Gulsah OZCAN SINIR

Dr. Gulsah OZCAN SINIR


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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19 July 2022 in Foods
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Journal Article
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AKAzime Özkan Karabacak
Azime Özkan Karabacak
GSGulsah OZCAN SINIR
Gulsah OZCAN SINIR
AÇAli Eren Çopur
Ali Eren Çopur
MBMurat Bayizit
Murat Bayizit
The effect of osmotic dehydration (OD) pretreatments at different temperatures and immersion times on drying characteristics, total phenolic content (TPC), total antioxidant activity (TAA) (DPPH and CUPRAC methods), and color of kumquat slices dried under vacuum conditions (70 °C-100 mbar) was investigated. The OD pretreatment was performed in a sucrose solution (45 °Bx) at the temperatures of 40 and 50 °C and immersed at times of 30, 60, and 90 min. OD before vacuum drying decreased the total required drying time by up to 70 min compared to the control non-pretreated samples. Page, Modified Page, Henderson Pabis, and Two Terms Exponential models were found to satisfactorily describe the drying behavior of thin layer dried kumquat slices. The minimum and maximum values of effective moisture diffusivity (Deff) for semi-dried kumquat slices were 5.04 × 10−8 to 7.19 × 10−8, respectively. OD treatments induced a decline in TPC (5.30–33.92%) and TAA (23.63–59.34% and 4.17–31.67% for DPPH and CUPRAC assays, respectively) of kumquat slices. It was observed that OD pre-treatment can decrease the gross drying time, and make the color and sensorial attributes of dried kumquats better.

4 January 2020 in Journal of the Science of Food and Agriculture
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GSGulsah OZCAN SINIR
Gulsah OZCAN SINIR
ÖÇÖmer Utku ÇOPUR
Ömer Utku ÇOPUR
SBSHERYL BARRINGER
SHERYL BARRINGER
BACKGROUND: Honey has a very important commercial value for producers as a natural product. Honey aroma is formed from the contributions of several volatile compounds, which are influenced by nectar composition, botanical origins, and location. Selected‐ion flow‐tube mass spectrometry (SIFT‐MS) is a technique that quantifies volatile organic compounds simply and rapidly, even in low concentrations. In this study, the headspace concentration of eight monofloral (chestnut, rhododendron, lavender, sage, carob, heather, citrus, and pine) and three multiflower Turkish honeys were analyzed using SIFT‐MS. Soft independent modeling of class analogy (SIMCA) was used to differentiate honey samples based on their volatiles.RESULTS: This study focused on 78 volatile compounds, which were selected from previous studies of selected honeys. Very clear distinctions were observed between all honeys. Interclass distances greater than 8 indicate that honeys were significantly different. Methanol and ethanol were abundant in the honeys. Chestnut honey collected from the Yalova region had the highest total concentration of volatiles followed by heather honey and chestnut honey collected from the Düzce region.CONCLUSION: Honeys with different botanical and geographical origins showed differences in their volatile profile based on chemometric analysis. Of the honey samples, methanol, ethanol, acetoin, ethyl acetate, and isobutanoic acid had the highest discriminating power. Methanol and ethanol, and then acetic acid, were the volatiles with the highest concentrations in most honeys. © 2020 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

16 July 2018 in Beverages
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SSSenem SUNA
Senem SUNA
GSGulsah OZCAN SINIR
Gulsah OZCAN SINIR
CTCanan Ece Tamer
Canan Ece Tamer
BIBige İncedayi
Bige İncedayi
ÖÇÖmer Utku ÇOPUR
Ömer Utku ÇOPUR
The current study was aimed to generate an innovative tea beverage which has water infusion of Erica arborea. Dehydrated Erica arborea leaves were extracted in boiling water and the solution was brix value-balanced to 8° with sucrose, acid, natural lemon flavor, and antimicrobial agents. Following the blending of additives, carbonation was applied. Besides some physicochemical parameters, total phenolics, bioaccessibility of total phenols, antioxidant capacity, and bioaccessible antioxidants with 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and cupric ion reducing antioxidant capacity assay (CUPRAC) methods were also investigated. The green- and yellow-tinted beverage was especially rich in potassium and calcium. The total phenolics and bioaccessible phenolics of the beverage were identified as 174.06 ± 24.53 mg Gallic Acid Equivalent (GAE) 100 mL−1 and 96.07 ± 3.96 mg GAE 100 mL−1, correspondingly. Antioxidant capacity was 27.20 ± 1.09 μmol trolox mL−1, and the bioaccessible antioxidant capacity was 0.17 ± 0.02 μmol trolox mL−1 in DPPH. Measured antioxidant capacity and bioaccessible antioxidant capacity with other assays were 22.41 ± 2.49 and 3.09 ± 0.44 μmol trolox mL−1 for FRAP; 21.09 ± 1.65 and 0.02 ± 0.00 μmol trolox mL−1 for CUPRAC. In addition to its nutritional and functional features, Erica arborea tea beverage is preferred in accordance with the panelists’ sensorial decision.