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    Article
    Citation - WoS: 11
    Citation - Scopus: 15
    Effects of Extrusion Cooking on the Nutritional Quality of Puffed Snacks Made From Blends of Barley and Green Lentil Flours
    (Springer, 2023) Li, Xiang; Franczyk, Adam; Kahraman, Kevser; House, James D.; Koksel, Filiz
    Increasing demand for nutritionally dense foods warrants the investigation of high fiber and protein ingredients in snack food applications. In this study, blends of barley (22.9% dietary fiber, db) and green lentil (26.4% protein, db) flours were extruded at five blending ratios (barley: green lentil, 100: 0, 75: 25, 60: 40, 45: 55, 0: 100, db), two barrel temperature profiles (60-130 degrees C and 70-140 degrees C from feeder to die) and three feed moisture contents (15, 18 and 21%) to produce puffed snacks. Extrusion significantly improved in vitro protein digestibility (IVPD) of all blends by up to 10%. Decreasing feed moisture and increasing die temperature improved IVPD. Blending increased the limiting amino acid score and hence improved the in vitro protein digestibility corrected amino acid score (IVPDCAAS) of extrudates. On average, the blend 45:55 showed the highest average IVPDCAAS (68.62%) among the blends studied and lower glycemic index scores compared to the blend 60: 40. In general, extrusion did not substantially affect the soluble, insoluble or total dietary fiber contents of the blends. All extrudates from blends 60: 40 and 45:55 met the requirement to be labelled as "good source of dietary fiber" in the US.
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    Article
    Citation - WoS: 7
    Citation - Scopus: 7
    Production of Oven-Baked Wheat Chips Enriched With Red Lentil: An Optimization Study by Response Surface Methodology
    (Springer India, 2022) Babacan Cevik, Selin; Kahraman, Kevser; Ekici, Lutfiye
    Chips are the most common snacks in human diet and generally are produced by frying. However, due to their high carbohydrate, fat and salt content, they are considered as unhealthy snacks. In this study, it is aimed to develop red lentil enriched chips for use as a healthy and nutritious snack food. Due to the health concerns about high fat content of the fried chips, the samples were oven-baked instead of frying. Response surface methodology was used to investigate the effect of process parameters (red lentil flour ratio, baking temperature and time) on physicochemical, textural, nutritional, and bioactive properties of the chips. The samples were also evaluated in terms of taste, odor, crispness, and general acceptance by the panelists. The highest antioxidant capacity, total phenolic content and hydroxymethyl furfural content was achived with the sample supplememented with 50% red lentil flour and baked at the highest temperature and time used in the study (190 degrees C, 9 min). Red lentil flour supplementation increased protein and resistant starch content of the chips. The highest resistant starch content of the samples and lowest in vitro glycemic index value were achieved with the sample prepared with 50% red lentil flour supplementation. These results of this study proved that red lentil is a good source to be used for enrichment of oven-baked wheat chips as a novel snack food with high nutritional values and low in vitro glycemic index.
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    Citation - WoS: 1
    Citation - Scopus: 1
    A Functional Barley-Based Fermented Soup (Tarhana) With High Β-Glucan Content
    (Springer, 2025) Koksel, Hamit; Ozkan, Kubra; Tekin-Cakmak, Zeynep Hazal; Karasu, Salih; Kahraman, Kevser; Oruc, Sena; Sestili, Francesco
    This study investigates the impact of using different flours, including high beta-glucan barley, on the nutritional properties of tarhana. Mineral composition, phenolic content, and antioxidant capacity of tarhana powder samples produced using flours of high beta-glucan hull-less barley (cv. Chifaa; ChF), hull-less barley cv. Yalin (YF), bread wheat cv. Tosunbey (white flour: TWF1 and whole wheat flour: TWF2). Furthermore, in vitro glycemic index (GI), pasting properties, and RVA soup index of their soups were investigated. Tarhana made with Chifaa barley flour (Tar-ChF) exhibited significantly higher levels of key minerals (K, Mg, Ca), beta-glucan and total phenolic content compared to those made with other flours (Tar YF, Tar TWF1, and Tar TWF2). Barley tarhana samples also showed greater antioxidant activity of bound phenolic fractions and lower GI values, indicating a healthier profile. The study highlights the potential of high beta-glucan barley flour to enhance tarhana's nutritional benefits without significantly affecting its sensory properties, such as color and viscosity. This research supports the integration of health-promoting ingredients like barley flour into traditional Mediterranean foods to improve their nutritional quality.
