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  • Öğe
    Zeytinyağı Aroma Kimyası ve Duyusal Değerlendirilmesi
    (Sidas Medya A.Ş., 2004) Yılmaz, Emin; Öğütçü, Mustafa
    Flavor and aroma are essential quality factors for the food materials. Over 100 volatiles have been determined in olive oils, and of them 30 has found to contribute the perceived aroma of the oil. Determination of the sensorials terms of the measured volatiles, comparison of the samples, conversion of the consumer preference language to understantable chemical terms are also imperative.
  • Öğe
    The effect of different pre-treatments on sensory characteristics of unformulated pulse-based beverages
    (Springer India, 2025) Yılmaz Tuncel, Neşe; Polat Kaya, Havva; Andaç, Ali Emre; Karagül Yüceer, Yonca; Tuncel, Necati Barış
    The objectives of this study were to evaluate the effects of specific pre-treatments-including dry milling (control), soaking-wet milling, blanching, blanching-alkaline soaking-dehulling, vacuum treatment, and germination-on the sensory and aroma characteristics of beverages (termed as milk analogues or milk substitutes) derived from chickpea, faba bean, and cowpea as primary ingredients. In line with these objectives, solid phase micro extraction-gas chromatography-mass spectrometry (SPME-GC-MS), gas chromatography-olfactometry (GCO), and descriptive sensory evaluation were conducted, coupled with principal component analysis. Hexanal, 2-pentylfuran, 1-hexanol, and 2-heptanone were the most abundant volatiles in pulse-based milk analogues regardless of the pulse type. Among them, hexanal was found in the highest amount in all types of milk analogues. Most of the pre-treatments, including blanching, which was applied to inactivate the lipoxygenase enzymes, resulted in a significant increase in hexanal content (p < 0.05). However, blanching-alkaline soaking-dehulling was the most effective treatment in reducing the off-notes. Germination of 48 h or longer contributed to the development of formation of undesirable flavours.
  • Öğe
    Physicochemical and functional properties of safflower protein isolate: Effect of drying methods and spray drying temperatures
    (Springer Heidelberg, 2025) Korkmaz, Fatma; Tuncel, Necati Barış
    In this study, the effects of the drying method and spray drying inlet air temperature on the color, surface morphology, hydrophobicity, powder and functional properties of safflower protein isolate were investigated. Safflower protein was extracted using the alkaline extraction and isoelectric precipitation method and then dried using freeze-drying and spray-drying at 140, 150, 160, 170, and 180 degrees C inlet air temperatures. When compared to the spray-dried samples, freeze-dried safflower protein isolate had lower cohesiveness (1.18) and better flowability (15.12%) with higher bulk density (0.31 g/cm3) and lower tapped bulk density (0.37 g/cm3). Additionally, its wetting time (9.00 s) was also found to be lower. On the other hand, spray-dried samples exhibited lighter color, higher foaming capacity (30.00-38.75%) and stability (87.50-89.17%), and emulsion activity (51.25-54.50%) and stability (85.76-87.51%) than the freeze-dried sample. Moreover, it was found that the foaming capacity and emulsion activity of safflower protein spray-dried at 140 degrees C were higher than those of other spray-dried samples. Overall, freeze-dried safflower protein showed better powder properties, while spray-dried samples had better functional properties. Consequently, it was shown that the choice of drying method and spray drying inlet air temperature were critical for the powder and functional properties of safflower protein.
