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Öğe Determination of 16 European Priority Polycyclic Aromatic Hydrocarbons in Doner Kebab Varieties Cooked Under Different Heating Sources(MDPI, 2024) Akkaya, Esra; Colak, Hilal; Hampikyan, Hamparsun; Sancar, Burcu Cakmak; Akhan, Meryem; Engin, Ayse Seray; Cetin, OmerDoner kebab is a traditional Turkish meat product produced from lamb, beef or poultry meat seasoned with a blend of spices such as salt, black pepper, cumin, thyme and/or sauces. The aim of this study was to determine 16 EU priority polycyclic aromatic hydrocarbons (PAHs) in doner kebabs cooked under four different heating sources (electricity, open gas, wood and charcoal grilling). For this purpose, 200 meat doner and 200 chicken doner kebab samples were obtained randomly from various buffets and restaurants located in Istanbul and analyzed by means of GC-MS. According to the results, benzo[a]pyrene and PAH4 levels, which are important PAH compounds as biomarkers, were significantly higher in chicken doner than in meat doner (p < 0.05). The highest occurrence of benzo[a]pyrene and PAH4 in meat and chicken doner samples was in the charcoal heating source, whereas the lowest occurrence was detected in electric grilling. In terms of all PAH compounds, cooking with an electric heating source caused the formation of fewer PAH compounds in doner kebab samples. Consequently, the fat content of fatty meat products such as doner kebab should be reduced, the contact of fat with the heating source (especially flame) and dripping of fat to the source should be prevented and overcooking of meat should be avoided.Öğe DETERMINATION OF MICROBIOLOGICAL QUALITY AND HEAVY METAL RESIDUAL LEVELS IN BOTTLED SPRING AND NATURAL MINE L WATERS(Parlar Scientific Publications (P S P), 2021) Akhan, Meryem; Akkaya, Esra; Ergun, Ozer; Hampikyan, Hamparsun; Colak, Hilal; Bingol, Enver BarisWater is a vital food material for humans and other living things to survive. Recent developments in various industrial sectors, urbanization and the spread of agriculture based on modern techniques have resulted in increased contamination of water with heavy metals and microbial agents. This study was conducted to investigate the concentrations of selected heavy metals in spring and natural mineral waters and to determine the microbiological qualities of them. For this purpose, 200 spring and 200 natural mineral waters were collected and analyzed microbilogically and chemically for the residual quantities of Pb, As, Hg, Cd, Cu using 1CP-MS technique. Pb, As and Cu concentrations were higher to the limit values of the regulations in 13 (6.5%) of spring and in 72 (36%) of natural mineral waters. Moreover, TVBC was found to be above the limit values in 33 (8.25%) of the analyzed samples, while any conforms, fecal coliforms or E.coli were detected. As a result, it's important to carry out routine microbiological screening of waters on the basis of welding, filling units and filling containers, continuously monitoring of heavy metals in water samples and to take preventive measures to prohibit environmental pollution by heavy metals' contamination in order to protect the public health.Öğe Effect of Thermosonication on Amino Acids, Phenolic Compounds, Sensory Properties and Microbial Quality in Freshly Squeezed Verjuice(MDPI, 2023) Col, Basak Gokce; Akhan, Meryem; Sancar, Burcu Cakmak; Turkol, Melikenur; Yikmis, Seydi; Hecer, CananThermosonication is a process that can be used as an alternative to thermal pasteurization by combining mild temperature and ultrasound treatments. This study evaluated the effects of verjuice on the thermosonication process and its bioactive values modeled with the RSM (response surface method). The bioactive components of verjuice were found to increase with high predictive values. Additionally, the presence and amounts of 20 free amino acids in C-VJ (untreated verjuice), P-VJ (thermally pasteurized verjuice) and TS-VJ (thermosonicated verjuice) samples were investigated. Significant (p < 0.05) differences were detected among C-VJ, P-VJ and TS-VJ samples