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    Article
    Buckwheat Starch–Myristic Acid Complex Formation: Effect of Reaction Temperature and Myristic Acid Concentration on Digestibility Properties
    (2022) Aydemir, Levent Yurdaer; Ozbey, Ayse; Kahraman, Kevser; Emlek, Betül Oskaybaş
    Bu çalışma, farklı miristik asit konsantrasyonları ve farklı reaksiyon sıcaklıkları kullanılarak üretilen karabuğday nişastası-miristik asit kompleksi örneklerinin sindirilebilirlik özellikleri üzerine farklı reaksiyon koşullarının etkisini araştırmayı amaçlamıştır. Reaksiyon sıcaklığının (60-90°C) ve yağ asidi konsantrasyonlarının (0.1-0.8 mmoL/g) sindirilebilirlik özellikleri üzerindeki etkisini araştırmak için Yanıt Yüzey Metodolojisi kullanılmıştır. Örneklerin enzime dirençli nişasta (EDN) içerikleri reaksiyon sıcaklığındaki artışla artmıştır. Reaksiyon sıcaklığı, örneklerin hızlı ve yavaş sindirilebilir nişasta içeriklerini etkilemiştir. En yüksek EDN içeriği (%32.57) 90°C'de 0.45 mmoL/g miristik asit kullanılarak üretilen örnekte elde edilmiştir. F, p (<0.05) ve R2 değerleri seçilen modellerin numunelerin sindirilebilirlik özellikleri için önemli olduğunu göstermiştir. Karabuğday nişastasının miristik asit ile kompleks oluşturması, EDN içeriğini artırma konusunda umut verici görünmektedir. Karabuğday, çalışmalar henüz oldukça yeni olmasına rağmen, EDN kaynağı olarak önemli bir potansiyele sahip görünmektedir.
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    Article
    PSF/SiO2 Nanokompozit Membran Üretimi ve Elma Suyu Berraklaştırma Prosesinde Kullanımı
    (2019) Kahraman, Kevser; Severcan, Solmaz Şebnem; Uzal, Nıgmet
    Bu çalışmada faz dönüşümü yöntemi kullanılarak üretilen PSF/PEI (%20/2, w/w) membranlar, farklıkonsantrasyonlarda SiO2 nanopartikülü (%0,01; 0.03; 0.05) kullanılarak modifiye edilmiş ve üretilennanokompozit membranların bulanık elma suyunun berraklaştırılmasında performansları değerlendirilmiştir.Membran deneyleri sonlu filtrasyon sistemi kullanılarak gerçekleştirilmiştir. Üretilen yeni nesil nanokompozitmembranlar saf su akı değerleri, SEM ve yüzey temas açı değerleri açısından karakterize edilmiştir. Aynı zamanda,üretilen PSF/PEI/SiO2 yeni nesil nanokompozit membrandan elde edilen berrak elma suyu örnekleri renk (PtCo), bulanıklık(NTU) ve toplam suda çözünür kuru madde bakımından karakterize edilmiştir ve Döhler GıdaSan. A.Ş.’den temin edilen berrak elma suyu örnekleri (Brix) ile bu parametreler açısından karşılaştırılmıştır. Eldeedilen sonuçlara göre %0,01 oranında SiO2 ilave edilerek üretilen PSF/PEI/SiO2 membranın en yüksek saf suakısına ve en yüksek hidrofilikliğe sahip olduğu belirlenmiştir. Aynı zamanda bu membrandan elde edilen berrakmeyve suyu örneği en yüksek renk ve toplam suda çözünür kuru madde sahipken aynı zamanda en düşükbulanıklık değeri ile elma suyu berraklaştırma deneylerinde de en iyi performansı sergilemiştir.
