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Öğe Aroma-active compounds, sensory profile, and phenolic composition of Fondillon(Elsevier Sci Ltd, 2020) Issa-Issa, Hanan; Guclu, Gamze; Noguera-Artiaga, Luis; Lopez-Lluch, David; Poveda, Rafael; Kelebek, Hasim; Selli, SerkanThe Fondillon is a wine made from overripe grapes of the Monastrell variety, which is characterized by a high alcohol content and a minimum barrel ageing of 10 years. The objective of this study was to analyze the Fondillon volatile composition, key aroma-active compounds, sensory profile and phenolic composition. Fifty-four volatile compounds were identified, quantified and classified as alcohols, esters, acids, aldehydes, lactones, phenols, hydrocarbons and ketone. From these compounds, 22 aroma-active compounds were identified, with phenylethyl alcohol, diethyl succinate and ethyl lactate having the highest flavor dilution factor. The Fondillon wines were characterized by having high intensity of alcohol, fruity and toasted odor and flavor notes, and long aftertaste. Besides, 25 phenolic compounds were also identified and quantified; the phenolic acids (gallic, protocatechuic and syringic acids) were the predominant phenolic compounds.Öğe Changes in volatile, key odorants and bioactive properties of pomegranate juice during processing into concentrate(Elsevier Sci Ltd, 2025) Salman, Eda; Guclu, Gamze; Pehlivan, Zeynep Yaren; Kelebek, Hasim; Selli, SerkanKey odorants of juices of pomegranate fruits of Hicaz variety obtained from different juice production stages (fresh: FrPJ, pasteurized: PPJ, filtered: FiPJ, and concentrated: CPJ) were examined. Processing significantly impacted the volatile compounds. The FrPJ and PPJ samples had higher concentrations of aroma compounds than the FiPJ and CPJ samples. A total of 38 aroma substances were identified in the FrPJ sample while 37, 35, and 21 compounds were detected in the PPJ, FiPJ, and CPJ samples, respectively. Phenylethyl alcohol was the dominant key odorant. The total phenolic contents (TPC) and antioxidant activities (AA) of the samples changed significantly. The CPJ sample had the highest TPC and AA due to increased release of phenolics during the concentration process; thus, this process increased the TPC and AA significantly, altering both aroma and bioactive properties. The results emphasize the importance of processing methods in preserving the nutritional and sensory qualities of pomegranate juice.Öğe Characterization of aroma and aroma-active compounds of black carrot ( Daucus carota L. ssp. sativus var. atrorubens Alef.) pomace by aroma extract dilution analysis(Cell Press, 2024) Buyukkurt, Ozlem Kilic; Guclu, Gamze; Sevindik, Onur; Kelebek, Hasim; Kelebek, Pinar Kadiroglu; Selli, SerkanThe aim of this study was to characterize the aroma and aroma-active compounds of black carrot pomace, a valuable by-product of black carrot juice industry. Aroma compounds were analyzed using GC-MS-O and extracted via the SAFE technique. The extract samples were determined to represent the odor of black carrot pomace quite well according to the results of the representative test. Accordingly, the aromatic extract scored 77.7 mm for intensity and 87 mm for similarity on a 100 mm unstructured scale. A total of 47 volatile constituents were identified and quantified including terpenes (20), alcohols (11), acids (7), esters (4), ketones (4), and lactone (1). It was observed that terpenes were the major aroma group. The use of aroma extract dilution analysis (AEDA) revealed only 29 of these compounds as aroma-active constituents. Phenylethyl alcohol (FD:512, OAV: 2488, rose) and phenylethyl acetate (FD:256, OAV:280, rose) were the aroma substances providing the strongest rose odor. Following these compounds, acetic acid (vinegar), dimethyl-propanedioic acid (pungent), (E)-beta-caryophyllene (salty cheese) and elemicin (spicy) were identified as other strong aroma-actives with FD values of 128 contributing to the characteristic odor of the black carrot pomace samples. The odor activity values (OAVs) ranged from 1 to 2488. The highest OAVs represent the high aromatic active compounds (FD >= 128). The distinctive aroma and rich color of black carrot pomace make it a recommended choice for enhancing flavor and adding natural coloring to food products.