  • Öğe
    Detecting carob powder adulteration in cocoa using near and mid-infrared spectroscopy: A comprehensive classification and regression analysis
    (Elsevier, 2025) Turgut, Sebahattin Serhat; Ayvaz, Hüseyin; Doğan, Muhammed Ali; Marin, Dolores Perez; Menevşeoğlu, Ahmed
    Cocoa powder is a globally traded food product, primarily produced in developing nations, with substantial economic importance. However, it is susceptible to adulteration with inexpensive materials such as carob flour, particularly in low concentrations too low to be detected by sensory methods. To address this issue, rapid analytical techniques such as vibrational spectroscopy combined with multivariate analysis could be beneficial for rapid and reliable detection of adulteration. In this study, spectral data were collected using four different infrared spectrometers: a benchtop FT-NIR system, two portable NIR instruments, and a benchtop FT-MIR-ATR. Samples included pure cocoa, pure carob, and their mixtures with carob concentrations ranging from 0 % to 60 %. Both classification and regression models were developed to detect and quantify the presence of carobs in cocoa powder. Classification models, including Random Forest (RF), Support Vector Machine (SVM), Multi-Layer Perceptron (MLP), k-Nearest Neighbors (kNN), Linear Discriminant Analysis (LDA), and Soft Voting Classifiers, demonstrated superior performance for discriminating between cocoa powder, carob powder, and cocoa-carob mixtures with the area under the receiver operating characteristic curve (AUC) scores achieving the level of higher than 0.99, particularly using the benchtop FT-NIR, one of the cost-effective portable NIR and FT-MIR-ATR devices. Similarly, regression models - RF, SVM, MLP, kNN, Partial Least Squares Regression, and Voting Regressor- exhibited robust predictive capabilities. Particularly, FT-MIR and portable NIR based models showed exceptional accuracy with RPD values exceeding 16 and 13, respectively, signifying their applicability in quality and process control. Key wavelength driving model predictions were identified using permutation feature importance for both regressors and classifiers. Overall, these findings highlight and prove the potential of NIR and MIR spectroscopy as rapid, robust, and non-destructive tools for screening and quality control in food authentication.
  • Öğe
    The efficiency of Thermosonication, Ultrasonication and pasteurization on the storage stability of fresh eggs
    (Elsevier Sci Ltd, 2025) Caner, Cengiz; Gedikoğlu Arslan, Pınar; Yüceer, Muhammed
    The effectiveness of ultrasonication (90 W 3.5 min.), thermosonication (52 degrees C, 90 W 3.5 min.), and pasteurization (57.5 degrees C, 25 min.) processes on the quality attributes (HU as Haugh unit, YI as yolk index, dry matter, pH, foam stability and relative foam capacity) and shell strength of fresh eggs were evaluated during storage period. The significant differences in HU values between the untreated group and the treated eggs began to be observed from the day-10. The significant differences were found in the HU both in the untreated group (47.95) and in the eggs treated with ultrasonication (55.56), thermosonication (63.64), and pasteurization (73.28), with the highest HU value found in the pasteurized eggs at day-30. It was observed that thermosonication treatments maintained higher YI values compared to the untreated group, with significant differences between the values. The pH of the albumen and yolk at all groups increased in the highest value with control (albumen 9.44 - yolk 6.44), ultrasonication (albumen 9.35 - yolk 6.34), thermosonication (albumen 9.37 - yolk 6.41), and pasteurization (albumen 9,40 - yolk 6.35). The albumen dry matter values tended to increase in all groups during the storage, with the lowest dry matter results observed in the ultrasonicated samples. The relative foam capacity (RWC) value of the eggs treated with ultrasonication (796) was higher than those of the control (626), thermosonication (735), and pasteurization (680) groups. It was highlighted that thermal treatment led to a decrease in the RWC values at day-30. The lowest shell strength values were observed in the thermosonication samples due to both the cavitation mechanism and heat. This study demonstrated that thermosonication process is efficacious in maintaining the quality attributes of the fresh shell eggs. It was found that the combination of ultrasound with heat particularly improved quality characteristics such as HU and YI. Thermosonication applications could be an important and effective alternative for enhancing the internal-quality attributes and increasing the storage stability of eggs.
