Oxidation Of Sunflower Oil Research Articles

Antioxidant activity evaluation of the combination of oregano (Origanum vulgare) and laurel (Laurus nobilis) essential oil as two natural “chain-breaking” antioxidants by direct measurement of sunflower oil oxidation

Antioxidants are commonly used to reduce oxidative damage in lipids, and essential oils offer natural alternatives with antioxidant properties. This research seeks to determine the antioxidant efficiency of the combination of laurel (laurus nobilis) and oregano (origanum vulgare) essential oils exhibiting a chain-breaking mechanism. To this end, an accelerated oxidation of sunflower vegetable oil was carried out at 60 °C for 28 days, in combination with concentrations of 0.05% w/w (1) and 0.02% w/w (2) of the essential oils. BHT at 0.02% w/w was used as a reference antioxidant. The chemical indicators of oxidation (dienes conjugated, peroxides, anisidine and TOTOX values) and volatiles (2-heptenal Z, 2,4-Decadienal EZ and EE) were determined. While no substantial differences were found between the studied concentrations of the essential oils, a decrease in the protective effect was observed when the concentration of laurel was increased. Interestingly, the antioxidant effect of both oregano and laurel essential oils was observed to be similar to that of BHT. The results suggest that the combination of these essential oils with chain-breaking antioxidant mechanisms might be used as an antioxidant in food.

Determination the influence of the synthetic antioxidants mixture on the oxidative stability of sunflower oil

The object of the study is the process of sunflower oil oxidation under conditions of increased temperature. Sunflower oil is one of the most common oils and is used in the chemical, food and other industries. The main type of oil spoilage is oxidation, which is accelerated under the influence of radiation, elevated temperatures, long-term storage with oxygen access. Oxidation products prevent the effective use of oil in chemical reactions and technological processes. An important task is to develop and improve methods for increasing the oxidative stability of sunflower oil using antioxidants. The oxidation process of refined deodorized frozen sunflower oil according to DSTU 4492 (CAS Number 8001-21-6) was studied by the method of differential scanning calorimetry. The simultaneous effect of synthetic antioxidants (tert-butylhydroquinone, butylhydroxyanisole, butylhydroxytoluene) in different ratios on the oil induction period at a temperature of 110 °C was determined. The total concentration of the antioxidant mixture in each experiment was 0.02 %. The initial oil induction period is 270.61 min. Rational ratios of antioxidants were determined: tert-butylhydroquinone: butylhydroxyanisole: butylhydroxytoluene (16.67:66.67:16.67) %; tert-butylhydroquinone: butylhydroxyanisole: butylhydroxytoluene (33.33:33.33:33.33) %. The corresponding oil induction periods were 382.56 min. and 385.87 min. The effect of citric acid (0.005 %) and defoamer (polydimethylsiloxane, 0.0002 %)) on the induction period of oil with the addition of antioxidant mixtures was determined. The corresponding oil induction periods were 420.78 min. and 430.25 min. The results of the study make it possible to increase the oxidative stability of sunflower oil, which will contribute to the effective use of oil in various areas

Advances in the Use of Four Synthetic Antioxidants as Food Additives for Enhancing the Oxidative Stability of Refined Sunflower Oil (Helianthus annuus L.)

The present investigation was performed to evaluate the effects of various synthetic antioxidants (vitamin A, vitamin E, β-carotene, and BHT) on the oxidation of sunflower oil subjected to accelerated thermal storage at 60 °C for three months (12 weeks). The performance of the antioxidants studied was evaluated using several quality parameters: the free fatty acid value (FFA), primary oxidation (via the peroxide value (PV) and K232 value), secondary oxidation products (via the anisidine value (p-AV) and K270 value), and the total oxidation value (TOTOX). The fatty acid composition (FAC), oxidizability value (COX), iodine value (IV), and pigment content (chlorophyll and carotenoid) were also evaluated. The results revealed that the control sample of sunflower oil exhibited higher susceptibility to oxidative deterioration. Antioxidants at 200 ppm were more effective in preserving the oxidative stability of sunflower oil subjected to accelerated storage compared to the control oil. The smallest increases in all stability parameter indexes were recorded for antioxidant-supplemented sunflower oil. However, the IV and chlorophyll and carotenoid contents were reduced. At 200 ppm, vitamin E and β-carotene showed the greatest stability in sunflower oil, while their combination with vitamin A at 100 ppm of each showed the lowest stability. In addition, synthetic antioxidants provided greater protection against the degradation of polyunsaturated fatty acids (PUFAs). The highest level of PUFA degradation was recorded in the control oil, followed by the oil containing vitamin A. In conclusion, adding synthetic antioxidants to sunflower oil improves its stability during storage. However, some authors associated these molecules with a health risk due to carcinogenic effects as these molecules have been listed as “Generally Recognized As Safe” (GRAS).