Öğe Characterization of aroma and phenolic composition of carrot (Daucus carota 'Nantes') powders obtained from intermittent microwave drying using GC-MS and LC-MS/MS(Elsevier, 2020) Keser, Duygu; Guclu, Gamze; Kelebek, Hasim; Keskin, Muharrem; Soysal, Yurtsever; Sekerli, Yunus Emre; Arslan, AyselCarrot is an important food in human nutrition. The effects of different microwave (MW) powers on the aroma, phenolic and antioxidant properties of MW-dried and powdered carrot samples were investigated. Fresh carrot samples (Daucus ca rota 'Nantes') were dried using seven different MW power levels of 150, 200, 250, 300, 350, 400 and 450 W (0.50, 0.67, 0.83, 1.00, 1.17, 1.33 and 1.50 W/g, respectively). The aroma compounds of the carrot samples were extracted by purge and trap method and determined by gas chromatography-mass spectrometry (GC MS). In fresh samples, terpenes were identified as the dominant aroma group and a significant reduction was found in the amount of these compounds depending on the applied MW power level. Terpinolene, (E)-gamma-bisabolene, elemicin and myristicin were identified as dominant terpenes. In the dried samples, aldehydes, furans, alcohols, acids and pyrazines were determined as major components depending on the applied MW power levels. Hexanal, 3-methyl-butanal, acetic acid and hexanoic acid were dominant in the dried samples. For the determination of the phenolic compounds, the method of liquid chromatography coupled with tandem mass spectrometry (LC MS/MS) was employed. As a result of the analysis, a total of seven phenolic compounds, two of which were more dominant (3-caffeoylquinic acid and di-caffeic acid derivative) were identified. The total phenolic content of the carrot samples dried with lower MW power level of 150 and 200 W (0.50 and 0.67 W/g) was found to be relatively better preserved. When both aroma and phenolic compounds were evaluated, it was observed that they were better preserved in the carrot samples dried with low MW power levels (150 and 200W). (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.Öğe Comparative assessment of volatile and phenolic profiles of fresh black carrot (Daucus carota L.) and powders prepared by three drying methods(Elsevier, 2021) Keskin, Muharrem; Guclu, Gamze; Sekerli, Yunus Emre; Soysal, Yurtsever; Selli, Serkan; Kelebek, HasimDrying is a common method in the post-harvest processing of fruits and vegetables and it can play a crucial role on the quality of the final product. This work examined the influence of three drying processes (freeze-drying: FD, intermittent microwave drying: IMWD and hot air convective drying: HACD) on the aroma and phenolic constituents of black carrot which is an essential vegetable in terms of its nutritive and health benefits. It was found that the drying process had substantial effects on the aroma and phenolic compositions of the black carrot powder samples. GC-MS analysis revealed a total of 32 volatiles in all samples. The FD samples had more numbers of aroma compounds after the fresh samples. Prevailing aroma groups were terpenes and alcohols. The highest amount of volatiles was found in the FD samples meaning that the FD played a crucial role in conserving the volatiles as compared to the HACD and IMWD. HPLC-DAD-ESI-MS/MS analysis yielded 34 constituents including 22 colorless phenolics and 12 anthocyanins. Regarding the phenolics, the highest amount was quantified in the HACD and IMWD samples. Chlorogenic acids were the major phenolic acids. The FD and IMWD caused a decline in the amount of anthocyanins while HACD resulted in an increase. Sensory analysis revealed that the FD method conserved the aroma to a greater extent and its overall acceptability was higher.