  • Öğe
    Soil-driven terroir: Impacts on Vitis vinifera L. 'Karasakiz' wine quality and phenolic composition
    (Academic Press Inc Elsevier Science, 2025) Çelebi Uzkuç, Nesrin Merve; Uzkuç, Hasan; Kavdır, Yasemin; Hamzaoğlu, Fatmagül; Kırca Toklucu, Ayşegül
    'Karasakiz' (Vitis vinifera L.), is a local red grape variety native to Çanakkale, a province of Türkiye. This work aimed to characterize the phenolic profile of Karasakiz red wines and mainly investigate the effects of soil characteristics on the phenolic composition, antioxidant capacity, and color properties of the red wines produced. The study was conducted on three vineyards located in three different regions of Çanakkale, each with distinct chemical properties and textural characteristics, over two consecutive vintages (2019 and 2020). The phenolic profiles and color properties of red wines varied depending on the year and region, and were strongly influenced by soil texture. A strong correlation (r = 0.897 and P < 0.0001) was found between the percentage of sand in the soil and the total monomeric anthocyanin content of the wines. Total monomeric anthocyanin contents of Karasakiz wines ranged from 15.76 mg/L to 68.87 mg/L, while total phenolics ranged from 1238 mg/L to 1950 mg/L, with variations observed depending on the region and year. Additionally, a high positive correlation was observed between potassium concentration and the concentrations of ferulic acid and catechin in the wines. This study reveals the characteristic properties and phenolic composition of Karasakiz wines from different sub-regions, highlighting significant correlations in terms of the soil-wine relationship.
  • Öğe
    Trends in Sustainability and Innovative Food Packaging Materials: An Overview
    (Sidas Medya A.S., 2024) Caner, Cengiz; Yüceer, Muhammed; Harte, Bruce
    Globally, 1.3 billion tons of food are wasted or lost every year. This loss is valued at US $2.6 trillion and accounts for 8-10% of greenhouse gas emissions (GHG). Food waste is a significant source of greenhouse gas emissions and results in a waste of natural resources. Therefore, reducing food waste can help diminish GHG emissions, improve food security, and promote healthy food systems. Packaging plays an important role in protecting food, enhancing quality and safety, and reducing food losses. Innovative and sustainable packaging strategies are necessary to decrease waste accumulation, particularly of plastics, safeguard food quality and safety, and reduce food losses and waste. Sustainable packaging aims to enhance the effectiveness of design and the use of environmentally friendly materials. This review provides an overview of the sustainable status of common packaging materials such as plastic, glass, metal, and paper/cardboard based on the circular economy, which includes recycling, reuse, composting, and bio-based packaging. The study examines new developments in food packaging materials in response to the growing demand for environmentally sustainable alternatives. Several applications from food companies and sustainable studies are discussed regarding continuous availability without impacting the environment. Ongoing research and technological advancements, such as material reduction, the development of innovative new materials like bioplastics, and improvements in recycling, will contribute to increasing the acceptance of sustainable packaging. Definitions, requirements, limitations, legislation, and applications of sustainable packaging are explored. Sustainable packaging can stimulate economic growth and offer new opportunities for companies, notably by helping the environment and reducing the carbon footprint. However, the cost of sustainable packaging can still be challenging for small businesses. Determining whether consumers are willing to pay more for sustainable packaging is also crucial in this transition. © 2024 Sidas Medya A.S.. All rights reserved.
  • Öğe
    Optimization of bioethanol production from sugar beet processing by-product molasses using response surface methodology
    (Springer Science and Business Media Deutschland GmbH, 2025) Altınışık, Sinem; Nigiz, Filiz Uğur; Gürdal, Savaş; Yılmaz, Kadir; Tuncel, Necati Barış; Koyuncu, Sermet
    Bioethanol production from renewable biomass sources has garnered significant interest due to its potential as a sustainable alternative to fossil fuels. In this study, we investigated the optimization of bioethanol production from molasses, a by-product of the sugar production process using Saccharomyces cerevisiae through Response Surface Methodology (RSM). Initially, the fermentation process was optimized using RSM, considering four independent variables: substrate concentration, pH, temperature, and fermentation time. Subsequently, the effects of these variables on bioethanol yield were evaluated, and a quadratic model was developed to predict the optimum conditions. Analysis of variance (ANOVA) indicated a high coefficient of determination (R2) for the model, suggesting its adequacy for prediction. The optimized conditions for bioethanol production were determined as follows: substrate concentration of 200 g L−1, pH of 5.0, temperature of 30 °C and fermentation time of 72 h. Under these conditions, the predicted bioethanol yield was 84%. Overall, this study demonstrates the successful application of RSM for optimizing bioethanol production from molasses using S. cerevisiae, highlighting its potential as a promising feedstock for biofuel production. © The Author(s) 2024.