Antioxidant and antimicrobial extracts from grape stalks obtained with subcritical water. Potential use in active food packaging development

In order to valorise winemaking grape stalks, subcritical water extraction at 160 and 180 °C has been carried out to obtain phenolic-rich extracts useful for developing active food packaging materials. Red (R) and white (W) varieties (from Requena, Spain) were used, and thus, four kinds of extracts were obtained. These were characterised as to their composition, thermal stability and antioxidant and antibacterial activity. The extracts were incorporated at 6 wt% into polylactic acid (PLA) films and their effect on the optical and barrier properties of the films and their protective effect against sunflower oil oxidation was analysed. Carbohydrates were the major compounds (25–38%) in the extracts that contained 3.5–6.6% of phenolic compounds, the R extracts being the richest, with higher radical scavenging capacity. Every extract exhibited antibacterial effect against Escherichia coli and Listeria innocua, while PLA films with extracts preserved sunflower oil against oxidation.

Determination of the effect of bitter gourd (Momordica charantia L.) seed oil on the oxidative stability of sunflower oil

Abstract The effects of bitter gourd seed oil (Momordica charantia) the storage stability of sunflower oil were examined in the present study. The effects of oxidation and those of the bitter gourd addition on the quality characteristics of the sunflower oils were determined by using classical and spectrophotometric methods during thermal oxidation. The changes of sunflower oil samples added with different concentrations (10 and 20 %) of bitter gourd seed oil were found in Raman and Fourier transform infrared spectroscopy and it was also observed that there was an increase due to secondary oxidation products forming during the storage. Furthermore, the oxidation of sunflower oils was comparatively examined by using nuclear magnetic resonance spectroscopy. As a result of both classical and spectrophotometric analyses, it was determined that the addition of 10 % bitter gourd seed oil enhanced the storage stability of sunflower oil.

Retarding sunflower oil oxidation during the deep-fat frying of potato chips using micro-encapsulated Convolvulus arvensis Linn leaf phenolic extract

In this research, the extraction of polyphenols from Convolvulus arvensis (CA) leaves was optimized using ethanol (80%) at plant/solvent ratios and extraction times which varied between 1/10 to 1/30 (w/v) and 20 to 120 min, respectively. The extract with the highest polyphenol content was obtained at a ratio of 1/30 and 90 min. At 120 ppm, the preceding extract in either lyophilized (LyCAE) or encapsulated (EnCAE) form was evaluated as an antioxidant during the frying process using sunflower oil in comparison to TBHQ. Frying oil quality indices including refractive index, smoke point, acid value, anisidine value, polar and polymer compounds were monitored throughout frying times. FTIR spectroscopy was used to investigate the changes in trans-fatty acids, hydroperoxides and aldehyde contents. The results showed that the phenolic extract, especially in EnCAE form, exhibited superior antioxidant activity over TBHQ, which consequently led to the utilization of this phenolic extract as an antioxidant in frying oils.

