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Öğe Application of multivariate chemometric techniques for simultaneous determination of five parameters of cottonseed oil by single bounce attenuated total reflectance Fourier transform infrared spectroscopy(ELSEVIER, 2014) Talpur, M. Younis; Kara, Huseyin; Sherazi, S. T. H.; Ayyildiz, H. Filiz; Topkafa, Mustafa; Arslan, Fatma Nur; Naz, SabaSingle bounce attenuated total reflectance (SB-ATR) Fourier transform infrared (FTIR) spectroscopy in conjunction with chemometrics was used for accurate determination of free fatty acid (FFA), peroxide value (PV), iodine value (IV), conjugated diene (CD) and conjugated triene (CT) of cottonseed oil (CSO) during potato chips frying. Partial least square (PLS), stepwise multiple linear regression (SMLR), principal component regression (PCR) and simple Beer's law (SBL) were applied to develop the calibrations for simultaneous evaluation of five stated parameters of cottonseed oil (CSO) during frying of French frozen potato chips at 170 degrees C. Good regression coefficients (R-2) were achieved for FFA, PV, IV, CD and CT with value of > 0.992 by PLS, SMLR, PCR, and SBL. Root mean square error of prediction (RMSEP) was found to be less than 1.95% for all determinations. Result of the study indicated that SB-ATR FTIR in combination with multivariate chemometrics could be used for accurate and simultaneous determination of different parameters during the frying process without using any toxic organic solvent. (C) 2014 Elsevier B.V. All rights reserved.Öğe Bitkisel yağ analizleri için geciktirmeli ve ön deriştirmeli SPE sistemlerinin FIA-HPLC sistemlerine entegrasyonu ve uygulamalarının geliştirilmesi(Selçuk Üniversitesi Fen Bilimleri Enstitüsü, 2015-09-30) Arslan, Fatma Nur; Kara, HüseyinBitkisel yağlar esas olarak trigliserit molekülleri ve farklı kimyasal yapılı bileşiklerin oluşturduğu kompleks bir karışım olan minör bileşenlerden oluşmaktadır. Trigliserit molekülleri yağ içerisinde yüksek miktarda bulunmaları (~95-98%) nedeniyle temel bileşenler; karakteristik özellikleri kazandıran minör bileşenler (~5-2%) ise ikincil bileşenler olarak adlandırılmaktadır. Yağların kalitesi, kaynağı, tağşişi ve diğer bazı özelliklerinin belirlenebilmesi için, yağlarda bulunan bir çok bileşenin çeşitli analitik yöntemler kullanılarak tayin edilmesi gerekmektedir. Bu tayinler genellikle standart metotlar olarak bilinen metotlar kullanılarak gerçekleştirilmektedir. Yağların özelliklerinin belirlenmesinde kullanılan standart metotların uygulamaları ve gerektirdiği ön işlemler; oldukça maliyetli, zaman alan, zahmetli ve çevre açısından tehlike oluşturan çözücülerin fazla miktarda kullanımını gerektirmektedir. Bu nedenle; uygulanmakta olan standart metotlara alternatif olabilecek, çevre dostu yeni yağ analiz metotlarının geliştirilmesi gerekmektedir. Sunulan çalışma ile; birçok yağ analizinin ön işlem basamağında yer alan SPE tekniğinin, FIA ve HPLC sistemlerine entegrasyonu ile, bitkisel yağlarda mevcut türlerin tek bir enjeksiyon ile 3 boyutlu kromatografik tayinleri için; numune ön işlemlerinin on-line gerçekleştirilebildiği ve analizci müdahalesinin en aza indirildiği "On-line SPE-FIA-HPLC yağ analiz sistemi" oluşturulmuş ve sistem üzerinde yeni yağ analiz metotlarının geliştirilip/ uygulanabilirliği gerçekleştirilmiştir. Dünyada ve Türkiye'de ilk kez geliştirilen bu yeni analiz sistemi; HPLC sistemine değişik özelliklerdeki kolon, dedektör, çok yollu valf sistemleri ve bağlantı elamanlarının adapte edilmesi ile oluşturulmuştur. Yağların özelliklerinin belirlenmesinde önem arz eden ve genellikle standart metotlar kullanılarak gerçekleştirilen trigliserit, sterol, tokol, digliserit, monogliserit, FFA ve fosfolipit tayinlerinin her birisi, oluşturulan bu yeni sistem üzerinde denenmiş ve önemli deneysel parametrelerin optimizasyon çalışmaları gerçekleştirilmiştir. Deneysel parametrelerin optimizasyonu için kemometrik yaklaşım izlenerek deneysel tasarım çalışmaları uygulanmıştır. Optimum parametreler kullanılarak yürütülen analizler için; lipit standartlarının yanında ayçiçek, mısır, pamuk, soya, kanola, palm, zeytinyağı gibi farklı özellikteki bitkisel yağ numuneleri de kullanılmıştır. Sonuç olarak; bitkisel yağların özelliklerini belirlemede önem arz eden tayinlerin tamamının, numune ön işlemlerinin on-line gerçekleştirildiği tek bir analiz sistemi üzerinde, tek bir enjeksiyon ile yapılabilirliği dünya literatüründe ilk kez önerilmiş ve kapsamlı bir şekilde incelenmiştir. Elde edilen veriler neticesinde; yağlarda mevcut lipit türlerinin tayini için daha kısa sürede, yüksek oranda iyileştirilmiş ayrımların elde edilebildiği analizler gerçekleştirilebilmiştir. Çalışmanın sanayi uygulaması ile; ülkemiz yağ sektörü açısından son derece önem arz eden analizlerin, otomatikleştirilmiş sistemlerde gerçekleştirilmesine imkan sağlanacaktır. Yağlarda mevcut farklı fiziksel ve kimyasal özelliklere sahip önemli türlerin tayini için; özel bir sistem dizaynı ve enstrümantasyonu ile tamamlanan bu yeni sistem uygulamasının, "modern birleştirilmiş analiz sistemlerinin geliştirilmesi ve uygulamaları" ile ilgilenen araştırmacılar için yeni ufuklar açacağı kanaatindeyiz.