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    A Comprehensive Analysis of Apricot Drying Methods via Multi-Criteria Decision Making Techniques
    (Wiley, 2024) Abdulvahitoglu, Asli; Abdulvahitoglu, Adnan; Cengiz, Nurten
    Food and food safety have been among the most important issues for people throughout history. Societies have always tried to be self-sufficient in food and have avoided becoming dependent on foreign sources. However, the fact that most foods are seasonal and the increasing population's food consumption have revealed the need to preserve foodstuffs for a long time. The old and well-known method used today for extending shelf life is the drying process. The drying process is preferred over other preservation methods for reasons such as being more economical, easier to transport, having a longer shelf life, more concentrated nutritional value, and containing fewer additives. This ensures that dried foods are of higher quality in terms of physical, chemical, microbial properties, and nutritional values compared to other packaged foods. While the drying process was traditionally done over a long period, technological advancements have led to the production of higher quality and more valuable commercial products in a shorter time. In this study, traditional and technological methods used in drying apricots were compared according to the parameters determined by experts in the field. Since multiple parameters are effective in the comparison, Multi-Criteria Decision Making (MCDM) techniques were used. The optimum apricot drying method was determined by combining the results obtained from different MCDM techniques with the Borda rule.
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    Öğe
    A Comprehensive Analysis of Apricot Drying Methods via Multi-Criteria Decision Making Techniques
    (Wiley, 2024) Abdulvahitoglu, Asli; Abdulvahitoglu, Adnan; Cengiz, Nurten
    Food and food safety have been among the most important issues for people throughout history. Societies have always tried to be self-sufficient in food and have avoided becoming dependent on foreign sources. However, the fact that most foods are seasonal and the increasing population's food consumption have revealed the need to preserve foodstuffs for a long time. The old and well-known method used today for extending shelf life is the drying process. The drying process is preferred over other preservation methods for reasons such as being more economical, easier to transport, having a longer shelf life, more concentrated nutritional value, and containing fewer additives. This ensures that dried foods are of higher quality in terms of physical, chemical, microbial properties, and nutritional values compared to other packaged foods. While the drying process was traditionally done over a long period, technological advancements have led to the production of higher quality and more valuable commercial products in a shorter time. In this study, traditional and technological methods used in drying apricots were compared according to the parameters determined by experts in the field. Since multiple parameters are effective in the comparison, Multi-Criteria Decision Making (MCDM) techniques were used. The optimum apricot drying method was determined by combining the results obtained from different MCDM techniques with the Borda rule.
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    Öğe
    Antioxidant Capacity and Bioactive Ingredients of Asian Pear
    (2024) Cengiz, Nurten; Ercan, Leyla
    The combinations of soluble sugars, organic acids, and volatile organic compounds (VOCs) are crucial for how food is perceived and accepted. In order to evaluate the volatile organic compounds (VOCs) in Asian pears (Pyrus pyrifolia), headspace solid-phase microextraction (HS-SPME) was combined with gas chromatography-mass spectrometry (GC-MS) in this study. Among the 19 aroma compounds identified in the study conducted with a PDMS fiber, acetaldehyde and ethanol were found to be the most abundant. In addition, two more significant organic acids found in Asian pears were found to be malic acid (46.89 mg/100 g) and tartaric acid (45.08 mg/100 g). Glucose (84.70 mg/100 g) and sorbitol (65.75 mg/100 g) were identified in significant concentrations among the soluble sugars that directly affect fruit quality. LC-MS was used to investigate the phenolic content of Asian pears, and important phenolic compounds such as quinic acid (19227 g/L), chlorogenic acid (8445 g/L), procyanidin B2 (3146 g/L), liquiritin (435.1 g/L), and benzoic acid (363.1 g/L) were found.
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    Application of Molecularly Imprinted Polymers for the Detection of Volatile and Off-Odor Compounds in Food Matrices
    (Amer Chemical Soc, 2022) Cengiz, Nurten; Güçlü, Gamze; Kelebek, Haşim; Capanoglu, Esra; Selli, Serkan
    Molecularly imprinted polymers (MIPs) are synthetic receptors having specific cavities intended for a template molecule with a retention mechanism that depends on molecular recognition of the targeted constituent. They were initially established for the detection of minor molecules including drugs, pesticides, or pollutants. One of the most remarkable areas where MIPs have potential utilization is in food analysis, especially in terms of volatile compounds which are found in very low concentrations in foods but play a crucial role for consumer preference and acceptance. In recent years, these polymers have been used extensively for sensing volatile organic and off-odor compounds in terms of food quality for selective high-extraction purposes. This review first summarizes the basic principles and production processes of MIPs. Second, their recent applications in the separation, identification, and quantification of volatile and off-odor compounds in food samples are elucidated.