OBTAINING ANTIOXIDANTS FROM FOOD INDUSTRY WASTE AND THEIR USE IN FATS

The food industry generates a large amount of waste and by-products of processing, which becomes a problem for the environment. Potato and onion peel, tomato seeds and peel are agro-industrial wastes of the world's main vegetable crops. However, the potential for antioxidants from them is not yet fully known. In this work, the influence of extracts obtained from these wastes on the process of inhibition of the rate of oxidation of sunflower oil was studied. Regression equations describing the process of extraction of biologically active substances from crop production waste as a result of water-ethanol extraction at a temperature of 60°C were obtained. It was established that the optimum concentration of ethanol in the water-ethanol mixture of extractants is in the range of 70–80%. Increasing the extraction time has a positive effect on the yield of extractive substances (at an interval of 2–15 hours). The kinetics of oxidation of sunflower oil by the accelerated method was studied and the antioxidant activity of the obtained antioxidants was determined, which is: for onion peel 2.29 (ie at a concentration of antioxidant 200 mg/kg oil the induction period of sunflower oil oxidation is more than doubled). For potato peels, this figure is 3.17, and for tomato peels – 1.85. All antioxidants obtained from plant waste were no less effective than butylhydroxyanisole (antioxidant activity – 1.93). The effectiveness of antioxidants varied as follows: onion peel > potato peel > butylhydroxyanisole > tomato residues. The expediency of using ascorbic acid in the course of water-alcohol extraction of antioxidants from vegetable raw materials has been proven. It has a positive effect on increasing the output of antioxidants and on extending the induction period of sunflower oil as a result of its own antioxidant properties. The existence of a synergistic effect between ascorbic acid and substances extracted from potato, onion and tomato peel has been proven, which in numerical value is 163, 126, and 180%, respectively.

Optimization of ultrasound- and enzymatic-assisted extractions of polyphenols from dried red onion peels and evaluation of their antioxidant activities

There is a recognized need for exploring new natural antioxidants that have high antioxidant potential. Thus, the aim of this study was to optimize the extraction process of onion peels using ultrasound- and enzymatic-assisted extractions (UAE and EAE) methods to utilize the optimal extracts as natural antioxidants. Box–Behnken Design (BBD) was implemented to reach the optimal extracts with the highest simultaneous content of total phenolic content (TPC) and total flavonoid content (TFC). The optimal UAE and EAE extracts were subjected to High Performance Liquid Chromatography (HPLC) analysis to identify their chemical profile. The antioxidant activities of optimal extracts obtained by UAE and EAE were evaluated in vitro using DPPH and FRAP assays and their abilities to increase the oxidative stability of sunflower oil were studied using Rancimat test. The optimal conditions for UAE were 34.02 W, 26.87 mL/g solid, and 45.43 min, meanwhile they were 30.00 mL/g solid, 45.43 min at enzyme concentration of 0.52% for EAE method. DPPH and FRAP assays results revealed that EAE optimal extract show superior antioxidant activity over UAE optimal extract. The protection factor of optimal EAE extract against sunflower oil oxidation was close to that of butylated hydroxytoluene (BHT).

Stabilization of Sunflower Oil with Biologically Active Compounds from Berries.

Sunflower oil (Helianthus annuus) contains a rich concentration of polyunsaturated fatty acids, which are susceptible to rapid oxidative processes. The aim of this study was to evaluate the stabilizing effect of lipophilic extracts from two types of berries, sea buckthorn and rose hips, on sunflower oil. This research included the analysis of sunflower oil oxidation products and mechanisms, including the determination of chemical changes occurring in the lipid oxidation process via LC-MS/MS using electrospray ionization in negative and positive mode. Pentanal, hexanal, heptanal, octanal, and nonanal were identified as key compounds formed during oxidation. The individual profiles of the carotenoids from sea buckthorn berries were determined using RP-HPLC. The influence of the carotenoid extraction parameters ascertained from the berries on the oxidative stability of sunflower oil was analyzed. The dynamics of the accumulation of the primary and secondary products of lipid oxidation and the variation of the carotenoid pigment content in the lipophilic extracts of sea buckthorn and rose hips during storage demonstrated good stability at 4 °C in the absence of light for 12 months. The experimental results were applied to mathematical modeling using fuzzy sets and mutual information analysis, which allowed for the prediction of the oxidation of sunflower oil.

Assessing the pharmacologicaland biochemical effects of Salvia hispanica (Chia seed) against oxidized Helianthus annuus (sunflower) oil in selected animals.

