Ozan Kahraman

Dr. Ozan Kahraman

Applied Food Sciences Inc.

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

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

Representative Publications

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18 February 2022 in Foods
Verified
Journal Article
Open access
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Ozan KahramanOzan Kahraman
Ozan Kahraman
GPGreg Petersen
Greg Petersen
CFChristine Fields
Christine Fields
According to the Food and Agriculture Organization (FAO), protein demand is expected to increase globally by around 40% by 2030 as a response to the world’s population growth. Due to their clean label, vegan or vegetarian based applications, nutritional value, and cost-efficient properties, plant-based proteins have been widely studied. However, most of the alternatives currently found in the market have some challenges because of their poor solubility, emulsifying, gelling, and foaming attributes. Hemp seed protein has gained increasing attention due to its unique amino acids and fatty acids profiles. In this study, commercial HPC mixtures were adjusted to pH 2, 4, 6, 8, 10, and 12 followed by ultrasonication (US) for 5 min (5 s on: 5 s off) and incubated for an hour before neutralizing to pH 7. Following the treatments, the samples were analyzed for their hydrodynamic diameter, conductivity, zeta potential, polydispersity index, surface hydrophobicity, solubility, electrophoresis (SDS-PAGE), free sulfhydryl group, and optical characteristics. The samples treated with ultrasound at pH 8 and 10 significantly (p < 0.05) enhanced the solubility of the hemp seed protein by 12.12% and 19.05%, respectively. Similarly, the samples treated with ultrasonication and pH shifting at pH 6, 8, and 10 also significantly increased the amount of free sulfhydryl content (p < 0.05) to 41.6, 58.72, and 46.54 mmol/g from 32.8 mmol/g, respectively. This study shows that the application of ultrasonication and pH shifting is a promising alternative method to modify the functional properties of HPC and widen their applications in the food, cosmetics, and pharmaceutical industries.

24 February 2024 in Foods
Verified
Journal Article
Open access
PDF file
HKHasim Kelebek
Hasim Kelebek
Hatice Kubra SASMAZHatice Kubra SASMAZ
Hatice Kubra SASMAZ
ÖAÖzge Aksay
Özge Aksay
SSSerkan Selli
Serkan Selli
Ozan KahramanOzan Kahraman
Ozan Kahraman
CFChristine Fields
Christine Fields
Guayusa tea is derived from the leaves of the Ilex guayusa Loes. plant, which is native to the Amazon rainforest. Beyond its pleasant sensory properties, Guayusa tea is rich in antioxidants, phenolics, and minerals. In this study, the effects of infusion time, temperature, and solvent conditions on the color, antioxidant capacity, total phenolic content, phenolic profile, and antimicrobial activity of Guayusa (Ilex guayusa Loes.) tea were investigated. Guayusa tea samples were prepared using two different solvents, ethanol and water, with 4, 6, and 8-h infusions at 60 and 70 °C. Liquid chromatography, diode array detection, and electrospray ionization tandem mass spectrometry (LC-DAD-ESI-MS/MS) were used to determine a comprehensive profile of phenolic compounds and to detect differences due to infusion conditions. Moreover, after the Guayusa tea infusion with the highest bioactive properties was determined, the effects of in vitro gastrointestinal digestion on the total phenolic content, antioxidant capacity, and phenolic compounds of the Guayusa tea infusion were measured. Phenolic profile analysis identified 29 compounds, among which chlorogenic acid and its derivatives were predominant. The increase in infusion time was correlated with an elevation in total phenolic content. Significant differences were observed between water and ethanol infusions of Guayusa in terms of phenolics and antioxidants. The total amount of phenolic compounds in the samples prepared with both solvents was found to increase after oral intake, depending on the digestion stage; meanwhile, the amounts of flavonoid compounds and di-O-caffeoylquinic acid derivatives decreased during digestion.
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10 September 2025 in Sustainability
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Journal Article
Open access
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Ozan KahramanOzan Kahraman
Ozan Kahraman
GPGreg Petersen
Greg Petersen
CFChristine Fields
Christine Fields
The global challenge of food waste presents an opportunity to explore the untapped potential of agricultural by-products. Coffee pulp, a major by-product of the coffee industry, is a promising source of functional polysaccharides such as coffee pectin, which can be valorized for sustainable applications in food systems. This study investigates the microencapsulation of hemp seed oil—rich in essential fatty acids and bioactive lipids—using coffee pectin and maltodextrin as wall materials via spray drying. Emulsions with varying oil-to-wall ratios were formulated and characterized for viscosity, particle size, and zeta potential. The resultant microcapsules were analyzed for physicochemical properties, encapsulation efficiency, oxidative stability (peroxide value), and in vitro release in simulated gastrointestinal fluids. Encapsulation efficiencies ranged from 63.27% to 70.77%, with lower oil content formulations exhibiting higher efficiency. The peroxide values indicated enhanced oxidative stability, with the lowest value (10.69 meq O2/kg oil) observed in the most efficient encapsulation formulation. Microcapsule morphology analysis confirmed the formation of spherical particles with varying degrees of surface roughness. Release studies demonstrated controlled oil delivery, with higher retention in gastric conditions and progressive release in intestinal fluids. These findings demonstrate the potential of upcycled coffee pulp-derived pectin as a functional, sustainable encapsulant, aligning with circular economy principles and supporting the development of stable bioactive delivery systems for nutraceutical and food applications.