in all free amino acid values except methionine. Although 17 free amino acids were detected at various concentrations, glycine, taurine and cystine were not found in any samples. Thirteen phenolic filters in C-VJ, P-VJ and TS-VJ samples were also examined in this study. Eight phenolic donors with various abilities were detected in the C-VJ sample, along with nine phenolic acceptors in the P-VJ sample and eleven phenolic contents in the TS-VJ sample. The content of phenolic products in the TS-VJ sample increased by 37.5% compared to the C-VJ techniques and by 22.22% compared to the P-VJ techniques. Thermosonication did not significantly affect color and physiochemical values. Panelists generally appreciated the effects of thermosonication. It is concluded that the thermosonication process is a good alternative to thermal pasteurization. The results of this study provide essential data for future in vivo studies and show that the bioactive values of verjuice can be increased by using the thermosonication process.Öğe Enhancing the Functionality and shelf life of poppy sherbet by optimizing ultrasound and propolis using response surface methodology: Impact on phenolic compounds, organic acids, sugar components, and sensory characteristics(Elsevier, 2025) Akhan, Meryem; Turkol, Melikenur; Yikmis, Seydi; Sancar, Burcu cakmak; Col, Basak Gokce; Khalid, Muhammad Zubair; Moreno, AndresPoppy plant, scientifically known as Papaver rhoeas L., is an annual herbaceous wild plant. Propolis boasts numerous health advantages. This study aimed to optimize a novel functional beverage enriched with propolis and enhanced with ultrasound technology using Response Surface Methodology (RSM). Optimization focused on total bioactivities and general acceptability, determining optimal amounts of propolis extract (53.33 mg/100 mL), ultrasound time (7.56 min), and ultrasound amplitude (75.76%) to create the optimized ultrasound-treated propolis poppy sherbet (UTP). The optimized UTP had a high total phenolic content (552.25 mg GAE/L), a DPPH value of 9.26 mu mol trolox/g, a total antioxidant capacity of 42.16 mg Cy-3-gly/mL (Cyanidine-3-glycoside/mL), and a general acceptability score of 7.87. The consistency between experimental results and RSM predictions confirmed the approach's accuracy. After 21 days, bioactive components, phenolic compounds, organic acids, sugars, and sensory properties were assessed. UTP showed enhanced bioactive components and sensory properties compared to standard poppy sherbet, with higher glucose and turanose among 17 phenolic compounds. However, sensory attributes like color, aroma, and taste significantly declined over storage. As a result, these findings contribute to the development of functional beverages and the further enhancement of poppy-related foods using RSM optimization.Öğe İçme Suları ve Gıdalarda Mikroplastikler(2022) Akhan, Meryem; Sancar, Burcu Çakmak; Öztürk, Muhsin; Ergün, ÖzerDünya üzerinde kalabalık nüfuslu ve sanayileşmiş bölgelerde karasal kaynaklardan gelen çok fazla miktarda plastik çöpler bulunmaktadır. Öyle ki, bilim insanları içinde bulunduğumuz Antroposen dönemde “Plastik Çağ’a” girildiğini ifade etmişlerdir. Hava, rüzgâr ve akarsu hareketleri gibi doğal yollarla çevreye ve su kaynaklarına bulaşabilen mikro plastikler 5 mm’den küçük veya 5 mm büyüklüğünde olan suda çözünmeyen katı polimer partiküller olarak tanımlanmışlardır. Mikro plastikler büyüklüklerine göre; küçük mikro plastikler (<1 mm) ve büyük (2-5 mm) olmak üzere iki sınıfa ayrılırlar. Birçok bilim insanı mikro plastiklerin deniz ve tatlı su ekosistemlerindeki çeşitli su ürünlerini (istiridyeler, fulmarlar, midye, deniz ve tatlı su balıkları vb.) etkilediğini bildirmişlerdir. Ayrıca deniz, göl ve kaya tuzlarında mikro plastiklerin kontaminasyon seviyesi bazı araştırmacılar tarafından 7-681 madde/kg olarak belirlenmiştir. Nano ve mikro plastikler insan besin zincirine özellikle su ürünleri ile beslenme yoluyla ve/veya inhalasyon yoluyla girebilmektedir. Bisfenol A (BPA) ve fitalatlar yutulduğunda veya solunduğunda insan sağlığına zarar verebilecek endokrin