Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Influence of Innovative Thawing Approaches on the Thermal and Chemical Structure Changes of Frozen Beef Liver(Springer, 2026) Avsar, Nazlican; Uzuner, SibelFreezing effectively preserves meat quality, but the formation of ice crystals during the process can impact tenderness and functionality. Thawing is a critical step, as it can lead to physicochemical changes-such as protein oxidation and further ice crystal growth-that may reduce product quality and consumer appeal. Therefore, the thawing method plays a key role in determining the final quality of frozen meat. This study evaluated the physicochemical and structural characteristics of beef liver frozen at - 18 +/- 2 degrees C for 20 h and thawed using three methods: water immersion thawing (WIT), ultrasonic bath thawing (UBT), and air fryer thawing (AFT). No significant differences in drip loss were observed among the UBT, AFT, and WIT samples (p > 0.05). Color measurements (L*, a*, b*) were significantly higher in raw liver than in AFT and UBT samples (p < 0.05). Compared to raw liver and the WIT method, AF and UB thawing lowered the denaturation temperature, indicating reduced thermal stability. The lowest metmyoglobin (MetMb) content was found in the UBT sample (36.57 +/- 0.87%), followed by the AFT sample (41.71 +/- 1.29%), suggesting better pigment preservation with UB thawing. Highlights circle AF and UB thawing methods resulted in a lower denaturation temperature. circle UBT showed the lowest MetMb content, helping to minimize oxidation. circle UBT caused less damage to protein chains and better preserved structural stability. circle UBT preserved desirable aroma characteristics more effectively.Article 3D-Printed Soy Protein and Microalga Films: A Sustainable Approach with Antioxidant Functionality(Elsevier, 2026) Barekat, Sorour; Dogan, Buse; Uzuner, Sibel; Ubeyitogullari, AliThis study investigated the optimization and fabrication of soy protein isolate (SPI)-green microalga (MA) 3D-printed films. For optimizing 3D printing, the effects of MA concentration, nozzle size (0.52-0.81 mm), and speed (10-20 mm/s) were examined. The printed films were then dried, and color, mechanical properties, water vapor permeability, structure, and antioxidant activity were analyzed. All the formulations showed shear-thinning behavior and rapid recovery. The concentration of 3 % MA, nozzle size of 0.72 mm, and printing speed of 20 mm/s were selected as the optimized conditions for the best 3D printability. Compared with the control, their elongation at break decreased by more than 16 %, while puncture strength increased by over 12 %, and tensile strength rose by more than 40 %. Water vapor permeability decreased by more than 40 % with the addition of MA. The microstructure images and secondary structure confirmed the formation of a less porous and stronger gel network with an increase in MA concentration from 0 to 5 % (w/w). The antioxidant properties of SPI films also increased two-fold with the addition of MA. These findings highlight that the 3D-printed edible films with antioxidant properties could be used as an eco-friendly and nutritious alternative to petroleum-based films in food packaging.Article Valorizing Sugar Industry Byproduct Through Microalga for Pigment Production(Springer, 2025) Engin, Iskin; Uzuner, SibelCurrently, consumers are seeking ways to obtain natural food colorants, and food supplements. Microalgal food colorants and supplements have become established in the food industry due to their ability to generate substantial biomass rich in polysaccharides, pigments, lipids, vitamins, and other bioactive compounds. However, the high costs associated with microalgal cultivation have gained interest in more economical alternatives. This study investigated the potential of using vinasse, a byproduct of the sugar industry, as a nutrient source to produce biomass, chlorophyll, and carotenoids with Parachlorella kessleri SAG211-11 h. The effects of culture conditions (vinasse concentration, light intensity and light/dark cycle) on chlorophyll a (Chl a), chlorophyll b (Chl b), and carotenoid content were investigated using Response Surface Methodology. The results showed that light intensity and light/dark cycle had a significant effect, especially on Chl a content (p < 0.05). Light intensity also showed a significant effect on Chl b and carotenoid content (p < 0.05). Response optimization was conducted under conditions of 5% vinasse concentration, 110 mu mol photons m(-2)s(-1), and 16:8 light dark cycle, yielding a Chl a content of 10.89 +/- 0.14 mg/L, Chl b content of 7.25 +/- 1.12 and carotenoid content of 2.79 +/- 0.94 mg/L. These results revealed that the chlorophyll content of P. kessleri cells can be enhanced under mixotrophic conditions by changing cultivation conditions with the usage of vinasse-based medium. Meanwhile, this research highlights vinasse as a sustainable carbon source for the cultivation of P. kessleri SAG211-11 h cells for chlorophyll and carotenoid production.Article Citation - WoS: 1Citation - Scopus: 1Enhancing the Sustainable Protein Extraction Process From Black Cumin Seed Cake Press for Eco-Friendly Protein Supplements(Springer Science and Business Media Deutschland GmbH, 2025) Ammas, B.; Uzuner, Sibel; Uzuner, S.Finding new protein sources is essential to meet the global population’s needs. Nigella sativa (black cumin) seeds and the residual cake left after oil cold pressing contain valuable nutritional compounds, including proteins, phenolics, essential amino acids, and various bioactive compounds. In the literature, the structural characteristics and functional properties of proteins from black cumin seeds have been extensively studied. However, there are limited reports on the use of emerging extraction technologies for extracting soluble proteins from black cumin seed cake press (BCSCP). Therefore, two distinct extraction techniques—microwave (MW) and ultrasonication (US)—were assessed for their effectiveness in extracting soluble proteins from BCSCP. The aim of this study was to investigate the effects of various operational conditions on protein extraction yield and functional properties of proteins extracted from BCSCP. The maximum protein yield (27.04%) was achieved using a 10% solid/liquid ratio (SLR) at 33 °C for a 30-min extraction time with the US extraction technique. After ultrafiltration, the protein yield increased to 33.83%, showcasing the predominance of sarcosine (17.18 g/100 g), glutamine (11.63 g/100 g), and proline (33.46 g/100 g) amino acids. The water-holding capacity (WHC), oil-holding capacity (OHC), foam capacity (FC), and foam stability (FS) of the BCSCP isolate were found to be 5.4 ± 0.3 g/g, 9.4 ± 0.0 g/g, 43.6 ± 6.4%, and 39.0 ± 4.7%, respectively. The study revealed that US is a suitable extraction process for obtaining soluble proteins from BCSCP with favorable functional properties. Further studies are needed to evaluate the bioavailability and health impacts of bioactive peptides in order to develop food applications. © The Author(s) 2024.Book Part Citation - Scopus: 1Enzyme Technology in Value Addition of Wine and Beer Processing(Elsevier, 2022) Uzuner, SibelSome endogeneous and exogeneous enzymes participate in the brewery and winery technologies. Industrial enzymes provide quantitative advantages (increased juice yields) and qualitative advantages (enhanced extraction and flavor) for processing (shorter maceration, settling, and filtration time). This review aims to explain the flow process of brewing and wine-making, discuss different enzymes used in brewery and wine-making industry. Also, this chapter summarizes the key enzymes used at different stages of wine-making and brewing, and the challenges of the exogeneous, commercial and immobilized enzymes. Finally, the use of immobilized enzymes is presented as a significant strategy to improve catalyst during brewing and wine-making.