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Öğe Acidic and enzymatic pre-treatment effects on cold-pressed pumpkin, terebinth and flaxseed oils(Consejo Superior Investigaciones Cientificas-Csic, 2022) Ozkilic, S. Y.; Arslan, D.Oil yield and the properties of oil can be improved with various enzymatic pre-treatments before obtaining oil from oilseeds by cold-press extraction. A commercial mixture of pectolytic enzymes was used in this study. In addition, apple seed meal as a source of beta-glucosidase enzyme and citric acid were applied to oilseeds (pumpkin, terebinth and flaxseed) as pre-treatments. The results were evaluated by comparing the effects of the pre-treatments on oil yield and properties. Enzyme preparate could increase the oil yield of pumpkin seeds (similar to 300%) and flaxseed (151%). Significant increases in the phenolic contents of terebinth (from 91.67 to 319.33 mg GAE/kg) and flaxseed oils (from 12.03 to 40.47 mg GAE/kg) were achieved by citric acid and enzymatic pre-treatments. These two pre-treatments were also effective in terms of peroxide formation and oxidative stability in terebinth oil. With the help of the pre-treatments applied to oilseeds it was possible to increase the transition of phenolics from seeds to oil for terebinth oil with increase ratios of 245% for citric acid, 248% for the enzymatic process compared to the control.Öğe Changes in chemical composition of some oils extracted from seeds roasted at different temperatures(Wageningen Academic Publishers, 2015) Simsek, E.; Ozcan, M. M.; Arslan, D.; Unver, A.; Kanbur, G.Oil seeds are commonly used in cooking, frying and as salad oil and have commercial and economic importance. Since the seeds are roasted before pressing of the oil, changes occur in their composition; thus it is crucial to modify roasting process to minimise adverse effects. This study reflects the effects of different roasting temperatures (90, 150 and 210 degrees C for 10 min. in conventional oven) on the oil constituents and some chemical properties of oils from the seeds of sesame, sunflower, soybean, flaxseed and poppy along with comparison to those of unroasted corresponding seed oils. Lipids from roasted seeds of sesame, flax and soybean exhibited relatively higher viscosity and free fatty acids, than lipids from unroasted seeds. With an increase in roasting temperatures the colour of the oils were slightly darker even though the changes were not significant in most cases. The content of alpha- and gamma-tocopherols in oils (except soybean oil) gradually decreased as roasting temperature increased. beta-tocopherol was higher in the oils of roasted seeds, while the amount of delta-tocopherol showed different trends with roasting depending on the type of seeds. For sesame and poppy oils, after roasting at 210 degrees C, stearic and oleic acids showed higher percentages when compared to the levels in oils roasted at 90 and 150 degrees C.Öğe Characterisation of einkorn (Triticum monococcum L. subsp monococcum) wheat oil(Wageningen Academic Publishers, 2015) Demir, M. K.; Unver, A.; Arslan, D.; Ucok, G.; Terlemez, F.; Turker, S.Einkorn (Triticum monococcum L.) is one of the ancient wheat varieties which is rich in various functional components. The present research evaluated peroxide, refractive index, fatty acids composition, total carotenoids, chlorophyll content and colour values of einkorn grain and its oil. Total phenolic content and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity analyses were performed with whole wheat, defatted wheat and wheat oil. Whole wheat extract showed a higher total phenolic content and radical scavenging activity than defatted wheat and wheat oil extracts. The results showed that almost all of the phenolic compounds do not transfer during extraction from whole wheat to the wheat oil. Total oil yield of einkorn wheat was 1.58%. A major part of the composition of fatty acids in einkorn wheat oil was linoleic (49.43%), oleic (34.34%) and palmitic acid (10.27%). Total carotenoids in einkorn wheat oil was averaged as 12.33 mg/kg, total chlorophyll content was 0.73 mg/kg.