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    Characterization of volatile compounds in the water samples from rainbow trout aquaculture ponds eliciting off-odors: understanding locational and seasonal effects
    (Springer, 2024) Cengiz, Nurten; Güçlü, Gamze; Kelebek, Haşim; Mazi, Hidayet; Selli, Serkan
    The quality of water used in aquaculture ponds is one of the crucial factors influencing the smell and sensory properties of fish. The water samples were taken from the rainbow trout fish ponds from three different fish farms in three provinces in Türkiye in four different seasons. The samples were analyzed for the volatile components by employing HS-SPME/GC–MS. Seven different volatile groups including aldehydes, ketones, esters, alcohols, volatile phenols, terpenes and other aromatic substances were identified in the samples. Among these, aldehydes were found to be the most dominant. (E)-2-Heptenal, nonanal, acetophenone, and 2-ethyl-1-hexanol are thought to be responsible for the off-odors in the water that have the potential to cause off-odors in fish. It was also determined that the amounts of these compounds increases in winter due to lower water temperature. Fish producers should monitor water quality on a regular basis to prevent off-odor compounds that degrade fish quality. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.
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    Comparative Analysis of Different Drying Methods on Strawberry Aroma Compounds via Multi-Criteria Decision-Making Techniques
    (MDPI, 2025) Cengiz, Nurten; Abdulvahitoglu, Asli; Abdulvahitoglu, Adnan
    Food and food safety, as one of the basic issues of human life, has made it necessary to store foods for a long time with the increasing population. One of the oldest and most common methods of extending the shelf life of food products is the drying process. The drying process contributes to the higher quality of foods in terms of physical, chemical, and microbial properties by ensuring that beneficial contents such as vitamins, minerals, and aroma compounds are better preserved. The aroma values of foods, which consist of taste and smell components, gain importance. In foods, the taste is determined by permanent components, while smell is determined by volatile components. The loss of volatile aroma compounds in the strawberry drying process negatively affects product quality. Small changes in aroma compounds can lead to significant differences in product taste. Therefore, strawberry aroma is a critical factor for consumer appeal and commercial success. In this study, the effects of drying methods on the aroma compounds of strawberry fruit were compared with Multi Criteria Decision Making (MCDM) techniques. In this study, PSI-based MCDM techniques were used to make the most appropriate choice among strawberry drying methods. The values of 23 distinct aroma compounds obtained with different drying methods applied to strawberry fruit were analyzed with 7 different MCDM techniques. The calculations gave similar results and these results were combined with the Borda rule. Accordingly, the drying methods with the highest scores were determined as freeze drying.
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    Comparison of phenolic profile and some physicochemical properties of Uzun pistachios as influenced by different harvest period
    (Wiley, 2020) Kelebek, Haşim; Sönmezdağ, Ahmet S.; Güçlü, Gamze; Cengiz, Nurten; Uzlasir, Turkan; Kadiroglu, Pinar; Selli, Serkan
    Pistachios, which are among the top 50 healthiest foods, are rich in antioxidants and are a major source of phenolic compounds known for their related antioxidant benefits. The ripening stage is of paramount importance for food processing since the chemical composition of this fruit is heavily influenced by its level of maturity. For instance, immature pistachios are preferred to be used in desserts, sauces, ice-creams, and chocolate, while mature pistachios are more often consumed as a roasted snack. In this study, the changes in color properties, fatty acids, phenolic compounds, and antioxidant activity at four different maturity periods of the Turkish Uzun pistachio variety were investigated. A total of 13 phenolic compounds were identified and characterized by LC-DAD-ESI/MSn, with a total amount varying between 136 and 210 mg/kg. Catechin, daidzin, and genistin accounted for the highest amount of the total phenolics. The phenolic compounds and antioxidant capacities of the pistachios decreased as the maturation period extended and these two parameters displayed a linear correlation. With regard to fatty acids, Oleic acid had the highest concentration in all the samples, followed by Linoleic and Palmitic acids. The oil yield and fatty acids of pistachio also increased as maturation periods extended in the samples. Practical applications Pistachios have a high nutritional value and many health benefits, with their rich content of phenolic compounds and fatty acids. The ripening period could lead to differences in phenolic compounds and other bioactive properties. The findings of this research could be helpful to determine the optimal maturity index of the pistachios for their usage in specific foods. Thus, it may lead to a decrease in production costs, with use of the most expensive ingredients becoming more efficient.
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    GC-MS-Olfactometric characterization of key odorants in rainbow trout by the application of aroma extract dilution analysis: Understanding locational and seasonal effects
    (Elsevier Sci Ltd, 2023) Cengiz, Nurten; Güçlü, Gamze; Kelebek, Haşim; Selli, Serkan
    The effect of seasonal and regional differences of rainbow trout on its aroma and aroma-active profile was investigated. Solvent-assisted flavor evaporation (SAFE) procedure was employed for the aroma extraction while Gas Chromatography-Mass Spectrometry-Olfactometry (GC-MS-O) and aroma extract dilution analysis (AEDA) were utilized to assess the aroma-active substances. The olfactometric analysis indicated seasonal and regional differences in the aroma-active compounds contributing to the characteristic odours of the trout samples and the compounds were more intense in autumn and winter. The strongest aroma-actives were hexanal (green), acetoin (buttery, green), limonene (citrus), 2-hexanol (green, pungent) and 1-octen-3-ol (oily, mushroom). The findings of this study can provide useful information for the selection of rainbow trout based on the seasons and locations in terms of marketing and consumer preference.