  • Öğe
    The Effect of Germination on Antinutritional Components, In Vitro Starch and Protein Digestibility, Content, and Bioaccessibility of Phenolics and Antioxidants of Some Pulses
    (John Wiley and Sons Inc, 2025) Yılmaz Tunçel, Neşe; Polat Kaya, Havva; Sakarya, Fatma Betül; Andaç, Ali Emre; Korkmaz, Fatma; Özkan, Gülay; Tuncel, Necati Barış
    The objective of this study was to investigate the impact of 24- and 48-h germination on antinutrient levels (phytic acid, trypsin inhibitors, saponins, and tannins), in vitro starch and protein digestibility, and the content and bioaccessibility of phenolic compounds and antioxidants in chickpeas, peas, mung beans, and lentils. Germination resulted in reductions of phytic acid by up to 75.65% and trypsin inhibitor activity by up to 39.20% in the pulses studied. In contrast, saponin levels showed a significant increase, rising nearly threefold with germination, while mung beans exhibited an exceptional 27-fold increase. Tannins decreased in lentils (2.6-fold) and mung beans (5.8-fold), increased in peas (1.6-fold), and remained unchanged in chickpeas following germination. In vitro protein digestibility generally increased with germination, reaching up to 4.40%, except in peas, where a decline was observed. Germination significantly enhanced total digestible starch content while reducing resistant starch in all pulses except chickpeas. Mung beans exhibited the highest total phenolic content and antioxidant capacity, followed by lentils. Although germination significantly elevated total phenolic content in all pulses, this increase did not always align with antioxidant capacity outcomes. Additionally, germination led to a decline in the bioaccessibility of phenolics. However, the amount of phenolic compounds progressively increased during gastric and intestinal digestion, with intestinal digestion further enhancing the total antioxidant capacity of the pulses. © 2025 The Author(s). Food Science & Nutrition published by Wiley Periodicals LLC.
  • Öğe
    The effect of simulated vibration frequency on the physico-mechanical and physicochemical properties of peach during transportation
    (Elsevier Ltd., 2021) Dağdelen, Çiğdem; Aday, Mehmet Seçkin
    Loss in fresh fruit and vegetables during transportation occurs mainly due to their susceptibility to mechanical damage. The quality loss caused by this damage depends on the shock and vibration frequencies. In this study, the effect of different vibration frequencies (5 Hz, 10 Hz, and 15 Hz) on the physico-mechanical and physico-chemical properties of peach was investigated. The parameters such as energy absorption, mechanical hysteresis, and deformation volume were increased whereas mean geometric diameter, surface area, volume, degree of elasticity, deformation energy, and modulus of elasticity were decreased. Regarding physicochemical properties, pH and total soluble solid parameters increased whereas lightness (L*) value of peach decreased. The highest level of damage and mold growth were observed on the peach treated with 15 Hz frequency followed by 10 Hz and 5 Hz, respectively. The effect of all the frequencies on the physico-mechanical and physico-chemical properties of peach was statistically different. The results indicated that the increase in the vibration frequency causes higher mechanical damage in peach.
