Food Engineering / Gıda Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/12
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Review Citation - WoS: 10Citation - Scopus: 10Authentication of Vinegars With Targeted and Non-Targeted Methods(Taylor & Francis, 2023) Çavdaroğlu, Çağrı; Çavdaroğlu, Çağrı; Özen, Banu; Özen, Fatma BanuThere has been a growing interest in vinegar, especially after the increasing reports about its beneficial health effects. Bioactive compounds of vinegar are associated with its antimicrobial, antioxidant, antidiabetic, antitumor, and anti-obesity types of activities. Quality of vinegar is related with the authenticity of the product besides the amounts of bioactive compounds in its composition. Addition of cheaper substitutes to higher quality vinegars and false labeling are some common authentication problems for this product. There are various examples of the use of targeted and untargeted methods in authentication studies for vinegars. Specific constituents and properties of vinegars such as molecular isotope ratios and individual volatile compounds were used to detect adulteration with targeted methods. On the other hand, untargeted methods, mostly in the form of the application of spectroscopic techniques, such as infrared and fluorescence spectroscopy in combination with chemometrics, provide an overall measurement. This review mainly focuses on adulteration types and elaborates on different targeted and non-targeted methods used to authenticate vinegars.Article Citation - WoS: 35Citation - Scopus: 43Potential of Fourier-Transform Infrared Spectroscopy in Adulteration Detection and Quality Assessment in Buffalo and Goat Milks(Elsevier, 2021) Şen, Sevval; Dündar, Zahide; Uncu, Oğuz; Özen, BanuAdulteration of higher priced milks with cheaper ones to obtain extra profit can be the cause of adverse health effects as well as economic loss. In this study, it was aimed to differentiate goat-cow and buffalo-cow milk mixtures and also to estimate the critical quality parameters of these milks by the evaluation of Fourier-transform infrared (FTIR) spectroscopic data with chemometric methods. Raw goat and buffalo milks were mixed with cow milk at 1-50% (v/v) concentrations and FTIR spectra of the pure and mixed samples were obtained at 4000-650 cm-1. Orthogonal partial least square discriminant analysis (OPLS-DA) resulted in differentiation of goat-cow and buffalo-cow milk mixtures with 93% and 91% correct classification rates, respectively. Detection level for mixing is determined as higher than 5% for both milks. Total fat, protein, lactose and non-fat solid contents were predicted from FTIR spectral data of the combination of three types of milks by partial least square models with R2 values of 0.99. As a result, FTIR spectroscopy provides rapid and simultaneous detection of adulteration and prediction of quality parameters regardless of the milk type.Article Citation - WoS: 13Citation - Scopus: 14Uv-Vis Spectroscopy for the Estimation of Variety and Chemical Parameters of Olive Oils(Springer, 2021) Jolayemi, Olusola Samuel; Tokatlı, Figen; Özen, BanuOlive oils produced in different years from different varieties were studied with UV-Vis spectroscopy for classification and prediction. Multivariate models were created with second derivative spectral data, and tested with external validation sets. For varietal classification, orthogonal partial least square discriminant analysis resolved oil samples into various classes with correct classification rate more than 89% for validation set (n = 20). A sample of fresh and stored oils were also classified with a correct classification rate more than 90% for validation set (n = 20). In the predictions of chemical parameters (70 for calibration, 30 for validation), the combination of UV-Vis spectroscopy with orthogonal partial least square regression models showed potential for simultaneous quantification of chlorophylls (0.6-5.6 mg/kg; R-val(2) , 0.79; RPD, 1.97); carotenoids (0.6-3.3 mg/kg; R-val(2), 0.80; RPD, 2.38); ratio of mono to polyunsaturated fatty acids (3.6-8.8; R-val(2) , 0.77; RPD, 1.90), oleuropein derivatives (1.2-62.3 mg/kg; R-val(2) , 0.66; RPD, 1.77), and total phenol content (62.2-505 mg/kg; R-val(2) , 0.67; RPD, 1.74), although showed poor to moderate results for the quantification of free fatty acid (0.3-5.4%; R-val(2), 0.67; RPD, 1.64); monounsaturated fatty acids (66-76.5%; R-val(2) , 0.71; RPD, 1.67); polyunsaturated fatty acids (8.6-18.2%; R-val(2) , 0.73; RPD, 1.65). The models were unable to estimate oxidative stability, saturated fatty acids, and individual phenolics such as hydroxytyrosol, pinoresinol, luteolin, total phenolic acids (R-val(2) , 0.26-0.64; RPD, 0.60-1.52). Results showed the capacities of UV-Vis spectroscopy for classification of olive oils, and prediction of total pigments and phenol content and ratio of mono to polyunsaturated fatty acids.Article Citation - WoS: 9Citation - Scopus: 11Prediction of Vinegar Processing Parameters With Chemometric Modelling of Spectroscopic Data(Elsevier, 2021) Çavdaroğlu, Çağrı; Çavdaroğlu, Çağrı; Özen, Banu; Özen, Fatma BanuSpectroscopic methods have the advantages of being rapid and environmentally friendly and can be used in measurement and control of processing parameters during food production. It was aimed to predict several quality and chemical parameters of vinegar processing from UV-visible and mid-infrared spectroscopic profiles. Two processing lines of both traditional and submerged vinegar production from 2 separate grape varieties (green and red grapes) were monitored. Some of the important markers of the fermentation processes; pH, brix, total acidity, total flavonoid content, total and individual phenolic contents, organic acid, sugar, ethanol concentrations as well as UV-visible and mid-infrared spectra were obtained during both types of vinegar processing and quality and chemical parameters were predicted from spectroscopic data using chemometric methods. Individual UV-visible and mid-infrared spectral profiles along with low level of data fusion were used in building of chemometric prediction models. Accurate, reliable and robust prediction models (R(2)cal and R(2)val >0.9) were obtained for quality