Öğe Comparative elucidation of phenolic compounds in Albanian olive oils using LC-DAD-ESI-MS/MS(Taylor & Francis Inc, 2020) Topi, Dritan; Guclu, Gamze; Kelebek, Hasim; Selli, SerkanOlive oils may provide health benefits, including the prevention of coronary heart diseases, cancers, and the modification of immune and inflammatory responses. These benefits mainly originate from the phenolic compounds found in olive oil. There has been no study on the advanced characterization of Albanian olive oils from various cultivars regarding phenolic compounds. Hence, a comprehensive characterization of phenolic compounds is carried out in Albanian monocultivar virgin olive oils from five different cultivars, including Kalinjot, Bardhi Tirana, Ulliri-i-Zi Tirana, Krips Kruja, and Bardhi Kruja for the first time. Liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI-MS/MS) is employed for the determination of phenolic compounds. In total, 18 compounds were identified in all samples, including phenolic alcohols, phenolic acids, secoiridoids, flavonoids, and phenolic aldehydes. Significant quantitative differences were detected among the cultivars, with the highest concentrations detected in virgin olive oil (VOO) from cv. Ulli-i-Zi. Secoiridoids were found in abundance, in general, followed by phenolic alcohols, and in this group, 3,4-DHPEA-EDA and p-HPEA-EDA stood out as dominant compounds, especially in Kalinjot virgin olive oils. Regarding phenolic alcohols, 3,4-DHPEA-AC was determined as the main phenolic compound. Phenolic profiles were found to be significantly different among the olive oil samples of different cultivars. Principal component analyses (PCA) displayed the differentiation of samples in terms of phenolic compounds.Öğe Comparative elucidation of the phenolic profile and antioxidant and antimicrobial activities of unripe and ripe Pistacia lentiscus L. fruits and their oils as affected by ripening(Wiley, 2025) Buyukkurt, Ozlem Kilic; Guclu, Gamze; Kelebek, Hasim; Selli, SerkanBackgroundPhenolic compounds, antioxidant activity, and antimicrobial properties of unripe and ripe mastic tree (Pistacia lentiscus L.) fruits and their oils were investigated.ResultsA total of 20 phenolic compounds were identified by using liquid chromatography-diode array detection and electrospray ionization tandem mass spectrometry, among which phenolic acids were predominant. The main phenolic compound was catechin in the unripe fruit and trigalloylquinic acid in the unripe fruit oil, whereas galloylquinic acid was dominant in the ripe fruit and its oil. Unripe fruits had the highest amount of total phenolic content (TPC; 2771.4 mg kg-1), whereas the ripe fruit oils had the lowest TPC (14.1 mg kg-1). The quantity of the phenolics decreased as the fruits ripened. Tests revealed significant antimicrobial activity of the fruit extracts against Staphylococcus aureus but not on Escherichia coli, whereas fruit oils showed no antimicrobial effects.ConclusionThe fruits and their oils exhibited significant alterations in phenolic composition, antioxidant activity, and antimicrobial effects during ripening. These findings highlight the impact of ripeness on the bioactive properties of mastic tree fruits and their potential applications in the food and pharmaceutical industries. (c) 2025 Society of Chemical Industry.Öğe Comparative Study of the Aroma Profiles and Bioactive Properties of Cooked and Uncooked Regular and Firik Bulgurs(Wiley, 2025) Kilic-Buyukkurt, Ozlem; Guclu, Gamze; Keskin, Muharrem; Kelebek, Hasim; Selli, SerkanBackground and Objectives Bulgur is an important cereal product preferred due to its aroma, nutrition, and economic values. In this study, the effect of cooking process applied to two different bulgur types (regular and firik) on the aroma profile, color properties, total phenolic content (TPC), and antioxidant activity (AA) was evaluated. Findings A total of 27 and 33 aroma compounds were detected in the uncooked and cooked regular bulgur samples, while the firik bulgur samples (uncooked and cooked) had 27 and 34 compounds, respectively. Cooking process caused significant changes, with carboxylic acids and aldehydes being the dominant aroma groups. Uncooked firik bulgur exhibited the highest aroma concentration. Generally, both cooked (4225.6 ng/kg) and uncooked (4745.2 ng/kg) firik bulgurs had higher total aroma concentrations compared to the regular bulgurs (2333.0 and 3255.1 ng/kg). It was found that significant differences (p < 0.05) were observed in the TPC and AA levels; they were higher in firik bulgurs but decreased with the effect of cooking. Conclusion The study highlights that bulgur type and cooking process significantly affect its aroma and phenolic properties, potentially influencing consumer preferences. This is the first study to examine the aroma and bioactive compound variations in two bulgur types with respect to cooking.