  • Öğe
    Optimization of pretreatment and enzymatic hydrolysis conditions of tomato pomace for production of alcohols and esters by Kluyveromyces marxianus
    (Elsevier Ltd., 2021) Kılmanoğlu, Hilal; İşleten Hoşoğlu, Müge; Güneşer, Onur; Karagül-Yüceer, Yonca
    Tomato pomace (TP) is generated as a natural by product in a significant amount in the tomato processing industry, and it is a good source of lignocelluloses to produce some high-value products from fermentable sugars (FS). The present study was performed to produce FS by using either ultrasound-assisted dilute acid (UADA) or heat-treated dilute acid (HTDA) pretreatments of TP followed by enzymatic hydrolysis (EH). When HTDA and UADA were compared in terms of FS (g/L) concentration, HTDA pretreatment generally produced more FS content than UADA. The optimum conditions for HTDA pretreatment were the application of 2.5% H2SO4, 10% (w/v) solution of TP, and heating at 121 °C for 6 min, which yielded 31 g/L FS concentration. Beside the optimized conditions for EH of HTDA, pretreated TP required 1.5% of enzyme concentration and 6 h of hydrolysis time. In conclusion, the most abundant volatile organic compounds (VOCs) produced by K. marxianus in final tomato pomace hydrolysate (TPH) were isoamyl alcohol, phenyl ethyl alcohol, ethyl acetate and phenyl ethyl acetate in a 5-L bioreactor. Nine descriptive sensory terms were developed to characterize fermented TPH. The rose and sweet floral aromas were defined as aroma characteristics for TPH fermented by K. marxianus.
  • Öğe
    Soğuk Baskı Yöntemiyle Üretilmiş Greyfurt Çekirdek Yağındaki Acılığın Yıkama/Ekstraksiyon Teknikleriyle Giderilmesi
    (Sidas Medya A.S., 2021) Deviren, Ayten; Ok, Selçuk; Yılmaz, Emin
    In this study, different extraction and washing techniques used to remove the bitterness of grapefruit seed oil produced by cold pressing technique were compared. Some physico-chemical properties, oil components and sensory properties of the treated samples were determined. While the free fatty acidities of oils decreased with the treatments, there was a slight increase in the peroxide values of oils. As a result of the treatments, the ratio of total unsaturated fatty acids, tocopherol, and phytosterol concentrations decreased significantly (p<0.05). It is thought that these minor components, which have high nutritional value, leaked into the solvent phase. Naringin, which has a very bitter taste, was measured as 102.6 mg/kg in the control sample and reduced to 74.8 mg/kg by caustic washing and 32.3 mg/kg by extraction with ethanol. Similarly, neohesperidin, which has also a bitter taste, was completely removed from oils by these two treatments. Sensory score of bitterness was determined as 9.8 in the control sample, and it was reduced to 5.4 with caustic washing, and 2.6 with ethanol extraction. Similarly, raw vegetables, astringency, menthol and throat burning scores were also reduced with treatments. As a result, it was observed that the ethanol extraction technique was successful in removing the bitterness of oils.
  • Öğe
    MİKRODALGA DESTEKLİ HİDRODİSTİLASYON YÖNTEMİYLE ELDE EDİLEN PELARGONIUM GRAVEOLENS (ITIR) ESANSİYEL YAĞININ KARAKTERİSTİK BAZI ÖZELLİKLERİ
    (Gıda Teknolojisi Derneği, 2021) Aydınlık, Pelin; Karagül Yüceer, Yonca
    Bu çalışmada Pelargonium graveolens’den (ıtır) elde edilen esansiyel yağın karakteristik özellikleri incelenerek doğal katkı maddesi olarak elma suyunda kullanılabilirliği araştırılmıştır. Esansiyel yağ üretiminde mikrodalga destekli hidrodistilasyon yöntemi kullanılmış ve %1.75 verimle esansiyel yağ üretimi gerçekleştirilmiştir. Uçucu bileşenlerin tanımlanması amacıyla gaz kromatografisi kütle spektrometresi kullanılmıştır. Itır esansiyel yağının temel uçucu bileşenleri sitronelil format, izomenton, linalol, sitronelol ve geraniol olarak belirlenmiştir. Esansiyel yağın antioksidan aktivitesi 0.54 mM troloks/mL yağ bulunmuştur. Esansiyel yağın antibakteriyel etkisinin Escherichia coli’ye kıyasla Staphylococcus aureus üzerine daha fazla olduğu saptanmıştır. Itır esansiyel yağı ilave edilmiş elma suyunun mikrobiyel yükünde depolama boyunca düşüş olduğu belirlenmiştir. Ayrıca esansiyel yağ ilave edilen elma suyunun duyusal özellikler bakımından da kabul edilebilir olduğu tüketici testiyle ortaya koyulmuştur.