Oil oxidation is important in terms of taste, nutritive component quality and toxic effect of the oil. In this study, the oxidized sunflower oil was used along with chia seed in rabbits for the determination of its effects on various hematological and serum biochemical parameters as well as on liver histopathology. Three rabbits were fed with oxidized oil (obtained by heating) at the dose rate of 2 ml/kg body weight by mixing it with green fodder. The other rabbit groups were fed with Chia seed at dose rate of 1, 2 and 3 g/kg along with oxidized sunflower oil. Chia seed was fed alone to three rabbits at the dose rate of 2 g/kg body weight. All rabbits were fed regularly for twenty-one days. For the determination of hematological and biochemical parameters, whole blood and serum samples were collected on different days during feeding period. For histopathology, liver samples were used. Significant changes (p<0.05) were noted in the hematology and biochemical indices in the rabbits that were fed with oxidized sunflower oil alone, and along with different doses of Chia seed. In a dose-dependent manner, all these parameters were significantly improved (p<0.05), when the amount of Chia seed was increased. The biochemical and hematological indices were in normal range in the group fed only with Chia seed. In oxidized oil fed group, liver histopathological analysis showed that cholestasis was present at both sides (bile pigment secretion) and zone 3 necrosis with mild inflammatory cells. Mild vacuolization of hepatocytes was also observed. In Chia seed fed group, hepatocyte vacuolization and mild necrosis was noted. It was concluded that oxidized sunflower oil alters the biochemical and hematological parameters and causes liver abnormalities. Chia seeds act as an antioxidant and retrieve those alterations.

Lid Films of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/Microfibrillated Cellulose Composites for Fatty Food Preservation.

The present work evaluates the food packaging performance of previously developed films of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) reinforced with atomized microfibrillated cellulose (MFC) compatibilized by a reactive melt-mixing process. To this end, the novel green composite films were originally applied herein as lids in aluminum trays to preserve two dissimilar types of fatty foods, namely minced pork meat and sunflower oil. Results indicated that the PHBV/MFC films effectively preserved the physicochemical and microbiological quality of pork meat for one week of storage at 5 °C. In particular, the compatibilized green composite lid film yielded the lowest weight loss and highest oxidative stability, showing values of 0.935% and 0.78 malonaldehyde (MDA)/kg. Moreover, none of the packaged meat samples exceeded the acceptable Total Aerobial Count (TAC) level of 5 logs colony-forming units (CFU)/g due to the improved barrier properties of the lids. Furthermore, the green composite films successfully prevented sunflower oil oxidation in accelerated oxidative storage conditions for 21 days. Similarly, the compatibilized PHBV/MFC lid film led to the lowest peroxide value (PV) and conjugated diene and triene contents, with respective values of 19.5 meq O2/kg and 2.50 and 1.44 g/100 mL. Finally, the migration of the newly developed PHBV-based films was assessed using two food simulants, proving to be safe since their overall migration levels were in the 1-3 mg/dm2 range and, thus, below the maximum level established by legislation.

Potential of indigenous plants seed extracts of Anisophyllea boehmii and Aframomum sanguineum from Burundi to protect against oil oxidation.

The objective of seed extracts from Anisophyllea boehmii and Aframomum sanguineum were to evaluate their ability to stabilize against oxidation of oils exposed to sunlight on one hand and subjected to high temperatures on the other hand. Determination of the peroxide value (PV) showed that the extracts had reduced the oxidation of sunflower oils. After 8 weeks of sunlight exposure, the concentration of 265.45 mg/l of A. boehmii extract showed a PV of 30.78 meq O2/kg, 67.4 mg/l extract of A. sanguineum had a PV of 42.75 meq O2/kg while the oils without extracts had a very high PV (125.06 meq O2/kg). Heating of the oils to 180°C for 8 hours was found, with A. boehmii extract (265.45 mg/l), to have a PV of 29.66 meq O2/kg, with that of A. sanguineum, while the PV of the oils without extract reached 50.66 meq O2/kg. In the light of these results, the seeds of A. boehmii and A. sanguineum contain antioxydant compounds, which, once extracted, can be used for many purposes in the food processing, pharmaceutical and cosmetic industries.