Öğe Decoding the Changes of Volatiles and Key Odorants of Fresh Garlic and Black Garlic Produced with Different Parameters by GC-MS-Olfactometry(Amer Chemical Soc, 2024) Sasmaz, Hatice Kubra; Guclu, Gamze; Sevindik, Onur; Selli, Serkan; Kelebek, HasimThe effects of production parameters on aroma compounds were elucidated by conducting a detailed comparison between fresh and black garlic samples, providing new insights that contribute to the existing body of literature on aroma compound analysis in garlic. A total of 113 aroma compounds were identified including sulfur compounds, aldehydes, ketones, pyrazines, furans, thiophenes, volatile alcohols, and acids. The aroma profile of the black garlic samples varied depending on factors such as temperature, humidity, and fermentation duration. The black garlic sample with the highest aroma quantity was the one produced at the lowest temperature, humidity, and duration. Additionally, a total of 34 aroma-active compounds that create the characteristic odor of fresh and black garlic samples were determined by GC-MS-O and aroma extract dilution analysis (AEDA). The fresh garlic sample contained allyl methyl disulfide and diallyl disulfide, which are responsible for the characteristic garlic odor, while in the black garlic samples, furfuryl alcohol was found to be the most dominant aroma-active compound. The findings of this study will help better elucidate the impacts of production process parameters on the aroma and aroma-active profiles of black garlic.Öğe Determination of Volatiles by Odor Activity Value and Phenolics of cv. Ayvalik Early-Harvest Olive Oil(Mdpi, 2016) Guclu, Gamze; Sevindik, Onur; Kelebek, Hasim; Selli, SerkanAyvalik is an important olive cultivar producing high quality oils in Turkey. In the present study, volatile and phenolic compositions of early-harvest extra virgin olive oil (cv. Ayvalik) were determined. The solvent-assisted flavor evaporation (SAFE) technique was used for the extraction of volatile components. The aromatic extract obtained by SAFE was representative of the olive oil odor. A total of 32 aroma compounds, including alcohols, aldehydes, terpenes, esters, and an acid, were identified in the olive oil. Aldehydes and alcohols were qualitatively and quantitatively the most dominant volatiles in the oil sample. Of these, six volatile components presented odor activity values (OAVs) greater than one, with (Z)-3-hexenal (green), hexanal (green-sweet) and nonanal (fatty-pungent) being those with the highest OAVs in olive oil. A total of 14 phenolic compounds were identified and quantified by liquid chromatography combined with a diode array detector and ion spray mass spectrometry. The major phenolic compounds were found as 3,4-DHPEA-EDA, 3,4-DHPEA-EA and p-HPEA-EDA.Öğe Elucidating the contribution of microorganisms to the spontaneous fermentation and the quality of Ivorian cacao (Theobroma cacao) beans: The quality of Ivorian cacao (Theobroma cacao) beans(Codon Publications, 2022) Oussou, Kouame Fulbert; Guclu, Gamze; Kelebek, Hasim; Selli, SerkanCacao (Theobroma cacao) beans are among the most important ingredients in food and beverage industries. They are mainly produced in tropical and subtropical forests. Africa is the biggest producer of cacao bean providers in the world and the Ivory Coast remains the world leader with an estimated yearly production of 3 million tonnes. Cacao beans are used in many food items such as chocolate products, cocoa butter, confectionary products, iced drinks, cocoa powder, etc. The quality and organoleptic characteristics of these food products are strongly related to those of the cocoa beans obtained from different processing treatments. The pulps surrounding the cacao beans are rich in water, sugars, pectins, proteins, minerals, vitamins, citric acid, and phenolic compounds. Many different processing methods are utilized and fermentation is a crucial postharvest treatment having a great influence on the quality of cacao beans and their related products. Spontaneous fermentation is a common prac-tice carried out by the cacao farmers in Ivory Coast. The microorganisms involved in this process are primarily the yeasts (anaerobic phase), which convert the pulps containing sugars into alcohol with a sporicidal temperature increase and then the lactic and acetic acid bacteria (aerobic phase) that produce lactic and acetic acids, respec-tively. The degradation of the substrates inside the cacao pulps results in the generation of aroma precursors and compounds. The goal of this review was to elucidate the factors affecting the spontaneous fermentation of Ivorian cacao beans and clarify the transformation of the raw material during fermentation.