  • Öğe
    TİRE ÇAMUR PEYNİRİNİN BAZI FİZİKOKİMYASAL VE DUYUSAL ÖZELLİKLERİ
    (2021) Karaalioğlu, Onur; Günay, Ezgi; Karagül Yüceer, Yonca
    Bu çalışmanın amacı, İzmir’in Tire ilçesinde geleneksel olarak üretimi gerçekleştirilen Tire Çamur peyniri’nin bazı fizikokimyasal ve duyusal özelliklerinin belirlenmesidir. Bu çalışma kapsamında analizleri gerçekleştirilen Tire Çamur peyniri örnekleri arasında bileşim bakımından önemli farklılıklar olduğu saptanmıştır. Gaz kromatografisi-kütle spektrometrisi (GC-MS) vasıtasıyla gerçekleştirilen kromatografik analizlerde toplam 29 adet uçucu bileşen tespit edilmiştir. Duyusal değerlendirmeler sonucunda ise pişmiş, peynir altı suyu, kremamsı, fermente ve sütümsü yoğun olarak algılanan aromatikler olarak belirlenmiştir. Elde edilen veriler kapsamında, ürünün endüstriyel boyutlarda üretim standardizasyonunun sağlanmasıyla birlikte tüketiciler için ürünün kaynağını gösteren coğrafi işaret alınmasının; üreticiye, üretildiği bölgeye ve ülkemize önemli ekonomik katkı ve katma değer sağlama potansiyeline sahip olacağı düşünülmüştür.
  • Öğe
    Çanakkale bölgesinden alınan midye ve deniz suyu örneklerinin mikrobiyolojik kalitelerinin belirlenmesi
    (2021) Tosun, Melike Nur; Taylan Yalçın, Gizem; Zorba, Nükhet Nilüfer
    Bu çalışmada Çanakkale bölgesinde belirlenen 9 farklı istasyondan toplanan 536 midye örneğinin ve her istasyondan alınan deniz suyunun mikrobiyolojik kalitesi belirlenmiştir. Midye örneklerinin toplam mezofilik aerobik bakteri yükünün en yüksek Merkez İskele istasyonunda (3.56 log kob/g) olduğu belirlenmiştir. En yüksek E. coli varlığı ise Gelibolu istasyonunda (1.99 log kob/g) saptanmıştır. Midyelerin mikrobiyel yüklerinin toplandıkları istasyonlar arasında istatistiksel anlamda farklı olmadığı (P>0.05) görülmüştür. Midyelerin toplam mezofilik aerobik bakteri sayısı ile toplandıkları deniz suyunun toplam mezofilik aerobik bakteri sayısı arasında pozitif yönde korelasyon tespit edilmiştir (P<0.05). Gelibolu ve Lapseki istasyonlarındaki mikrobiyel yükün diğer istasyonlara göre daha yüksek olduğu saptanmıştır. Genel olarak değerlendirildiğinde Gelibolu ve Lapseki bölgesi haricinde Çanakkale boğazının farklı noktalarından alınan midyelerin mikrobiyel kalitesinin yasal sınırlar içerisinde olduğu belirlenmiştir.