Thermally oxidized sunflower oil diet alters leptin/ghrelin balance and lipid profile in rats: Possible role of reactive aldehydes in dyslipidemia.

Sunflower oil is a common edible oil in the world, which is highly prone to oxidative degradation during the frying process. The present study aimed to investigate the effects of products obtained from the thermal oxidation process of sunflower oil on metabolic indices, and the secretion status of leptin and ghrelin in rats. In vivo studies were designed after determining the rate of formation of active aldehydes and peroxide value in sunflower oil following 300°C in a period of 30-240 min. To this end, 36 rats in 6 separate groups were fed with 2ml of normal saline, fresh sunflower oil, and heated oils at 30, 60, 120, and 240 min for 45 days. Finally, lipid profile changes and leptin/ghrelin secretion were examined, along with histological changes in the liver tissue. The results indicated a significant increase in serum LDL, VLDL and triglycerides, and a decrease in HDL, in the groups treated with heated oils. These changes were associated with a higher accumulation of triglycerides, active aldehydes, and histological changes in the hepatic tissue. Although the serum ghrelin level in the groups receiving heated oil did not change significantly compared to the fresh oil, the serum leptin level increased significantly in the groups receiving heated oil. According to our findings, increasing the time of sunflower oil heating enhanced the formation of active aldehydes, so that daily consumption of such oxidized oils might be associated with the occurrence of dyslipidemia, fatty liver and the development of leptin resistance. PRACTICAL APPLICATIONS: Sunflower oil is highly prone to oxidative degradation during the frying process. Increasing time of sunflower oil heating enhanced the formation of active aldehydes. Daily consumption of oxidized oils might be associated with the occurrence of dyslipidemia, fatty liver and the development of leptin resistance.

Effect of microwave pretreatment of sunflower kernels on the aroma-active composition, sensory quality, lipid oxidation, tocopherols, heterocyclic amines and polycyclic aromatic hydrocarbons of sunflower oil

The application of microwaves on sunflower kernels, as a new flavour generation technique, to produce sunflower oil was investigated. Using solvent-assisted flavour evaporation (SAFE), HS-SPME and GC-O-MS, 75 odourants were identified in sunflower oils, where 44 were newly found. With the increasing microwave time, aroma-active terpenes decreased from 74 to 33 mg/kg, aroma-active heterocyclics increased from 0 to 196 mg/kg, and aroma-active carbonyls increased from 2 to 28 mg/kg in sunflower oils (p < 0.05). Meanwhile, the perceived intensities of roasted and smoky aromas enhanced, while the intensities of raw sunflower seed and woody aromas decreased in sunflower oils (p < 0.05). Microwaves did not cause surface rupture but increased the interior porosity of sunflower kernel. The tocopherol loss in sunflower oils was less than 7.2% and the oil yield increased from 19.45% to 35.10% after microwaves. The temperature rise by microwaves was responsible for the gradually decreased protein solubility and increased HCAs (7.3–820.6 ng/g) and PAHs (7.78–109.76 ng/g) in oils. Microwave technology, when being applied at appropriate power and duration, is promising for producing sunflower oil, however, process temperature needs to be controlled to balance between sufficient flavour formation and denaturation of protein as the by-product.

Individual and Joint Effect of Alpha-Tocopherol and Hydroxytyrosol Acetate on the Oxidation of Sunflower Oil Submitted to Oxidative Conditions: A Study by Proton Nuclear Magnetic Resonance.

This study tackles the individual and joint effect of alpha-tocopherol and hydroxytyrosol acetate on the oxidation of sunflower oil submitted to accelerated storage conditions at intermediate temperature, in order to deepen the understanding of antioxidant–prooxidant behaviour. This was accomplished by 1H Nuclear Magnetic Resonance. For this purpose, the evolution of the degradation of both the main components of the oil and the aforementioned added compounds was monitored by this technique throughout the storage time. Furthermore, the formation of a very large number of oxylipins and the evolution of their concentration up to a very advanced stage of oil oxidation, as well as the occurrence of lipolysis, were also simultaneously studied. The results obtained show very clearly and thoroughly that in the oxidation process of the oil enriched in binary mixtures, interactions occur between alpha-tocopherol and hydroxytyrosol acetate that notably reduce the antioxidant effect of the latter compound with the corresponding negative consequences that this entails. The methodology used here has proved to be very efficient to evaluate the antioxidant power of mixtures of compounds.

