WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394
Browse
16 results
Search Results
Article Effects of Gelatinization Process on Some Physicochemical Parameters, Pasting Characteristics and Some Nutritional Properties of Pulsed Based Flour Blends(Springer, 2026-02-17) Kahraman, Kevser; Yuksel, Ferhat; Karaman, SafaIn this study, a flour mixture was composed by three different flours (wheat flour (WF), cranberry bean flour (CBF) and lentil flour (LF)) depending on a constructed mixture design and some physicochemical parameters, pasting characteristics and some nutritional properties were investigated before and after gelatinization process. The highest total dietary fiber content was determined for the sole cranberry bean flour. After gelatinization of the samples, total dietary fiber levels of the samples increased significantly, and it ranged between 4.70 and 25.16% for uncooked samples and 8.46-29.09% for cooked samples. Resistant starch (RS) content of the samples was also affected by the gelatinization process. Wheat flour showed an increase in the RS content after gelatinization process and similar increment in the RS content was observed for the sole lentil flour. Peak viscosity was the highest for the wheat flour (2318 cP) and lowest for the lentil flour (716.5 cP). Glycemic index of the cooked samples changed significantly, and it ranged between 94.4 and 123.5. This study showed that making flour composite and gelatinization process had a significant effect on the pasting properties and nutritional characteristics of the pulse-based flour mixture.Article Development and Characterization of Starch-Fatty Acid Complexes Produced with Buckwheat Starch and Capric/Stearic Acid Using Different Reaction Conditions(Elsevier, 2025-12) Oskaybas-Emlek, Betul; Ozbey, Ayse; Aydemir, Levent Yurdaer; Kahraman, KevserThe 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.Article Citation - WoS: 118Citation - Scopus: 140Resistant Starch Type V Formation in Brown Lentil (Lens Culinaris Medikus) Starch With Different Lipids/Fatty Acids(Elsevier Sci Ltd, 2018-02) Okumus, Bahar Nur; Tacer-Caba, Zeynep; Kahraman, Kevser; Nilufer-Erdil, DilaraThis study aimed to characterize the brown lentil (Lens culinaris Medikus) starch and investigate the formation of amylose-lipid complexes (Resistant Starch Type V) by the addition of different lipids/fatty acids (10%, w/w) to both raw and cooked starch samples. Resistant starch content (measured by the official method of AACCI (Method 32-40), using the resistant starch assay kit) of raw brown lentil starch (BLS) increased significantly by the additions of lipids/fatty acids, starch sample complexed with HSO (hydrogenated sunflower oil) (14.1 +/- 0.4%) being the highest. For the cooked starch/lipid complexes, more profound effect was evident (22.2-67.7%). Peak, breakdown and trough viscosity values of the amylose-lipid complexed starches were significantly lower than that of BLS (p < 0.05), while significant decreases in the setback and final viscosities were only detected in oil samples, but not in fatty acids. Each lipid in concern exerted different effects on the digestibility of starch and amylose-lipid complex formation while having no substantial differential effects on the thermal properties of starch depicted by differential scanning calorimetry (DSC). Amylose-lipid complex formation with suitable fatty acids/lipids seems a promising way of increasing resistant starch content of food formulations. Although the applications being quite uncommon yet, brown lentil seems to have potential both as a starch and also as a resistant starch source.Article Citation - WoS: 14Citation - Scopus: 16Production of Cross-Linked Resistant Starch From Tapioca Starch and Effect of Reaction Conditions on the Functional Properties, Morphology, X-Ray Pattern, Ft-Ir Spectra and Digestibility(Springer, 2021-01-02) Korkut, Ayse; Kahraman, KevserThe aim of this study was to investigate the effect of cross-linking temperature and pH on resistant starch (RS) formation as well as the functional, structural and morphology properties of tapioca starch. Tapioca starch was cross-linked using sodium trimetaphosphate (STMP) and sodium tripolyphosphate (STPP) at various temperature and pH. Increase in the reaction temperature and pH increased RS content and decreased swelling power (SP) of the samples. The sample cross-linked at 60 degrees C and pH 12 had the highest RS content (84.8%) and the lowest SP (3.0 g/g). The correlation coefficient between RS content and SP was 0.96. Cross-linking altered the pasting behavior significantly, while Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) patterns changed slightly. Cross-linking did not change the morphological structure and granular shape of the starch. In addition, cross-linked