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    Master Thesis
    Yeni Nesil Membran Üretimi ve Meyve Suyu Endüstrisinde Uygulamaları
    (Abdullah Gül Üniversitesi, 2018) SEVERCAN, SOLMAZ ŞEBNEM; Severcan, Solmaz Şebnem; Kahraman, Kevser; Uzal, Niğmet
    Gıda endüstrisinde kullanılan membran ayırma süreçleri, geleneksel yöntemlerle kıyaslandığında; işletim süresini ve maaliyeti azaltma ve aynı zaman da ürünün besinsel bileşenlerini ve duyusal karakterini koruma gibi önemli avantajlara sahiptir. UF membranlar, bulanıklığa neden olan, askıdaki proteinler, yağ ve polisakkaritler gibi büyük molekülleri gidererek berraklaştıma sağlamak için kullanılırlar. UF membranlar, uygun maaliyet, yüksek film oluşturma özelliği, üstün kimyasal ve termal direnç gibi birçok avantaja sahip olmasına rağmen, tıkanma problemi en büyük dezavantajıdır. Bu sorunun üstesinden gelmek için, bir çok araştırmacı membran hidrofilikliğni ve tıkanma direncini artırmak için membran modifikasyonu üzerine çalışmışlardır. Bu çalışmada, membranın yapısal ve morfolojik özelliklerini değiştirmek için, PSF/PEI (20%/2%) UF ve PSF/PEI (17%/2%) MF membranlara farklı konsantrasyonlarda (0.01, 0.03, 0.05 %) TiO2 and Al2O3 nanoparçacıları eklenerek, faz dönüşümü yöntemi ile nanokompozit membranlar hazırlanmıştır. Döhler Gıda San. ve Tic. Ltd. Şti.(Karaman, Türkiye) firmasından temin edilen elma ve nar suyu pulp örnekleri, sırasıyla çapraz akış filtrasyon sistemi ve sonlu filtrasyon sitemi 5.4 bar da işletilerek, berraklaştırılmıştır. Üretilen yeni nesil nanokompozit membranlar, taramalı elektron mikroskobu (SEM), Fourier dönüşümlü kızılötesi spekrometre (FT-IR), temas açısı, gözeneklilik ve saf su akısı ölçümleri ile karakterize edilmiştir. Ayrıca, üretilen nanokompozit membranların tıkanma direç performansının tayini için, akı geri kazanım oranı (FRR), saf su akı azalma oranı (DR) ve bağıl akı azalma oranı (RFR) hesaplanmıştır. Bunlara ek olarak, elde edilen berrak elma ve nar suyu renk, bulanıklık, toplam çözünmüş madde, toplam antioksidan aktivitesi (ABTS radikal yakalama metodu ve DPPH radikal yakalama metodu) ve toplam fenolik madde analizleri ile karakterize edilmiştir. Ayrıca, berrak nar suyu için toplam monomerik antosiyanin tayini yapılmıştır. Üretilen nanokompozit membranlar kullanılarak elde edilen berrak meyve suyu analiz sonuçları, firmadan temin edilen berrak meyve suları ile karşılaştırılmıştır. Membran ve meyve suyu karakterizasyon sonuçları, üretilen yeni nesil nanokompozit membranların, elma ve nar suyu berraklaştırmasında etkili bir şekilde kullanılabileceğini göstermiştir. Üretilen nanokompozit membranlar arasında %0.01 TiO2 eklenen PSF/PEI UF membran ve %0.05 Al2O3 eklenen PSF/PEI MF membranlar, sırasıyla elma ve nar suyu berraklaştırması açısından üstün performans göstermiştir.
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    Article
    Citation - WoS: 46
    Citation - Scopus: 54
    Effect of Different Resistant Starch Sources and Wheat Bran on Dietary Fibre Content and in Vitro Glycaemic Index Values of Cookies
    (Academic Press Ltd- Elsevier Science Ltd, 2019) Kahraman, Kevser; Aktas-Akyildiz, Eda; Ozturk, Serpil; Koksel, Hamit
    Cross-linked starches produced in lab-scale from corn and wheat starches with TDF contents of 80.4% and 83.6% were used in cookie formulation to obtain high fibre and low glycaemic index (GI) cookies. Different resistant starch (RS) sources including and wheat bran were also used for comparison. RS sources were added into the formulation at the levels of 25, 50 and 75%. Overall cookie quality (spread ratio, hardness, colour) results showed that among the RS sources and wheat bran, lab-scale produced cross-linked wheat starch (XL-W) had an improving effect on cookie quality, whereas the other sources had detrimental effect. Cookie samples supplemented with XL-W had the highest total dietary fibre (TDF) contents regardless of the addition level. High levels of TDF content were also observed with the wheat bran supplemented cookie samples; however, quality of these cookies were low. RS and wheat bran supplementation caused significant decrease in the in vitro GI of the cookies and the lowest GI value was achieved with the cookie supplemented with XL-W. This study proved that XL-W produced in this study can be used as an alternative ingredient to produce high fibre and low GI cookies without any deteriorative effect on the quality.