Effect of beeswax and combinations of its fractions on the oxidative stability of oleogels

Beeswax can be a good structuring agent for edible oleogels. There is controversy about its role in the oleogel oxidation processes. This study investigated the oxidative stability of oleogels and the impact of their composition and texture on this stability. Oleogels were created by structuring sunflower oil with beeswax or combinations of its fractions (6% w/w gelator). Preparative flash chromatography was used to obtain beeswax fractions, which had a diverse composition according to TLC and HPLS-ELSD (hydrocarbons, wax esters, free fatty acids, and alcohols). Different oxidation indices (PV, AV, CDV, TOTOX, volatile organic compounds) of oleogels were evaluated, as well as their textural properties (firmness and Young's modulus) after 20 days of storage at 35 °C. Among the tested samples, unstructured sunflower oil demonstrated the highest oxidative stability. The sample based on hydrocarbons and monoesters was the most stable of the oleogels tested. Hexanal is the most common volatile organic molecule generated during the oxidation of sunflower oil. Oleogels have a more complex profile of volatile compounds, including ketones, alcohols, and terpenes. Beeswax based oleogel's induction period was the shortest. The oxidation rate of oleogels and Young's modulus (r2 = 0.9511, negative), as well as the concentration of free fatty acids (r2 = 0.8195, positive) had a strong correlations. The results show that oleogels structured with beeswax fractions could be beneficial in fat-containing products with improved oxidation resistance.

Immunomodulatory effect and histological alteration of thermally oxidized sunflower oil in male Wistar rats

Many foods are prepared by deep-frying as this provides unique flavors/textures that improve overall palatability to consumers. Sunflower oil is one of the most widely-used frying oils in the world. However, during frying, fats in the foodstuff are heated to &gt; 150° C and concurrently come into contact with agents found in the air, water, and other foods being cooked at the same time. Since long-term consumption of oxidized/oxidation products can contribute to the development of a variety of pathologies. Used cooking oil has become of increased concern to both health administrators and consumers. Few studies have sought to examine potential immunomodulatory effects from exposures to sunflower oil or its oxidized/oxidation products. To address this gap in knowledge, here, sunflower oil was used to fry potatoes at 190° C, every 30 min; a new 100 g batch of slices was cooked. Frying was performed continuously for 5h/day for 2 and 4 days (10 and 20 h total), and then the parental uncooked oil and each of the used oils were provided to Wistar rats in their diet (at 20% level) for a total of 10 weeks. Measures of body weight\food intake indicated that diets containing the used oils led to slightly reduced food intakes and host weights. Kidney weights were not affected by consumption of the two used oils, but the liver was enlarged in rats fed with the oil treated for 20 h. Evaluation of key lipid-serum parameters, i.e., total cholesterol, HDL cholesterol, and triglycerides, revealed a diet-related decrease in each; oxidized fats reduce their concentration compared to fresh fats. Conversely, serum LDL cholesterol levels were increased. Histological analyses indicated that consumption of the oxidized oils caused both kidney (e.g., tubular/glomerular dilation, vascular congestion, inflammation, tubular necrosis) and liver (e.g., vascular congestion, inflammation, necrosis) damages. Assessments of host immune function, i.e., ability to form antibody to ovalbumin (OVA) challenge, indicated that in rats fed the used oil, there were significant decreases in serum anti-OVA antibody levels. This suggested that host immunocompetence could be compromised as a result of long-term consumption of a diet containing a relatively high (i.e., 20%) content of used sunflower oils.