Öğe Central composite design and response surface methodology for the optimization of Ag+-HPLC/ELSD method for triglyceride profiling(SPRINGER, 2017) Arslan, Fatma Nur; Kara, HuseyinThe study presents the application of central composite design (CCD) and response surface methodology (RSM) for the optimization of silver-ion normal phase HPLC/ELSD (Ag+-HPLC/ELSD) method parameters to profile the isomers of triglycerides in vegetable oils. The significance of a second-order polynomial model for predicting the optimal values of Ag+-HPLC/ELSD method parameters was evaluated by the analysis of variance, ANOVA, and 3D response surface plots for the interactions between three variables were constructed. Three experimental parameters were chosen as independent variables which are the flow rate of mobile phase, temperature of column compartment and concentration of sample. A multivariate five-level CCD and RSM were used to confirm a quadratic model as a functional relationship between the response values (Rs, N, alpha and k') and variables. The optimum values of parameters were found to be a flow rate of 1.25 mL min(-1), temperature of column compartment of 20 A degrees C, and sample concentration of 5 x 10(-2) mg A mu L-1. Regression analysis with an R-2 values indicated as an adequate correlation between the experimental and predicted response values. ANOVA test results were also confirm that the models can be successfully used to predict the optimum parameters of Ag+-HPLC/ELSD method. Therefore, the proposed model provides an efficient, automated, and robust Ag+-HPLC/ELSD method for triglyceride profiling and is also suitable for a number of applications and analytical method developments for vegetable oils.Öğe A Chemometric Approach to Assess the Frying Stability of Cottonseed Oil Blends During Deep-Frying Process: Fatty Acid Composition and Tocopherol Analyses(TAYLOR & FRANCIS INC, 2015) Arslan, Fatma Nur; Kara, Huseyin; Talpur, M. Younis; Sherazi, Syed Tufail HussainThe aim of the present study was to determine impacts of different additives on fatty acid composition and total tocopherol content of cottonseed oil during deep-frying process using a chemometric approach. A quarter-fractional factorial design with two levels and five factors was used for preparing the frying cottonseed oil blends. In the experimental design, additives were such as ascorbic palmitate, mixed tocopherols, dimethylpolysiloxane, lecithin, and sesame oil were used as factors. The effect of additives on fatty acid composition and tocopherol content were evaluated with normal distribution (ND) graphs during ten hours frying at 170 +/- 5 degrees C. The data were statistically assessed by one-way analysis of variance at a significance level of p < 0.05. The analysis of variance test results were in good agreement with ND graphs and data indicated that the interaction between ascorbic palmitate and dimethylpolysiloxane (A x C factor) showed a significant and protective effect on fatty acids. Meanwhile, the sesame oil (E factor) and A x C factor were showed a significant effect on level of tocopherols. The results of study indicated that present approach could be used to assess and improve the frying stability of any oil with respect to fatty acid composition and tocopherols.Öğe A Chemometric Approach to Assess the Frying Stability of Cottonseed Oil Blends During Deep-Frying Process: I. Polar and Polymeric Compound Analyses(WILEY, 2013) Arslan, Fatma Nur; Kara, Huseyin; Ayyildiz, Hamide Filiz; Topkafa, Mustafa; Tarhan, Ismail; Kenar, AdnanThe main goal of the present study was (i) to determine the formation of degradation products in cottonseed oil (CSO) blends during deep frying process by adsorption and high performance size exclusion chromatography techniques and (ii) to evaluate the impacts of food additives on total polar (TPC) and polymeric compound (PTAG) formation using a chemometric approach. In order to prepare the frying CSO blends; ascorbic palmitate, mixed tocopherols, dimethylpolysiloxane, lecithin and sesame oils were used as additives. To determine the real impacts of additives, a quarter-fraction