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    Article
    Development and Characterization of Starch-Fatty Acid Complexes Produced with Buckwheat Starch and Capric/Stearic Acid Using Different Reaction Conditions
    (Elsevier, 2025) Oskaybas-Emlek, Betul; Ozbey, Ayse; Aydemir, Levent Yurdaer; Kahraman, Kevser
    The aim of present study was to investigate the impact of reaction parameters on the complex formation between buckwheat starch and capric acid (B-Capric) or stearic acid (B-Stearic). The most effective parameters on complex formation indicator (Complex index (CI) value) were found as reaction temperature (60-90 degrees C) and pH (5-8). Additionally, the effect of these parameters on physicochemical, pasting, and in-vitro digestibility properties of complex samples were evaluated. XRD and FTIR was also used in characterize the complex samples. In general, increasing pH increased the CI values of B-Stearic samples while decreasing those of B-Capric samples. Syneresis of buckwheat starch increased after complexation while paste clarity and swelling power diminished. The pasting properties of native starch significantly changed after complex formation. The FTIR results showed that starch structure changed with complex formation. XRD revealed that buckwheat starch, having an A-type pattern, converted to V-type pattern after complexation. Complex formation of buckwheat starch with capric and stearic acid significantly increased the RS content of buckwheat starch (19.01 %) by up to 36.25 % and 30.60 %, respectively. These results highlight the possibility of using buckwheat starch-capric acid/stearic acid complexes in food formulation to enhance the RS content.
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    Book Part
    Dietary Fibers
    (Springer Nature, 2021) Drǎgan, Simona Ruxandra; Damian, Georgiana; Pah, Ana Maria; Hayta, Mehmet; Kahraman, Kevser
    Dietary fibers have become increasingly popular in recent years with various applications in the food and pharmaceutical industry industries. Dietary fibers are plant-based foods which are incompletely digested by digestive enzymes. The water-soluble fibers are prebiotics, which are fermented in the colon and have a beneficial role for gut microbiota. The insoluble fibers are not affected by digestive systems and provide bulking. Fiber intake has various benefits: it reduces appetite, lowers variance in blood sugar levels, reduces the risk of cardiovascular disease, lowers the risk of diabetes, balances intestinal pH, alle¬viates constipation, and facilitates regular defecation. © 2023 Elsevier B.V., All rights reserved.
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    Article
    Citation - WoS: 4
    Citation - Scopus: 4
    Development of Buckwheat Starch-Capric Acid Complex-Based Film: Process Optimization and Film Characterization
    (Wiley-VCH Verlag GmbH, 2025) Koca, Esra; Kahraman, Kevser; Oskaybas-Emlek, Betul; Ozbey, Ayse; Aydemir, Levent Yurdaer
    To overcome the limitations of starch usage alone, the film formation ability of the buckwheat starch-capric acid complex (BS-CA) was optimized, and the films were characterized. Significant models were obtained for tensile strength (TS) and Young's modulus (YM) of BS-CA film (p < 0.0001). The glycerol/starch ratio, temperature, and their interactions were significant in the YM model (R-2 is 0.9851). The BS-CA film had a better water vapor barrier (0.463 +/- 0.02 g mm/m(2) h kPa), with lower water solubility (WS) (34.18 +/- 1.70%) and moisture content (MC) (16.87 +/- 0.09%) than the buckwheat starch (BS) film (p < 0.05). It had lower thickness (0.073 +/- 0.00 mm) and TS (0.624 +/- 0.04 MPa) but higher elasticity (114.60 +/- 3.12%). The non-covalent interactions were determined between BS and CA, since new peaks were not observed in the film's FTIR spectrum. BS-CA film had a typical V-type crystalline structure and had slightly lower decomposition temperatures than the BS film. Contact angle measurements (55.19 degrees +/- 1.7), and images of AFM topography and SEM showed that the BS-CA film surface was hydrophilic; height and average roughness values were 1014 and 276 nm, respectively, which were quite higher than those of BS film. The results reveal that starch modification with fatty acid is a promising way to develop starch-based films to be used in practical applications.