  • Öğe
    Yayıkaltı içeceğinin fizikokimyasal ve duyusal özellikleri ile uçucu bileşenlerinin belirlenmesi
    (2021) Öğe, Çisem; Karagül Yüceer, Yonca
    Bu çalışmada yayıkaltı suyunun farklı mikroorganizmalarla fermantasyonu ile üretilen içeceklerin karakteristik bazı özelliklerinin belirlenmesi amaçlanmıştır. Toz halindeki yayıkaltının %10’luk çözeltisi ile belirli oranlarda (% 0, 25, 50, 75, 100) çiğ süt karışımına ısıl işlem uygulandıktan sonra örneklere L. acidophilus (LA) kültürü ve L. acidophilus, Bifidobacteria ile S. thermophilus karışık kültürü (ABT) ilave edilerek 37°C’de, yaklaşık 4.8 pH’ya kadar inkübe edilmiştir. Ürünlerin fizikokimyasal ve duyusal özellikleri ve uçucu bileşenleri depolama süresince belirlenmiştir. İçeceklerde yayıkaltı suyu oranı azaldıkça yağ, kurumadde ve protein oranları artmıştır. Örneklerde uçucu bileşenler gaz kromatografisi kütle spektrometrisi kullanılarak belirlenmiştir. Tüm örneklerde belirlenen uçucu bileşikler aseton, 2,3-butandion, asetoin, toluen, 2-heptanon, limonen, ökaliptol, asetik asit ve butanoik asit olmuştur. Yayıkaltı içeceklerinde pişmiş, kremamsı, süthane/sütümsü, fermente, karton, yosun, sabunsu, depo, tatlı, tuzlu, buruk ve acı terimleri duyusal değerlendirmeler sonucunda belirlenmiştir.
  • Öğe
    Kitosan bazlı etil pirüvat filmlerin fizikokimyasal, antioksidan, antimikrobiyal ve anti-quorum sensing özelliklerinin belirlenmesi
    (2021) Kaya, Burcu; Zorba, Nükhet Nilüfer; Caner, Cengiz
    Bu çalışmada kitosan film formülasyonuna iki farklı (%1 ve %3) konsantrasyonda etil pirüvat ilave edilerek, çevre dostu bir ambalaj materyali geliştirilmesi amaçlanmıştır. Bu kapsamda hazırlanan film örneklerinin nem, suda çözünürlük, görünür yoğunluk, renk, biyobozunurluk, kimyasallara karşı direnç özellikleri belirlenerek, filmlerin yüzey morfolojisi SEM, fonksiyonel grupları ise FTIR ile karakterize edilmiştir. Ayrıca film örneklerinin antimikrobiyal ve anti-quorum sensing aktivitesi disk difüzyon yöntemi ile belirlenmiştir. Sonuç olarak formülasyona etil pirüvat eklenmesiyle kitosan filmin nem içeriği, görünür yoğunluğu, biyobozunurluğu ve antioksidan aktivitesi artmıştır. SEM görüntüleri incelendiğinde ise etil pirüvatın, kitosan filmlerde gözenekli yapı oluşumuna neden olduğu gözlemlenmiştir. Film örnekleri Escherichia coli O157:H7, Bacillus cereus, Staphyloccocus aureus, Alternaria arborescens, Aspergillus flavus, Penicillium digitatum, Penicillium citrinum ve Penicillum expansum suşlarına karşı antimikrobiyal etki göstermiştir. Buna ek olarak tüm film örneklerinin anti-quorum sensing aktivite gösterdiği tespit edilmiştir. Elde edilen verilere göre özellikle CS-EP1 filminin, doğa dostu alternatif gıda ambalajı olarak kullanılabileceği belirlenmiştir.