factorial experimental design with two levels and five factors was used. The changes in TPC and PTAG data were carefully evaluated during 10 h of frying at 170 +/- A 5 A degrees C with normal distribution (ND) graphs and analyzed using a one-way analysis of variance (ANOVA), followed by Tukey's Post-hoc test (alpha = 0.05). The results indicated that the increasing values for TPC and PTAG during the frying processes for all blends, TPC and PTAG contents reached maximum levels of 16.37 and 6.01 % respectively, which are below the limit values stated by official authorities for the quality assessment of frying oils. The ANOVA test results were in good agreement with ND graphs and data indicated that the impact of mixed tocopherols was significant for TPC formation, meanwhile the impact of lecithin and ascorbic palmitate x dimethylpolysiloxane were significant for PTAG formation. Thus, the present study should be considered to be a very useful guide for developing new frying oil formulations based on CSO by using food additives.Öğe Fully Automated Three-Dimensional Column-Switching SPE-FIA-HPLC System for the Characterization of Lipids by a Single Injection: Part I. Instrumental Design and Chemometric Approach to Assess the Effect of Experimental Settings on the Response of ELSD(SPRINGER, 2016) Arslan, Fatma Nur; Kara, HuseyinThis article presents the first application of fully automated three-dimensional (3D) column-switching SPE-FIA-HPLC system for the characterization of lipids by a single injection. The whole system was designed and set up by modifying Agilent 1200 Series HPLC system in our laboratory. By using this system, a complete separation profile of the oil samples was achieved in a very short time period by using single injections. This approach was applied on vegetable oils which contains a large number of relatively high-class lipid components, such as TG, FFA, sterols, tocopherols, DG, ester and MG. In this part of the study, we focused on the optimization of evaporative light scattering detector (ELSD) by using an experimental design and RSM. Three experimental parameters were chosen as an independent variables which are the flow rate of mobile phase, nebulization temperature and evaporation temperature. A multivariate five level experimental design was used to establish a quadratic model as a functional relationship between the response values and independent variables. The optimal values of parameters were found to be a flow rate of 1.25 mL min(-1), nebulization temperature of 80 degrees C, and evaporation temperature of 40 degrees C. Regression analysis with an R-2 values indicated as a satisfactory correlation between the experimental and predicted values. ANOVA test results were also illustrate that the models can be successfully used to predict the optimum parameters of ELSD. Thus, the proposed system is suitable for a large number of applications including research and development of new quality control and characterization methods for vegetable oils.Öğe Role of Different Bleaching Earths for Sunflower Oil in a Pilot Plant Bleaching System(DE GRUYTER OPEN LTD, 2013) Topkafa, Mustafa; Ayyildiz, H. Filiz; Arslan, Fatma Nur; Kucukkolbasi, Semahat; Durmaz, Fatih; Sen, Seyit; Kara, HuseyinThe purpose of present study is to investigate the efficiency of different kinds of Turkish commercial bleaching earth materials for changes in different colour pigment concentrations in neutralized sunflower oils. The bleaching experiments were performed in a pilot system under at stable vacuum (50 mmHg) and temperature (100 degrees C) for 30 min. By examining the changes in chlorophyll, beta-carotene and red colour, bleaching process parameters such as type and dosage of the bleaching material were optimised. The sorption characteristics of colour pigments were evaluated using common adsorption isotherms and Scatchard plot analysis. Ads-3 acid-activated earth material at 1% (w/w) per samples was found to be the most appropriate sorbent and the amount of sorbed pigments was calculated as 1.01x10(-4)mmol/g ads. for chlorophyll, 1.15x10(-3)mmol/g ads. for carotene and 1.70 red on Lovibond colour scale. The procedure indicated that this system can be easily adapted to the actual oil refining systems.