samples protect their original shapes during cooking and in vitro digestion probably since cross-linking restrict the water uptake and swelling due to the increase in the bonds within the molecule. Overall results proved that cross-linking at high temperature and high alkaline condition resulted in an increase in the RS content of tapioca starch.Article Citation - WoS: 25Citation - Scopus: 33Production of Buckwheat Starch-Myristic Acid Complexes and Effect of Reaction Conditions on the Physicochemical Properties, X-Ray Pattern and FT-IR Spectra(Elsevier, 2022-05) Oskaybas-Emlek, Betul; Ozbey, Ayse; Aydemir, Levent Yurdaer; Kahraman, KevserIn 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.Article Citation - WoS: 29Citation - Scopus: 41Optimisation of the Reaction Conditions for the Production of Cross-Linked Starch With High Resistant Starch Content(Elsevier Sci Ltd, 2015-05) 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.Article Citation - WoS: 10Citation - Scopus: 14Modelling the Effects of Debranching and Microwave Irradiation Treatments on the Properties of High Amylose Corn Starch by Using Response Surface Methodology(Springer, 2018-04-28) Mutlu, Selime; Kahraman, Kevser; Severcan, Sebnem; Ozturk, SerpilResponse 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.Article Citation - WoS: 3Citation - Scopus: 3Fabrication of Grape Pomace Extract-Loaded Electrospun Nanofiber Films as Active Packaging Material for Walnut(Springer, 2024-09-27) Yilmaz, Burcin; Kahraman, Kevser; Ekici, LutfiyeGrape pomace is a valuable residue of wine, vinegar, juice, and molasses industries with its high phenolic compound content. In this study, fabrication of gelatin/zein nanofiber films with antioxidant properties due to addition of grape pomace extract (0-20%, GPE) was assessed. This nanofiber film is designed to be evaluated as an active packaging material for coating walnuts. SEM analysis revealed that the nanofibers were uniform and bead-free, with the diameter ranging from 239 to 343 nm, and the FT-IR spectra showed that the GPE was enclosed in nanofibers successfully. The thermal stability of the extract appeared to be improved by encapsulation. The nanofibers demonstrated DPPH scavenging activity with the one containing 20% GPE exhibiting 75% inhibition. Walnuts were placed into polyethylene bags including nanofibers, and after 21-day storage, a significant (p<0.05) decrease in the peroxide values (from 1.92 meq 0(2)/kg walnut oil to 1.39 meq 0(2)/kg walnut oil) and Totox values (from 4.05 to 3.01) was shown by using GPE-loaded nanofiber. This study's results indicate that nanofibers with GPE content could be a promising package material for preserving food quality.Article Citation - WoS: 21Citation - Scopus: 23Effects of Resistant Starch Type 4 Supplementation of Bread on in Vitro Glycemic Index Value, Bile Acid-Binding Capacity, and Mineral Bioavailability(Wiley, 2019-10-28) Aribas, Merve; Kahraman, Kevser; Koksel, HamitBackground 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.Article Citation - WoS: 41Citation - Scopus: 46Effects of Germination on the Physicochemical and Nutritional Characteristics of Lentil and Its Utilization Potential in Cookie-Making(Springer, 2021-06-10) Oskaybas-Emlek, Betul; Ozbey, Ayse; Kahraman, KevserLentil is an alternative gluten-free source with high protein content. In our study, lentil seeds were germinated to enhance the functional and antioxidant properties of lentil. The raw and germinated lentil flour was obtained from lentil seed and used in cookie production. The germination affected the physicochemical, functional, chemical and morphological properties, and pasting behavior of lentil flour. The results indicated that germination caused positive effects on ash and protein content, total phenolic content (TPC), antioxidant properties, oil absorption capacity, and water solubility index. However, germination caused a decrease in the total dietary fiber and starch content due to the activation of the enzymes during germination. SEM images of the germinated lentil flour proved the degradation of starch. Lentil (raw and germinated) flour cookies and wheat flour cookies (Control) were evaluated in terms of physicochemical, TPC, antioxidant properties, textural properties, and in-vitro glycemic index (eGI) value. Germinated lentil flour cookie exhibited the lowest hardness, lightness, yellowness values, the highest TPC and antioxidant activity, and it had the same effect on eGI with control cookie. Overall results indicated that germination can be used as a natural, sustainable, and cost-effective way to improve the functional, and antioxidant properties of lentil. Germinated lentil flour cookie may be considered as a functional food due to high protein content and antioxidant properties.