parameters mostly with combination of two spectroscopic datasets. Predictive models used for phenolic components were below average except for p-coumaric and syringic acids. Citric and acetic acids were the most accurately estimated ones among organic acids along with ethanol. Close agreements between reference and predicted values were obtained during the monitoring of changes of some quality parameters for vinegar fermentation process through rapid and simultaneous spectroscopic measurements.Article Citation - WoS: 25Citation - Scopus: 30Prediction of Chemical Parameters and Authentication of Various Cold Pressed Oils With Fluorescence and Mid-Infrared Spectroscopic Methods(Elsevier Ltd., 2021) Doğruer, Ilgın; Uyar, H. Hilal; Uncu, Oğuz; Özen, BanuIt was aimed to compare the performances of two spectroscopic methods, fluorescence and mid-infrared spectroscopy, in terms of their adulteration detection and estimation of several chemical properties for various cold pressed seed oils. Spectroscopic profiles, fatty acid, free fatty acid and total phenol contents of pumpkin seed, grape seed, black cumin oil, and sesame seed oils were determined and these oils were mixed with sunflower oil at 1–50% (v/v). Both spectroscopic techniques provided comparable results for determination of adulteration of each oil type and the most successful prediction was obtained for pumpkin seed oil at levels >%1. Combined data set of oils resulted in successful quantification of their free fatty acid value, total phenol and major fatty acids contents with both spectroscopic methods regardless of oil type. Both techniques could be used as reliable, fast and environmentally friendly alternatives in the analyses of different types of seed oils. © 2020 Elsevier LtdArticle Citation - WoS: 82Citation - Scopus: 103A Comparative Study of Mid-Infrared, Uv-Visible and Fluorescence Spectroscopy in Combination With Chemometrics for the Detection of Adulteration of Fresh Olive Oils With Old Olive Oils(Elsevier Ltd., 2019) Uncu, Oğuz; Uncu, Oğuz; Özen, Banu; Özen, Fatma BanuThe work aimed to detect and quantify adulteration of fresh olive oils with old olive oils from the previous harvest year by using different spectroscopic approaches in combination with chemometrics. Adulterated samples prepared in varying concentrations (10.50%(v/v)) were analyzed with fluorescence, Fourier transform-infrared (FT-IR), and ultraviolet-visible (UV-vis) spectroscopic methods. Orthogonal partial least square-discriminant analysis (OPLS-DA) and partial least squares (PLS) regression techniques were used for the differentiation of adulterated oils from the pure oils and prediction of adulteration levels, respectively. After the application of various pre-treatment methods, all of the OPLS-DA classification models generated for every spectroscopic technique successfully differentiated adulterated and non-adulterated oils with over 90% correct classification rate. FT-IR + UV-vis and fluorescence spectral data were also successfully used to predict adulteration levels with high coefficient of determinations for both calibration (0.94 and 0.98) and prediction (0.91 and 0.97) models and low error values for calibration (4.22% and 2.68%), and prediction (5.20% and 2.82%), compared to individual FT-IR and UV-vis spectroscopy were obtained. Therefore, FT-IR + UV-vis and fluorescence spectroscopy as being fast and environmentally friendly tools have great potential for both classification and quantification of adulteration practices involving old olive oil.Article Citation - WoS: 12Citation - Scopus: 15Effects of Processing Parameters on Chemical and Physical Properties of Enzymatically Interesterified Beef Tallow-Corn Oil Blends(John Wiley and Sons Inc., 2020) Aktaş, Ayşe Burcu; Özen, Banu; Alamprese, Cristina A.The purpose of this study was to improve some physical and chemical characteristics of tallow through enzymatic interesterification process with corn oil and to investigate effects of process parameters on chemical and physical properties of obtained products. Full factorial design was constructed using blend ratio and reaction time as process parameters. Enzymatic interesterification was catalyzed with sn-1,3-specific lipase. Interesterified lipids have higher free fatty acid content and lower oxidative stability compared to initial blends. Interesterification did not cause trans-fatty acid formation and products mostly contained beta crystals. Solid fat content and slip melting point decreased up to 6 hr of interesterification; however, longer reaction times have negative effects on these parameters. Statistical analyses' results confirmed that reaction time is highly important for enzymatic interesterification. Practical applications Some of interesterified lipids can be utilized as alternatives to margarines or butterfat due to their lower trans-fatty acid content and crystal morphology.Article Citation - WoS: 14Citation - Scopus: 18Evaluation of Three Spectroscopic Techniques in Determination of Adulteration of Cold Pressed Pomegranate Seed Oils(Elsevier Ltd., 2020) Uncu, Oğuz; Napiórkowska, Alicja; Szajna, Tomasz K.; Özen, BanuIt was aimed to compare three spectroscopic methods in determination of adulteration of cold pressed pomegranate seed oils (PSOs) with sunflower oil in this research. UV–visible, mid-infrared and fluorescence spectra of pure and adulterated pomegranate oils (1–50%, v/v) were collected and data were analyzed with multivariate statistical analysis techniques. According to orthogonal partial least square discriminant analysis, best differentiation between pure and mixed samples was obtained with mid-infrared spectroscopy having 100% success rate. Fluorescence and UV–visible spectroscopy also provided good discrimination between samples with 96 and 88% successful classification rates, respectively. As a result of partial least square regression analysis, detection limits for mid-infrared, UV–visible and fluorescence spectroscopies are determined as >1, 5 and 10% in order. Since all spectroscopic methods provided detection of mixtures of cold pressed PSOs with sunflower oil at low concentrations they could serve as easy to use and rapid techniques in control laboratories. © 2020 Elsevier B.V.