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    Article
    Citation - WoS: 19
    Citation - Scopus: 26
    Production of Buckwheat Starch-Myristic Acid Complexes and Effect of Reaction Conditions on the Physicochemical Properties, X-Ray Pattern and FT-IR Spectra
    (Elsevier, 2022) Oskaybas-Emlek, Betul; Ozbey, Ayse; Aydemir, Levent Yurdaer; Kahraman, Kevser
    In this study, the effect of reaction parameters on complex index (CI%) value of complexes formed between buckwheat starch (BS) and myristic acid (MA) was investigated. The temperature (60-90 ?C) and MA to BS ratio (0.1-0.8 mmoL/g) were determined as the most effective parameters and their effect on CI% was evaluated using response surface methodology. The MA to BS ratio, temperature, and interaction between them had an influence on CI%. The CI% of BS-MA complexes increased with increasing MA ratio until a certain level of MA. Principal component analysis (PCA) was used for correlation analysis between parameters. Swelling power and paste clarity of BS decreased with complex formation while syneresis increased. Peak and final viscosity values of the BS-MA complexes were significantly lower than those of BS. FT-IR revealed the complex formation led to change in starch structure. The XRD confirmed the BS-MA complex formation but the BS-MA produced using 0.1 mmoL/ g at 60 ?C was not detected by XRD due to having low crystallinity, and expectedly, the lowest relative crystallinity value was achieved with this sample among complex samples. All results showed that the buckwheat be an alternative starch source for starch formation.
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    Article
    Citation - WoS: 29
    Citation - Scopus: 41
    Optimisation of the Reaction Conditions for the Production of Cross-Linked Starch With High Resistant Starch Content
    (Elsevier Sci Ltd, 2015) Kahraman, Kevser; Koksel, Hamit; Ng, Perry K. W.
    The optimum reaction conditions (temperature and pH) for the preparation of cross-linked (CL) corn and wheat starches with maximum resistant starch (RS) content were investigated by using response surface methodology (RSM). According to the preliminary results, five levels were selected for reaction temperature (38-70 degrees C) and pH (10-12) in the main study. RS contents of the CL corn and wheat starch samples increased with increasing temperature and pH, and pH had a greater influence on RS content than had temperature. The maximum RS content (with a maximum p value of 0.4%) was obtained in wheat starch cross-linked at 38 degrees C and pH 12. In the case of CL corn starch, the optimum condition was 70 degrees C and pH 12. CL corn and wheat starch samples were also produced separately under the optimum conditions and their RS contents were 80.4% and 83.9%, respectively. These results were also in agreement with the values predicted by RSM. (C) 2014 Elsevier Ltd. All rights reserved.
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    Article
    Citation - WoS: 17
    Citation - Scopus: 24
    Quality, Nutritional Properties, and Glycemic Index of Colored Whole Wheat Breads
    (MDPI, 2023) Koksel, Hamit; Cetiner, Buket; Shamanin, Vladimir P.; Tekin-Cakmak, Z. Hazal; Pototskaya, Inna V.; Kahraman, Kevser; Morgounov, Alexey I.
    The main aim of this study was to investigate the quality and nutritional properties (dietary fiber, phenolic, antioxidant contents, and glycemic index) of breads made from whole wheat flours of colored wheats. White (cultivar Agronomicheskaya 5), red (Element 22), purple (EF 22 and Purple 8), and blue (Blue 10) colored wheats were used in the study. The whole wheat flours of Blue 10 and Purple 8 had higher farinograph stability, lower softening degree, and higher quality numbers indicating that they had better rheological properties. Bread produced from whole wheat flour of blue-colored grain had significantly higher loaf volume and better symmetry, crust color, crumb cell structure, and softness values among others (p < 0.05). The whole wheat bread produced using Element 22 had the highest crust and crumb L* color values, while Purple 8 and EF 22 had the lowest crust and crumb L* color values, suggesting that purple-colored grains have a tendency to make whole wheat bread with darker crust and crumb color. Bread produced from cultivar Blue 10 had the lowest firmness values while Element 22 had the highest firmness values. The highest total phenolic content and antioxidant capacity values were obtained from the whole wheat bread sample from purple-colored wheat (Purple 8). The whole wheat flour of Element 22 had the highest total dietary fiber content among all samples (p < 0.05). The differences between whole wheat bread samples in terms of total dietary fiber and glycemic index were not statistically significant. The results of the present study indicated that colored wheats can be used to produce whole wheat breads with higher nutritional properties and acceptable quality characteristics.