Öğe Elucidation of key aroma enhancement in cloudy lemon juices by the addition of peel oil using GC-MS-Olfactometry(Wiley, 2022) Yetisen, Mehmet; Guclu, Gamze; Kelebek, Hasim; Selli, SerkanVolatile substances play a crucial role in the consumer preference of lemon juices. The effects of heat treatment and addition of lemon peel oil to lemon juice (Citrus limon Burm. cv. Kutdiken) on the aroma compounds were elucidated for the first time. Total phenolic, antioxidant activity, acidity, pH and colour properties were also studied. Results revealed that the aroma of the juice samples comprised mostly the terpene compounds. Limonene, gamma-terpinene, beta-pinene and alpha-pinene were the influential terpenes responsible for the distinctive odour of the lemon juice. The addition of the lemon peel oil increased the amounts of the aroma and aroma-active compounds. Besides, the heat treatment had a positive effect on the total phenolics and the antioxidant activity but it caused significant reduction of the aroma compounds. Sensory analysis revealed that the most preferred sample was the juice with lemon peel oil added after pasteurisation.Öğe Elucidation of the impact of four different drying methods on the phenolics, volatiles, and color properties of the peels of four types of citrus fruits(Wiley, 2022) Guclu, Gamze; Polat, Suleyman; Kelebek, Hasim; Capanoglu, Esra; Selli, SerkanBACKGROUND Citrus fruit peels are considered to be process waste in the fruit juice industry but they are a valuable raw material due to their volatile and bioactive components. Drying is one of the most common methods to preserve this material. In this study, four drying processes were applied to the peels of four kinds of citrus fruits. The drying processes were convective drying (CD), microwave drying (MD), conductive hydro drying (CHD), and freeze drying (FD). The citrus fruits used were orange, bitter orange, grapefruit, and lemon. RESULTS The influence of dehydration on the aroma and phenolic composition, microstructure, and color properties were studied in detail. It was determined that drying increased the amount of both phenolics and volatiles in the dried samples. The MD and FD methods better preserved the color and phenolics of the samples, and the MD and CD processes increased the amount of aroma substances. CONCLUSION The MD method would be more suitable for drying citrus peels due to its shorter duration and its positive effects on the phenolic and aroma components. (c) 2022 Society of Chemical Industry.Öğe Impact of production and drying methods on the volatile and phenolic characteristics of fresh and powdered sweet red peppers(Elsevier Sci Ltd, 2021) Guclu, Gamze; Keser, Duygu; Kelebek, Hasim; Keskin, Muharrem; Sekerli, Yunus Emre; Soysal, Yurtsever; Selli, SerkanAroma, phenolic compounds and sensory properties of fresh and powdered organic and conventional sweet red peppers dried by three methods (hot air, intermittent microwave and infrared) were studied. The number of aroma compounds was higher in both fresh and powdered organic pepper samples; however, the total amount was higher in conventional samples. In both organic and conventional samples, alcohols were the dominant aroma group. (E)-beta-ionone and beta-ocimene, which are important compounds in peppers, were determined only in organic peppers. Among the drying methods, intermittent microwave drying was more effective in creating new aroma compounds. The liquid chromatography, coupled with tandem mass spectrometry (LC-MS/MS) revealed that luteolin derivative compounds comprised an average of 70% of the phenolics. Higher amount of phenolic were determined in organic samples. Infrared drying was more effective in retaining of phenolics than the other two methods. Sensory analysis revealed that hot air-dried samples were least preferred.