Recombination of oxidized samples of DHA and purified sunflower oil reproduces the odor profile of impaired algae oil from Schizochytrium sp. and reveals the odor contribution of fatty acids other than DHA

Algae oil from Schizochytrium sp. is one of the major natural sources of ω-3 polyunsaturated fatty acids (PUFAs), but its applications in foods are limited because of its unpleasant odor. The complex composition of algae oil originates an odor profile that differs from that of its major PUFA, i.e. docosahexaenoic acid (DHA). The aim of this work was to explore the specific role of DHA oxidation in the odor profile of algae oil. According to the fatty acid composition and odor characteristics, oxidized sunflower oil was selected and combined with oxidized DHA to simulate the odor profile of algae oil. The recombination oil showed similar odor characteristics to the algae oil sample indicating that DHA oxidation was key in the formation of the unpleasant odor in algae oil and that oxidation of fatty acids other than DHA also made a contribution. The constructed off-flavor of algae oil was a consequence of a synthetic effect between odorants from oxidized DHA and oxidized oleic, linoleic and linolenic acid. This study provided a reference for the source research of volatile substances producing fishy odor in algae oil.

Dejstvo ekstrakta đumbira (Zingiber officinale) kao prirodnog antioksidansa na smanjenje oksidacionih promena suncokretovog ulja

Oil oxidation is significant for acceptability, nutritional quality, and toxicity of edible oils. Antioxidant supplementation for oil is a common and fundamental strategy for improving its oxidative stability and prolonging induction time. Ginger contains natural antioxidants such as phenolic and flavonoid compounds. Ginger extracts were prepared by extraction with different solvents (methanol, ethanol, acetone and water). Ethanolic ginger extract had the highest yield (10.52%), whereas the aqueous extract had the lowest yield (8.10%). Also, the ethanolic extract was the highest in the content of phenolic and flavonoid compounds (75.17 and 19.55 mg/g, respectively), followed by methanolic extract (67.24 and 17.46 mg/g, respectively). Thus, further elaboration focused on the ethanolic extract. The scavenging ability of ginger extract was dose-dependent; it increased with the increase in ginger extract concentration. As expected, the ginger extract had lower DPPH scavenging activity than BHT (synthetic antioxidant). Free fatty acid (FFA), peroxide value (PV), conjugated dienes (CD) and thiobarbituric acid (TBA) value were used to evaluate the effect of ginger extract as a natural antioxidant on sunflower oil oxidation. The higher the concentration of ginger extract, the lower the magnitude of FFA, PV, CD, and TBA in sunflower oil. According to our findings, the level of sunflower oil supplementation with ginger extract should be below 600 mg/kg. The result of this study suggests that ginger extract can be recommended as a natural antioxidant to retard sunflower oil oxidation.

Dejstvo ekstrakta đumbira (Zingiber officinale) kao prirodnog antioksidansa na smanjenje oksidacionih promena suncokretovog ulja

Oil oxidation is significant for acceptability, nutritional quality, and toxicity of edible oils. Antioxidant supplementation for oil is a common and fundamental strategy for improving its oxidative stability and prolonging induction time. Ginger contains natural antioxidants such as phenolic and flavonoid compounds. Ginger extracts were prepared by extraction with different solvents (methanol, ethanol, acetone and water). Ethanolic ginger extract had the highest yield (10.52%), whereas the aqueous extract had the lowest yield (8.10%). Also, the ethanolic extract was the highest in the content of phenolic and flavonoid compounds (75.17 and 19.55 mg/g, respectively), followed by methanolic extract (67.24 and 17.46 mg/g, respectively). Thus, further elaboration focused on the ethanolic extract. The scavenging ability of ginger extract was dose-dependent; it increased with the increase in ginger extract concentration. As expected, the ginger extract had lower DPPH scavenging activity than BHT (synthetic antioxidant). Free fatty acid (FFA), peroxide value (PV), conjugated dienes (CD) and thiobarbituric acid (TBA) value were used to evaluate the effect of ginger extract as a natural antioxidant on sunflower oil oxidation. The higher the concentration of ginger extract, the lower the magnitude of FFA, PV, CD, and TBA in sunflower oil. According to our findings, the level of sunflower oil supplementation with ginger extract should be below 600 mg/kg. The result of this study suggests that ginger extract can be recommended as a natural antioxidant to retard sunflower oil oxidation.