  • Öğe
    Characterization of aroma-active compounds, sensory properties, and proteolysis in Ezine cheese
    (Elsevier Science Inc, 2009) Karagül Yüceer, Yonca; Tuncel, Barış; Güneşer, Onur; Engin, Burcu; İşleten, Müge; Yaşar, Kurban; Mendeş, Mehmet
    Ezine cheese is a white pickled cheese ripened in tin-plate containers for at least 8 mo. A mixture of milk from goat, sheep, and cow is used to make Ezine cheese. Ezine cheese has geographical indication status. The purposes of this study were to determine and compare the changes in basic composition, aroma, and sensory characteristics, and proteolytic activity of Ezine cheese stored in tinplate containers and plastic vacuum packages during storage. Aroma-active compounds were determined by thermal desorption gas chromatography olfactometry. To evaluate the proteolytic activity, casein and nitrogen fractions were determined. The results indicated that compounds identified at high intensities were dimethyl sulfide, ethyl butyrate, hexanal, ethyl pentanoate, (Z)-4-heptenal, 1-octen-3-one, acetic acid, butyric acid, and p-cresol. Characteristic descriptive terms were cooked, whey, creamy, animal-like, sour, and salty. The level of proteolysis increased in Ezine cheese during storage. Ezine cheese can be ripened in small-size packaging after 3 mo of storage. Approximately 6 mo is sufficient to produce the characteristic properties of Ezine cheese.
  • Öğe
    Sensory characteristics of Ezine cheese
    (Wiley, 2007) Karagül Yüceer, Yonca; İşleten, Müge; Uysal Pala, Çiğdem
    Ezine cheese is a full-fat, white pickled cheese ripened in tinplate containers. A mixture of milks from goat, sheep and cow is used to make Ezine cheese. It has its own characteristic taste and aroma that differ from other white cheeses. In this study, the chemical composition and sensory attributes of Ezine cheese were characterized. A descriptive sensory evaluation technique was used to determine flavor and texture characteristics. Representative Ezine cheeses (22) were provided by local producers. A highly trained (n = 9) panel generated the descriptive terms and identified the references. Fourteen flavors and 10 texture terms were developed to describe Ezine cheese flavor and texture. Some characteristic flavor and taste descriptors for Ezine cheese were free fatty acids, cooked, creamy, whey-like, goaty, salty and sour. Cheese texture was evaluated using hand, mouth and residual techniques. Texture analysis indicated that Ezine cheese had soft and semi-hard texture properties. In general, most of the Ezine cheeses showed similarities in terms of hand firmness, mouth firmness, fracturability and number of particles attributes.
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    Comparative analysis of essential oil oleogels containing beeswax and sunflower wax with petrolatum gels
    (Wiley, 2024) Çokay, Hatice; Çelebi Uzkuç, N. Merve; Karagül Yüceer, Yonca; Öğütcü, Mustafa
    In this study, three different oil (black seed, St. John's Wort, and grape seed oils [GSO]) oleogels, which are especially used in complementary medicine, were produced with natural waxes (sunflower and beeswax [BW]). The physicochemical, textural, thermal, and structural features and volatile composition of the oleogels were determined and compared with commercial petrolatum gels (control sample). The sunflower and BW gels had a higher melting point than the petrolatum gels. Particularly, the firmness values of the fresh sunflower and BW oleogels were close to the petrolatum gels, except for the BW-based St John's Wort and GSO gels. The firmness and stickiness values of the oleogels and the control samples increased in relation to the storage period. The increase in firmness value was less in the sunflower wax than in the BW and control samples. All sunflower, BW and petrolatum gels exhibited the beta ' form. Volatile component data showed that different waxes have different volatile adsorption capacities. As a result, natural wax oleogels produced with various essential oils could be an alternative to similar products used in the cosmetics, pharmacology, and food supplement industries, which are already commercially available.Practical applications: (Oleogels have become a popular technique for structuring oils in recent years. In this way, oleogels are considered an alternative to solid fat such as margarine, butter, and shortening and an oil-restricting agent against oil leakage in oil-based foods. Consumers establish a close relationship between their own health and the foods they consume and the cosmetics they use. This situation has led to an increasing interest in natural products. Essential oils (EOs) are used in many fields, ranging from cosmetics to complementary medicine. In this context, essential oleogels produced with natural waxes were compared with the commercial products, revealing their potential for use in both cosmetic and food supplements. EO-oleogels represent a new approach to the oleogel product range with high commercialization potential for related industries.) Graphical Abstract: The textural and structural properties of the essential oil oleogels prepared with beeswax and sunflower wax were almost similar to their commercial counterparts such as petrolatum. image