Öğe Chemical characteristics and antioxidant activity of Olive oils from Turkish varieties grown in Hatay province(Elsevier Science Bv, 2012) Arslan, D.; Schreiner, M.Monovarietal virgin olive oil from five different Turkish varieties (Egriburun, Karamani, Halhali, Saurani and Hasebi) from Hatay province which were harvested on three different occasions have been analyzed to evaluate minor components (phenolic compounds, tocopherols and pigments), fatty acid profiles and antioxidant activity in order to determine the effects of both the nature of the variety and the time of harvest. The high total phenolics, secoiridoid aglycones, alpha-tocopherol and antioxidant activity of Saurani variety makes the oil of this variety superior to other varieties analyzed in this study. After evaluating the correlation matrix of the data set, the variables such as secoiridoids (3,4-DHPEA-EDA; 3,4-DHPEA-EA; p-HPEA-EDA and p-HPEA-EA), some of the phenolic compounds (hydroxytyrosol, vanillic acid and luteolin) and oxidation parameters (beta carotene bleaching activity, peroxide value and free fatty acids) were finally decided as the three factors which led to explore the underlying pattern of relationships by using principal component analysis. (C) 2012 Elsevier B.V. All rights reserved.Öğe Enzymatic pre-treatment in cold pressing: Influence on flaxseed, apricot kernel and grape seed oils(Consejo Superior Investigaciones Cientificas-Csic, 2021) Candan, A.; Arslan, D.A commercial enzyme preparation consisting of pectolytic, cellulotic and hemicellulotic enzymes was applied to the oil extraction by cold pressing from apricot kernel, flaxseed and grape seed. The e ffects o f e nzyme p re-treatment v aried d epending on the different oil seed used as raw material. Although the increase in free fatty acidity can be considered as a negative effect (from 0.37 to 0.52), the decrease in peroxide number and p-anisidine values, increase in oil yield (22.75%), higher levels of total carotenoids and tocopherols, as well as a remarkable increase in phenolic content (x1.68) and radical scavenging effect (including hydrophilic and lipophilic-induced and total antioxidant capacity) showed that the use of enzyme application in the cold pressing of apricot kernel oil would be beneficial. Many of these positive results could not be achieved in the pressing of flaxseed or grape seed oils under the same conditions. A high negative correlation (r=-92.2) was found between p-anisidine value and d-tocopherol for grapeseed oil. Hydrophilic and lipophilic antioxidant capacity, total phenolics, and total carotenoids negatively correlated well (r values above 80) with peroxide values for apricot seed oil. Correlation results showed that carotenoids play an important role in the oxidative stability of the oils, where it was much more evident for apricot seed oil (r=-97.5).Öğe INVESTIGATION OF COMBINED ULTRASOUND AND MICROWAVE PRETREATMENTS AND ENZYME ADDITION ON THE MAIN PHENOLICS AND SOME QUALITY PARAMETERS OF OLIVE OIL(Akademiai Kiado Zrt, 2018) Acar, A.; Arslan, D.Olive oil was obtained by applying laboratory scale microwave (MW) and ultrasound (US) technologies and enzymes (E) after olive crushing and malaxation. The effects of these technologies on some physical and chemical properties of olive oil have been examined with focus on phenolics in olive oil. The aim was to evaluate the combined effect of MW and US applications and E to olive paste by comparing with conventional production. The secoiridoids were present with lower values in US applied samples; as an example, the amount of 3-4-DHPEA-EDA in US treated sample was 59.36 mg kg(-1) oil, whereas its amount was 92.36 mg kg(-1) in the sample of conventional extraction. US resulted in the highest decrease (62%), and MW+US condition resulted in the lowest decrease (25.7%) in terms of total phenolics content. The US and MW pretreatments resulted in more advantageous properties in terms of free acidity, peroxides, and phenolics when applied together than their single applications.Öğe INVESTIGATION OF COMBINED ULTRASOUND AND MICROWAVE PRETREATMENTS AND ENZYME ADDITION ON THE MAIN PHENOLICS AND SOME QUALITY PARAMETERS OF OLIVE OIL(Akademiai Kiado Zrt, 2018) Acar, A.; Arslan, D.Olive oil was obtained by applying laboratory scale microwave (MW) and ultrasound (US) technologies and enzymes (E) after olive crushing and malaxation. The effects of these technologies on some physical and chemical properties of olive oil have been examined with focus on phenolics in olive oil. The aim was to evaluate the combined effect of MW and US applications and E to olive paste by comparing with conventional production. The secoiridoids were present with lower values in US applied samples; as an example, the amount of 3-4-DHPEA-EDA in US treated sample was 59.36 mg kg(-1) oil, whereas its amount was 92.36 mg kg(-1) in the sample of conventional extraction. US resulted in the highest decrease (62%), and MW+US condition resulted in the lowest decrease (25.7%) in terms of total phenolics content. The US and MW pretreatments resulted in more advantageous properties in terms of free acidity, peroxides, and phenolics when applied together than their single applications.