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    Article
    Citation - Scopus: 18
    Characterization of Local Sorghum (Sorghum Bicolor L.) Population Grains in Terms of Nutritional Properties and Evaluation by GT Biplot Approach
    (Wiley-VCH Verlag info@wiley-vch.de, 2020) Kaplan, Mahmut; Kale, Hasan; Kardeş, Yusuf Murat; Karaman, Kevser; Kahraman, Kevser; Yilmaz, Mehmet Fatih; Akar, Taner
    This study is conducted to characterize some nutritional attributes and starch properties of 156 Turkish sorghum populations and 4 standard cultivars (Sorghum bicolor L.). Crude protein contents of the populations vary between 6.67% and 14.33%, digestible protein ratios between 6.67% and 82.24%, crude oil contents between 2.15% and 6.40%, phytic acid contents between 0.37% and 4.09%, resistant starch between 1.10% and 34.23%, nonresistant starch between 10.79% and 79.61%, total starch between 15.42% and 85.54%, amylose between 5.67% and 43.48%, amylopectin between 9.45% and 65.67%, total phenolic between 0.19% and 5.06 mg GAE/g and antiradical activity between 3.72% and 91.48%. Significant differences are obtained from starch-based Rapid Visco Analyzer parameters of sorghum genotypes. As compared standard cultivars, several superior genotypes are identified in terms of nutritional characteristics. Genotype treatment (GT) biplot analysis revealed ideal genotypes for investigated parameters. Present findings confirmed that there are many genotypes with superior nutritional properties in local sorghum genotypes. © 2020 Elsevier B.V., All rights reserved.
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    Master Thesis
    Omega-3 Yağ Asitlerinin Nişasta Nanopartiküllerle Stabilize Edilmiş Emülsiyonlar İçine Enkapsüle Edilmesi
    (Abdullah Gül Üniversitesi, Fen Bilimleri Enstitüsü, 2021) Korkut, Ayşe; Kahraman, Kevser
    Bu tez çalışmasının temel amacı emülsiyon stabilizatörü olarak kullanılacak nişasta nanopartiküllerini üretmektir. Tezin ilk bölümünde asit hidrolizi ile nişasta nanopartikülleri üretilmiş ve nişasta nanopartikülleri morfolojik özellikler ve boyut, kristalinite ve yapısal özellikler açısından karakterize edilmiştir. Pickering emülsiyonlar, iki farklı yağ fraksiyonunda (Φ0.6 ve Φ0.8) ve farklı yağlarla (ayçiçeği ve mısır yağı) hazırlanmıştır. En iyi emülsiyon stabilitesini sağlayan nişasta nanopartikülünü belirlemek için emülsiyonlar %2 nişasta nanopartikülü (mg nişasta/g emülsiyon) ilavesiyle hazırlanmıştır. Emülsiyonlar, oda koşullarında 30 gün süreyle depolanmış ve faz ayrımı olup olmadığı gözlenmiştir. En stabil emülsiyon, Φ0.6 yağ fraksiyonunda mısır yağı ile 1:3 nişasta:H2SO4 oranı (1:3 (3)) ile 3 gün hidrolize edilmiş nişasta nanopartikülü (%2) kullanılarak hazırlanmıştır. Tezin ikinci bölümünde, omega-3 yağ asitleri Pickering emülsiyonlar içine enkapsüle edilmiştir. Omega-3 kaynağı olarak keten tohumu yağı seçilmiştir. Emülsiyonlar, %3 oranında nişasta nanopartikülleri (1:3(3)) ilavesiyle Φ0.2 yağ fraksiyonunda hazırlanmıştır. Emülsiyonlar 25±1°C' de 15 gün depolanmış ve depolama sırasında emülsiyonlardaki değişiklikler fiziksel stabilite, peroksit sayısı, pH, partikül boyutu ve zeta potansiyeli açısından incelenmiştir. Omega-3 yağ asitlerinin enkapsüle edilmesi için kullanılan nişasta nanopartikülleri ile stabilize edilen Pickering emülsiyonlar, keten tohumu yağını birincil oksidasyona karşı daha dirençli hale getirmiştir.
