographic analysis of biodiesel. Indirect confirmation of the presence of such compounds in wasted frying oil sample is the sufficiently larger mass of the cube residue in vacuum distillation. For refined oil amount of such residue was only 5.4 %, while for wasted oil it was three time higher (14.9 %). In case of wasted frying oil as raw stuff, even after full conversion and effective self-separation conventional purification methods (like water washing or dry washing with adsorbents) may not provide the necessary purity of resulted biodiesel due to the presence of heavy oligomeric admixtures. In such cases vacuum distillation should be included as necessary final purification stage.

Evaluation of Biodiesel Produced from Blends of Sunflower Oil and Beef Tallow Through Base Catalysis

The inclination towards climate change and environmental pollution mitigation directs this research toward creating an alternative fuel source to fossil fuel for use in developing tropical countries. This study is designed to investigate biodiesel (alkyl esters) obtained by transesterification of blends of refined sunflower oil and beef tallow using NaOH as catalyst. Triglycerides in the oils reacted with alkanols to produce fatty acid alkyl esters (FAAE) and glyerols as by-product. A pretreatment process of esterification was carried out to remove excess free fatty acids (FFA). Some physical properties such as pour point, cloud point, flash point, density and kinematic viscosity were investigated for the sunflower oil/beef tallow (SO/BT) ratios. The examined physical properties of the methyl esters changed significantly as the beef tallow ratio in the mixture increased in the mixtures. The ratios of 40%SO/60%BT and 60%SO/40%BT exhibited values within standard range of biodiesel and petroleum diesel of ASTM D 6751 and EN 1424. The values of the cold-flow properties of the biodiesel ratios obtained are of convenience for use in tropical regions rather than polar regions.

Determination of the fatty acids composition of refined sunflower oil and possibility of its changing during storage period

Refined sunflower oil is an auxiliary component of many dosage forms made in pharmacy. For their preparation, pharmacies purchase oils from different manufacturers and have the right to use it throughout the shelf life. However, the question arises of maintaining the stability of the fatty acid composition of the oil because of the influence of various environmental factors. In previous studies, the authors investigated the change in the composition of basic fatty acids (FA) of sunflower oil during heating or long-term storage, but there are no studies of the full FA composition of sunflower oil, as well as an assessment of its dependence on the period of the oil using. The aim. Detailed study of the FA composition of refined sunflower oil from different manufacturers, assessment of the effect of the shelf life of the oil on its FA composition and its compliance with the requirements of the European Pharmacopoeia (EP). Materials and methods. The determination of the FA composition of seven samples of refined sunflower oil was carried out by gas chromatography with a flame ionization detector using the Rt-2560 column (100 m×0.25 mm×0.20 µm). Results. The analysis of seven samples of refined sunflower oil showed the presence of 24 FA in most of them. Polyunsaturated FA predominate among them with a percentage of 52.45-60.86 %. The value of the fatty acids percentage in each groups (saturated, mono- and polyunsaturated fatty acids) are quite similar regardless of the oil shelf life at the time of the research. All test samples, except one, by the percentage content of the main FA correspond to EP requirements. The results of the quantitative content of the main FA of sunflower oil determining (palmitic, stearic, oleic, and linoleic) also indicate a similar FA composition of the studied samples. Conclusions. The studied samples of sunflower oil refined in terms of the content of basic FAs meet the requirements of the EP. The obtained results indicate the high stability of the oil and the absence of a significant effect of the storage period on the FA composition.

Electrophysical methods for controlling the quality of vegetable oil in a digital economy

The article considers the possibility of controlling the quality of vegetable oil by electrophysical methods. In model experiments, refined sunflower oil sold in retail was selected as objects of research. During model studies, samples of vegetable oil were oxidized in air at a temperature of 120°C until the values of peroxide value (PV) were close to the maximum allowable 10 μग kg−1. The dependence, allowing evaluating the effect of the polar products of vegetable oil oxidation on the change in the coordinates of the identification point, was determined by the results of these studies. When developing operational control of the degree of purification of vegetable oil at the stages of refining, samples were studied under industrial conditions. In each sample, the values of acid and peroxide values were determined, as well as the coordinates of the identification point. The technical result of these studies is the development of a single operational digital method to establish the degree of purification of vegetable oils with the requirements of current regulatory documentation at the stages of refining.

Vehicle Emission Analysis by using Refined Sunflower Oil as Alternate Fuel and Varying the Injection Timing in Diesel Engine

In this study, the emissions of Kirloskar Direct Injection 4-stroke Diesel engine, single cylinder air cooled, 4.4 kW, constant speed at 1500 rpm, compression ratio 17.5:1 with different blends of diesel refined sunflower oil is analysed. Methyl Esters of refined sunflower was trans-esterified before blending with diesel. The main objective of this experiment is to study the NOx, CO, HC and smoke emissions by varying the injection timing and load. The experiments were conducted with various blends - BRSF10, BRSF30, BRSF40, at different pressures (180 bar, 210 bar, and 240 bar) and different level of loads (0%, 25%, 50%, 75%, 100%). A 3-hole nozzle was used to inject the fuel. The combustion results were studied using AVL gas analyser. The results show that engine temperature decreases at higher loads by 2°, NOx and CO decreases and there was a marginal increase in HC and the exhaust temperature.