Yazar "Talpur, M. Younis" seçeneğine göre listele

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    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, Saba
    Single 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.
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    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 Hussain
    The 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.
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    Determination of Unsaponifiable Constituents of Deodorizer Distillates by GC-MS
    (SPRINGER, 2012) Naz, Saba; Sherazi, S. T. H.; Talpur, Farah N.; Talpur, M. Younis; Kara, Huseyin
    Deodorizer distillate is an important by-product obtained during deodorization in the edible oil industries. It is a complex mixture of many health beneficial constituents like phytosterols, tocopherols and squalene. In the present study a simple gas chromatographic method with mass spectrometry was used for the separation, detection and quantification of different components present in the deodorizer distillate in a very short analysis time of 18 min. A simple saponification procedure without derivatization was used for their analysis followed by GC-MS analysis. Phytosterols concentration (21.27-25.53%) was the most abundant in canola and palm distillate samples whereas, squalene and tocopherol were present in concentration ranges of 2.89-13.21% and 1.29-5.81%, respectively. The present study revealed that the unsaponifiable fraction of deodorizer distillate could be used in cosmetic preparations due to its appreciable amount of bioactive constituents.
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    Oxidation on the Stability of Canola Oil Blended with Stinging Nettle Oil at Frying Temperature
    (TAYLOR & FRANCIS INC, 2015) Durmaz, Fatih; Talpur, M. Younis
    The present study was carried out to investigate changes in fatty acids composition and their ratio by mixing of canola oil (CLO) with cold pressed stinging nettle oil (SNO) during heating at 180 degrees C for 10 h, and analyzed by gas chromatography-mass spectrometry. The blended oils were prepared by gravimetrically mixing of CLO and SNO at various ratios of 60:40 and 40:60 w/w, respectively. Trans fatty acid in fresh CLO and SNO of 1.1 and 0.05%, whereas fresh blended oils of CLO:SNO (40:60, 60:40 w/w) contained 0.44, 0.91% and heated oils of CLO, SNO and CLO: SNO (40:60, 60:40 w/w) were found from 1.35 -2.49, 0.06 -0.09, and 0.46 -0.51, 1.02 -1.27%, correspondingly. The linolenic fatty acid is more prone to oxidation in heated oils and their percentage in fresh CLO, SNO and blended (40:60, 60:40) CLO:SNO samples of 10.58, 0.00, and 3.94, 6.64%, respectively. The linolenic acid was decreased from 10.27 -6.54, 0.00, and 3.93 -3.79%, 6.47 -5.68% in heated CLO, SNO and CLO:SNO (40:60, 60:40 w/w) oils, respectively. The oxidation parameters were also analyzed such as free fatty acids, peroxide value, iodine value, conjugated diene and triene using standard methods. The best results of free fatty acids, peroxide value, iodine value, conjugated diene and triene were obtained in blended CLO:SNO (40:60 w/w) oil at 0.31%, 0.63 meqO(2)/Kg, 0.79 g/100 g, 60 and 31.36% during 10 h. The obtained results show that mixing of CLO with SNO increased the stability against oxidation and consequently enhanced the worth of CLO during heating/frying route.
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    A simplified FIR chemometric method for simultaneous determination of four oxidation parameters of frying canola oil
    (PERGAMON-ELSEVIER SCIENCE LTD, 2015) Talpur, M. Younis; Hassan, S. Sara; Sherazi, S. T. H.; Mahesar, S. A.; Kara, Huseyin; Kandhro, Aftab A.; Sirajuddin
    Transmission Fourier transform infrared (FTIR) spectroscopic method using 100 mu m KCl cell was applied for the determination of total polar compounds (TPC), carbonyl value (CV), conjugated diene (CD) and conjugated triene (CT) in canola oil (CLO) during potato chips frying at 180 degrees C. The calibration models were developed for TPC, CV, CD and CT using partial least square (PLS) chemometric technique. Excellent regression coefficients (R-2) and root mean square error of prediction values for TPC, CV, CD and CT were found to be 0.999, 0.992, 0.998 and 0.999 and 0.809, 0.690, 1.26 and 0.735, respectively. The developed calibration models were applied on samples of canola oil drawn during potato chips frying process. A linear relationship was obtained between CD and TPC with a good correlation of coefficient (R-2 = 0.9816). Results of the study clearly indicated that transmission FTIR-PLS method could be used for quick and precise evaluation of oxidative changes during the frying process without using any organic solvent. (C) 2015 Elsevier B.V. All rights reserved.