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    Book Part
    Ionizing Radiation
    (CRC Press, 2024) Braşoveanu, Mirela M.; Emlek, Betul Oskaybaş; Sabbaghi, Hassan; Kahraman, Kevser; Muti, Serpil Ozturk; Sher, Farooq; Nemţanu, Monica R.
    Ionizing radiation processing has demonstrated the potential to bring significant transformations in both the structure and functioning of starch. These modifications cover crucial features, including granular and molecular characteristics, pasting properties, rheological attributes, and gelatinization behavior. This comprehensive chapter aims mainly to provide a consolidated overview of the key findings that have been made recently about major alterations in the fundamental attributes of starch generated by diverse plant sources when exposed to ionizing radiation processing. Beyond articulating these modifications, the chapter explores other relevant topics, including analytical methods employed for characterizing irradiated starch, clarification of the radiation-induced reaction mechanism, and a discussion on safety considerations and regulatory frameworks associated with the utilization of ionizing radiation for treating starch within the context of food-related applications. Furthermore, based on all the highlighted elements, future research directions are proposed, with a focus on characterizing and defining the internal structure of irradiated starch, as well as exploring the functionalities of radiation-modified starches in both innovative and traditional food formulations. © 2024 Elsevier B.V., All rights reserved.
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    Book Part
    Citation - Scopus: 7
    Starch
    (Elsevier, 2023) Köksel, Hamit F.; Muti, Serpil Ozturk; Kahraman, Kevser
    Starch is the major source of carbohydrates in the human diet. It occurs in most plants in granules, which are usually between 1 and 100µm in diameter, depending on the plant source. Starch is the major component in cereals, comprising 60%-75% of the grain weight. Besides its nutritive value, starch is a valuable component because it affects the physical properties of foods. Different starches have characteristic features, varying in molecular structure, morphological properties, crystallinity, gelatinization and pasting, and enzyme digestibility. In recent years, modified starches and enzyme-resistant starches have also gained importance because of their functional benefits in foods. In addition, starch is an important industrial raw material in products like syrups, ethanol, textiles, and paper. This chapter explains the molecular structure of starch, its physical, physicochemical, and functional properties, as well as modified and resistant starches, focusing on the starches in cereal grains. © 2023 Elsevier B.V., All rights reserved.
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    Article
    Citation - WoS: 10
    Citation - Scopus: 14
    Modelling the Effects of Debranching and Microwave Irradiation Treatments on the Properties of High Amylose Corn Starch by Using Response Surface Methodology
    (Springer, 2018) Mutlu, Selime; Kahraman, Kevser; Severcan, Sebnem; Ozturk, Serpil
    Response surface methodology was applied to determine the effects of pullulanase debranching, microwave irradiation time (2-4 min) and power (20-100%) on resistant starch (RS) formation and in-vitro glycemic index (GI) values in high amylose corn starch, Hylon VII. Starch:water (1:10) suspensions were cooked and autoclaved, debranched with pullulanase (1000 PUN/g; 1500 U/kg starch) at 60 A degrees C and then different microwave-storing cycles and drying (oven or freeze drying) processes were applied. In order to describe the relationship between the dependent and independent variables (microwave power and irradiation time), the response values were fitted by first order polynomial regression models. Significance analysis showed that microwave irradiation time had significant effect on RS content and GI value of the samples treated with one cycle of microwave-storing prior to freeze-drying. Microwave power had significant factor on the GI value of the samples that were oven-dried after one cycle of microwave-storing. Solubility and water binding capacity values of all heat treated samples were higher than those of native starch. On the other hand, RVA viscosity values were lower than native starch for oven-dried samples. Water binding capacity, solubility and final viscosity values of the freeze-dried samples were higher than those of oven-dried ones.
