WoS İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394

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  • Article
    Development of Resistant Starch Type-5 and Its Utilization in Cookie-Preparation
    (North University Center Baia Mare, 2025-11-30) Oskaybas-Emlek, Betul; Ozbey, Ayse; Kahraman, Kevser
    The objective of this study was the production of resistant starch type-5 (RS-5), its characterization, and utilization in cookie making. In first part of the study, the effects of starch-fatty acid complex formation (RS-5) between tapioca starch and lauric acid on the structure, digestibility, thermal and morphological properties of tapioca starch were investigated. X-ray diffraction revealed that the RS-5 had a V-type crystalline pattern. FT-IR analysis showed that a distinctive peak at 2846 cm-1 was only observed in RS-5. The resistant starch (RS) content of native starch increased from 22.76% to 28.02% with RS-5 formation. In the second part of the study, the RS-5 was added as a replacement for wheat flour with 10%, 20%, and 30% compared to control sample made with 100% wheat flour in cookie-making. The effects of RS-5 replacement of cookie samples on some physicochemical, estimated glycemic index (eGI) value, physical, and hardness properties were determined. Compared to control cookie, the cookie samples included RS-5 had lower hardness value, higher spread ratio. The eGI value of cookie samples was slightly decreased with the replacement with RS-5. The results demonstrated that the RS-5 has good potential for developing softer cookie with no adverse impact on eGI value.
  • 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, 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.
  • 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, 2021-08-25) 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.
  • Article
    Citation - WoS: 40
    Citation - Scopus: 63
    Optimization of Resistant Starch Formation From High Amylose Corn Starch by Microwave Irradiation Treatments and Characterization of Starch Preparations
    (Elsevier, 2017-02) Mutlu, Selime; Kahraman, Keyser; Ozturk, Serpil
    The effects of microwave irradiation on resistant starch (RS) formation and functional properties in high-amylose corn starch, Hylon VII, by applying microwave-storing cycles and drying processes were investigated. The Response Surface Methodology (RSM) was used to optimize the reaction conditions, microwave time (2-4min) and power (20-400%), for RS formation. The starch:water (1:10) mixtures were cooked and autoclaved and then different microwave-storing cycles and drying (oven or freeze drying) processes were applied. The RS contents of the samples increased with increasing microwave storing cycle. The highest RS (43.4%) was obtained by oven drying after 3 cycles of microwave treatment at 20% power for 2 min. The F, p (<0.05) and R-2 values indicated that the selected models were consistent. Linear equations were obtained for oven-dried samples applied by 1 and 3 cycles of microwave with regression coefficients of 0.65 and 0.62, respectively. Quadratic equation was obtained for freeze-dried samples applied by 3 cycles of microwave with a regression coefficient of 0.83. The solubility, water binding capacity (WBC) and RVA viscosity values of the microwave applied samples were higher than those of native Hylon VII. The WBC and viscosity values of the freeze-dried samples were higher than those of the oven-dried ones. (C) 2016 Elsevier B.V. All rights reserved.
  • 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, 2015-05) 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: 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, 2018-04-28) 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.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    Formation of Resistant Starch From Amylotype Corn Starch and Determination of the Functional Properties
    (Wageningen Academic Publishers, 2013-12) Kahraman, K.; Koksel, H.
    High amylose corn starch was hydrolysed with HCl at 40 degrees C for 0.5-2.0 h. Then the native and acid-modified starch samples were subjected to 2 different heat treatments (HT). In HT1, heat treated/autoclaved samples were dried after storage and in HT2, heat treated/autoclaved samples were dried without storage. Relative quantities of high- and medium-molecular weight fractions decreased and relative quantities of low-molecular weight fractions increased as a result of acid modification. Resistant starch (RS) contents of the acid-modified starches were between 15.7-16.4% and increased up to 29.4% due to HT1 and up to 17.5% due to HT2. The results indicated that RS contents of the high amylose starch can be increased by HT and storing prior to drying. Rapid ViscoAnalayser viscosity values decreased as the acid modification level increased. Water absorption and solubility values of the samples prepared with both heat treatments were higher than those of the native starch and hydrolysates. Emulsifying capacity/stability values of soy protein solution supplemented with the hydrolysates and heat treated samples were higher than those supplemented with the native and heat treated native starch.
  • Article
    Citation - WoS: 51
    Citation - Scopus: 57
    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, 2019-11) 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.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 9
    A Novel High-Amylose Wheat-Based Functional Cereal Soup (Tarhana) With Low Glycemic Index and High Resistant Starch
    (Academic Press Ltd- Elsevier Science Ltd, 2024-05) Koksel, Hamit; Tekin-Cakmak, Zeynep Hazal; Ozkan, Kubra; Pekacar, Zeynep; Oruc, Sena; Kahraman, Kevser; Sestili, Francesco
    This study investigated the potential of high-amylose wheat flour (Svevo-HA) to enhance the dietary profile of tarhana, a traditional Mediterranean fermented cereal yogurt mixture. The moisture content of tarhana powders ranged from 7.81% to 11.64%. Color parameters varied depending on the type of flour used, with Svevo-HA samples demonstrating decreased L* values and increased a* and b* values. Mineral compositions differed significantly among tarhana samples, with higher levels of K, Mg, Mn, Fe, Cu, and Zn observed in samples prepared with Svevo-HA. Gallic acid was identified as the major phenolic compound in all the tarhana samples for free fraction, while ferulic acid was determined as the major phenolic compound for its bound form. Supplementation of tarhana soups with heat-treated Svevo-HA flour increased the resistant starch content and decreased in vitro glycemic index value compared to soups prepared with conventional wheat flour. These findings highlight the potential of utilizing Svevo-HA flour to develop healthier versions of traditional foods.