6 February 2026 in Molecules
Verified
Journal Article
Open access
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YTYijin Tang
Yijin Tang
Ozan KahramanOzan Kahraman
Ozan Kahraman
AGAnthony J. Goos
Anthony J. Goos
CFChristine Fields
Christine Fields
This study describes a single-laboratory validation of an ultra-high-performance liquid chromatographic (UHPLC) method for the determination of key compounds like hericenones, hericenes, erinacines, and ergosterol in Hericium erinaceus (H. erinaceus, Lion’s Mane) raw materials and finished products. The expanding market for Hericium erinaceus (Lion’s Mane) has increased the need for practical, routine-ready analytical methods that can quantify characteristic marker compounds and strengthen quality control across both raw materials and finished products. In this study, an ultra-high-performance liquid chromatographic (UHPLC) separation method was developed for the determination of hericenones, hericenes, erinacines, and ergosterol in Hericium erinaceus raw materials and finished products. Under the optimized conditions, the major target analytes—hericenones, hericenes, erinacine A, and ergosterol—were fully resolved (Rs > 1.5) within 38 min using an HSS T3 column at 30 °C. All the peaks in the LC chromatogram of Hericium erinaceus samples and standard solutions were structurally confirmed by LC–UV-MS/MS based on the possible mass spectra. The quantitative calibration curves were linear, covering a range of 10–300 μg/mL for hericenone C, D and E, and hericene A, D and C; 3–100 μg/mL for deacylhericenone and deacylhericene; 1–50 μg/mL for erinacine A, and 5–200 μg/mL for ergosterol. Limits of quantification (LOQs) for hericenone C, D, and E and for hericene A, D, and C were approximately 9.263, 4.545, 4.650, 1.854, 10.72, and 11.18 µg/mL, respectively, while LOQs for deacylhericenone and deacylhericene were 1.083 and 2.109 µg/mL. Erinacine A and ergosterol showed LOQs of 0.642 and 8.352 µg/mL, respectively. The recovery of ergosterol was evaluated for the method at two different levels: 91.6~93.9% for 0.2% spiking and 93.0~102.6% for 0.08% spiking. The method was successfully validated, demonstrating inter-day Relative Standard Deviation (RSD) values between 1.1% and 5.7% for detected analytes across diverse matrices. This validated method provides a consistent quantification of hericenones, hericenes, erinacine A, and ergosterol across a range of commercial products and raw Hericium erinaceus materials, providing a sensitive and reliable tool for product characterization and quality control. This method provides QC laboratories with a robust, UV-based tool for standardized product characterization without requiring mass spectrometry.