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    Research Project
    Karabuğday Nişastasından Yenilebilir Film Üretimi ve Nişastanın Yağ Asitleri ile Modifikasyonunun Film Mekanik Özellikleri Üzerine Etkisi
    (TÜBİTAK, 2022) Kahraman, Kevser; Aydemir, Levent Yurdaer; Koca, Esra; Oskaybaş Emlek, Betül
    Bu proje, karabuğdaydan yüksek saflıkta ve verimde nişasta üretilmesini, üretilen nişastanın çeşitli yağ asitleri (10C, 14C, 18C) kullanılarak elde edilen amiloz-lipit kompleksinden film üretimini amaçlamaktadır. Amiloz-lipit kompleksi üretiminde herbir yağ asidi için en etkili iki reaksiyon parametresi (sıcaklık, süre, pH, yağ asidi/nişasta oranı) belirlenmiştir. Herbir yağ asidi için en etkili iki parametre kullanılarak merkezi kompozit tasarım ile deneme tasarımları oluşturulmuş, komplekslerin kompleks indeks (KI), görünür amiloz, sindirilebilirlik, su bağlama-çözünürlük, çirişlenme, berraklık ve sineresis derecesi gibi özellikleri açısından karakterize edilmiştir. Kompleks oluşumunun nişastanın yapısına etkisi XRD ve FT-IR ile incelenmiştir. Amiloz-lipit kompleks oluşumu ile nişastanın enzime dirençli nişasta miktarı artmış, şişme gücü azalmıştır. En yüksek KI değerine sahip amiloz-kompleksi içeren nişastalar kullanılarak gliserol varlığında filmler üretilmiştir. Gliserol konsantrasyonu, çözelti sıcaklığı ve pH?nın film mekanik özelliklerine etkisinin araştırılması amacıyla, bu parametreler kullanılarak yanıt yüzey yöntemi ile deneme tasarımları oluşturulmuş, film üretimi gerçekleştirilmiş ve optimum film karakteristiklerine sahip film üretiminin sağlandığı parametreler belirlenmiştir. Optimum koşullarda amiloz-lipit kompleksi kullanılarak üretilen filmlerin gerilme dirençleri miristik (1,09 MPa) ve stearik asit (3,360 MPa) için kontrol filme göre daha yüksek, uzama değeri ise kaprik asit (%114,59) için daha yüksek bulunmuştur. Amiloz-lipit kompleksi kullanılarak üretilen filmlerin çözünürlük, nem ve kalınlık değerleri kontrollere göre daha yüksek bulunmuştur. En iyi su buharı bariyer özelliğine amiloz-miristik asit kompleks filmi (0,394 g.mm/m2.h.kPa) ile elde edilmiştir. SEM ve AFM görüntüleri amiloz-lipit kompleksi kullanımının film morfolojik ve topografik özelliklerine etki ettiğini göstermiştir. Su ile yüzey temas açısı sonuçlarına göre sadece amiloz-stearik asit kompleksi filmi hidrofobik yüzeye sahip olmuşlardır. Tüm sonuçlar genel olarak değerlendirildiğinde proje kapsamında karabuğday nişastasından enzime dirençli nişasta kaynağı olma potansiyeline sahip amiloz-lipit kompleksi oluşturmuş; oluşturulan bu komplekslerden mekanik özellikleri yüksek yenilebilir film üretimi gerçekleştirilebilmiştir.
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    Article
    Citation - WoS: 20
    Citation - Scopus: 21
    Effects of Resistant Starch Type 4 Supplementation of Bread on in Vitro Glycemic Index Value, Bile Acid-Binding Capacity, and Mineral Bioavailability
    (Wiley, 2020) Aribas, Merve; Kahraman, Kevser; Koksel, Hamit
    Background and objectives RS4 is an alternative dietary fiber source with some potential physiological benefits giving better quality end products. Common dietary fiber sources including bran usually have deteriorative effect on color, textural properties, and consumer acceptability of breads. This study was designed to investigate the effect of RS4 supplementation on the bread quality as well as mineral bioavailability, bile acid-binding capacity, in vitro glycemic index. Findings Loaf volumes of the breads supplemented with RS4 were higher than the bread supplemented with wheat bran (WB). Among the bread samples, the one supplemented with WB had the darkest color and highest firmness values. During storage, WB supplementation caused the highest increase in bread firmness. RS4 supplementation caused higher total dietary fiber (TDF) and mineral bioavailability values and lower in vitro glycemic index than bran supplementation. Conclusions RS4 supplementation of bread caused increases in TDF content, bile acid-binding capacity, and mineral bioavailability and has less deteriorative effect on the quality than WB supplementation. Breads supplemented with WB had a faster staling rate than the breads supplemented with RS4. Significance and novelty Besides the better appearance and texture of the RS4 supplemented bread samples, the improvement in nutritional properties proved that RS4 is a better dietary fiber source than WB.
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