Öğe A study on monitoring of frying performance and oxidative stability of cottonseed and palm oil blends in comparison with original oils(TAYLOR & FRANCIS INC, 2017) Arslan, Fatma Nur; Sapci, Ayca Nesibe; Duru, Fatma; Kara, HuseyinBlending polyunsaturated oils with highly saturated or monounsaturated oils has been studied extensively; however, in literature there is negligible information available on the blending of refined cottonseed oil with palm olein oil. Blending could enhance the stability and quality of cottonseed oil during the frying process. In the present study, the effects of frying conditions on physicochemical properties of the palm olein-cottonseed oil blends (1:0, 3:2, 1:1, 2:3, and 0:1, w/w) were determined and compared to the pure oils. The frying process of frozen French fries was performed in duplicate at 170 +/- 5 degrees C for 10 h without interruption. The oil degradations were characterized during deep-frying applications; peroxide, free fatty acid, and iodine value by standardized methods, fatty acid profile by using a gas chromatography-flame ionization detector, polar and polymeric compounds by using the high-performance size exclusion chromatography/evaporative light scattering detector technique. The present study clearly indicated that the oxidative and frying performances of pure palm olein oil and cottonseed oil significantly improved by blending application. Results clearly indicated that the frying performance of cottonseed oil significantly improved by the blending with palm olein oil. Except that free fatty acid content, all the physicochemical variables were significantly influenced by type of pure and blend oils. By increasing the proportion of palm olein oil in cottonseed oil, the levels of polyunsaturated fatty acids decreased, while saturated fatty acid content increased. The progression of oxidation was basically followed by detecting polar and polymeric compounds. The fastest increments for polar and polymeric compounds were found as 6.30% level in pure cottonseed oil and as 7.07% level in 40% cottonseed oil:60% palm olein oil blend. The least increments were detected as 5.40% level in 40% cottonseed oil:60% palm olein oil blend and 2.27% level in 50% cottonseed oil:50% palm olein oil blend. These levels were considerably below the acceptable levels recommended by the official codex. Therefore, the present study suggested that blending of cottonseed oil with palm olein oil provided the oil blends (50% cottonseed oil:50% palm olein oil and 40% cottonseed oil:60% palm olein oil, w/w) with more desirable properties for human nutrition.Öğe Ülkemizde üretilen pamuk yağlarının rafinasyonunun iyileştirilmesiyle kullanım verimliliklerinin artırılması(Selçuk Üniversitesi Fen Bilimleri Enstitüsü, 2009) Arslan, Fatma Nur; Kara, HüseyinBitkisel yağ sektöründe önemli pay sahibi olan ve üretimi ilk sıralarda yer alan pamuk yağının rafinasyonu ülkemizde istenilen ölçüde gerçekleştirilemediği için, pamuk yağı kullanılarak elde edilen gıda ürünlerinin raf ömürleri kısalmakta ve ürün kalitesi düşmektedir. Pamuk yağı kalitesinin ve kullanım verimliliğinin artırılması ve pamuk yağından elde edilecek gıda ürünlerinin besin kalitelerinin yükseltilmesi amacıyla gerçekleştirilen bu çalışma; pamuk yağı rafinasyon şartlarının iyileştirilmesi ve rafinasyonu iyileştirilen pamuk yağının kızartmalık yağ olarak kullanım verimliliğinin incelenmesi olmak üzere iki aşamada gerçekleştirilmiştir. Pamuk yağı rafinasyon şartlarının düzeltilmesi için gerçekleştirilen çalışmalar; yüksek kalitede pamuk yağı üretimi için en önemli rafinasyon basamağı olduğu düşünülen ağartma basamağı üzerinde yoğunlaşılarak gerçekleştirilmiş ve ağartma kademesinde kullanılan parametreler optimize edilmiştir. Yüksek kalitede rafine edilen pamuk yağının, kızartmalık yağ olarak kullanım verimliliğinin incelenmesi amacıyla gerçekleştirilen denemeler için; pamuk yağına çeşitli gıda katkı maddeleri (anti-oksidant, köpük ve sıçrama kesici, kıvam artırıcı vb.) ilave edilerek kızartmalık yağ karışımları hazırlanmıştır. Kızartmalık yağa göre her yarım saatte %8 oranında patates dilimlerinin kullanılarak 170±5 ºC'de, 10 saat süreyle 20 kez kesintisiz şekilde kızartma işlemleri gerçekleştirilmiştir. Kızartma işlemleri sonucunda; kızartmalık yağların kalitesini belirlemede önemli bir parametre olan polar madde miktarı en fazla %17'ye ulaşmış olup, bu değer Avrupa Birliği Mevzuatı ve Türk Gıda Kodeksi tarafından öngörülen maksimum %25 olan limit değerin altında yer almaktadır. Seçkin tat ve kararlılığına, uygun oranda yağ asit kompozisyonuna, yüksek dumanlama noktasına sahip olan ve diğer bitkisel yağlardan kolaylıkla ayırt edilebilen özellikle de kızartmalar için ideal olan pamuk yağının yüksek kalitede rafinasyonu ile; ülkemizde üretilen pamuk yağlarının yerli ve yabancı pazar paylarının arttırılması, pamuk yağı kullanılarak elde edilecek olan gıda ürünlerin beslenme kalitesinin yükseltilmesi ve ithal olarak ülkemize giren ticari kızartmalık yağlar ile rekabet edilerek ülke ekonomisine katkıda bulunulması umut edilmektedir.