bozucular olduğu kanıtlanmıştır. Ancak mikro plastiklerin insan sağlığı üzerinde doğrudan toksik bir etkiye sahip olduğunu kesin olarak belirlemenin zor olduğu bildirilmektedir. ABD, İngiltere, Kanada ve Avustralya başta olmak üzere 2018 yılı itibariyle de neredeyse tüm ülkelerde kozmetiklere eklenen mikro boncukların kullanılması yasaklanmıştır. Sularda mikro plastik kirliliğini önlemede; atık su arıtma tesislerine bir Ultrafiltrasyon ünitesi eklenmesinin ve çamaşır makinalarının sentetik tekstil iplikçiklerini tutacak bir üniteyle donatılmasının mikro plastik sorununu önemli bir ölçüde çözeceği düşünülmektedir.Öğe İzmir Tulum Peynirinde Koagülaz Pozitif Stafilokokların Yaygınlığı, Antibiyotik Direnci ve Biyofilm Oluşumu(Gültekin ÖZDEMİR, 2025) Çöl, Başak Gökçe; Yalçın, Semiha; Çakmak Sancar, Burcu; Akhan, Meryem; Sağlam, Kübra; Yıkmış, SeydiKoagülaz-pozitif stafilokoklar (CPS), stafilokokal gıda zehirlenmelerinde başlıca bakteriyel etkenler olup, insanlarda ve hayvanlarda enfeksiyonlara neden olarak önemli bir halk sağlığı riski oluştururlar. Bu çalışmada, İzmir ilindeki çeşitli perakende satış noktalarından toplam 100 İzmir Tulum Peyniri örneği toplanmıştır. Peynir örneklerinden standart kültürel yöntemler kullanılarak CPS izolatları elde edilmiştir. CPS izolatlarının fenotipik antibiyotik dirençleri agar disk difüzyon testi ile, biyofilm oluşturma kapasiteleri ise kolorimetrik yöntemle belirlenmiştir. Çalışmada, analiz edilen 100 İzmir Tulum Peyniri örneğinin 30'unda (%30) CPS izole edilmiş ve bu örneklerin 27’sinde (%27), Türk Gıda Kodeksi Mikrobiyolojik Kriterler Yönetmeliği'nde belirtilen maksimum CPS sınırı olan 10³ CFU/g’nin üzerinde CPS düzeyleri tespit edilmiştir. Antimikrobiyal direnç testi sonucunda, 30 CPS izolatının %90’ının penisiline dirençli olduğu belirlenmiştir; diğer yaygın antibiyotiklere direnç oranları ise %83,3 klindamisin, %56,7 siprofloksasin ve %53,3 tetrasiklin olarak tespit edilmiştir. Ayrıca, izolatların %76,7’sinin çoklu ilaç direncine sahip olduğu, yani farklı antibiyotiklerle kolayca öldürülemediği ve bu durumun tedavi seçeneklerini sınırladığı belirlenmiştir. Bunun yanı sıra, CPS izolatlarının %83,3’ünün biyofilm oluşturma kapasitesine sahip olduğu tespit edilerek, bunun gıda güvenliği üzerindeki olumsuz etkisi vurgulanmıştır. Elde edilen bulgular, süt ürünlerinde biyofilm oluşumuna karşı yenilikçi stratejilerin yanı sıra daha sıkı hijyen protokolleri ve kontrollü antibiyotik kullanımının gerekliliğini ortaya koymaktadır.Öğe Monitoring of Ochratoxin A Occurrence and Dietary Intake in Tarhana, a Fermented Cereal-Based Product(MDPI, 2025) Akkaya, Esra; Akhan, Meryem; Sancar, Burcu Cakmak; Hampikyan, Hamparsun; Engin, Ayse Seray; Cetin, Omer; Bingol, Enver BarisThe aim of this study was to determine the mold and ochratoxin A (OTA) contamination of tarhana, a traditional product widely consumed in Turkish cuisine. For this purpose, a total of 350 tarhana samples (homemade and industrially produced) were randomly collected from retail stores, markets, and bazaars in different regions of T & uuml;rkiye and analyzed by means of LC-MS/MS for the occurrence of OTA. According to the results, OTA was detected in 36 of 150 (24%) industrially produced tarhana samples, with a concentration range of 0.12-2.34 mu g/kg, while 118 of 200 (59%) homemade tarhana samples contained OTA, with the range from 0.16 to 4.15 mu g/kg. Only 8 of 350 (4%) homemade tarhana samples were found to be above the maximum permissible limit (3.0 mu g/kg) for OTA. The mold contamination was found to be higher in homemade tarhana (3.756 log CFU/g) than in the industrially produced samples (2.742 log CFU/g). The estimated weekly intake values of OTA with tarhana consumption were well below the provisional tolerable weekly intake values for both industrially produced and homemade tarhana samples, even when consumed every day of the week, indicating that dietary intake of OTA through tarhana consumption does not pose a health risk. In conclusion, optimizing the fermentation and drying conditions applied during tarhana production and ensuring proper hygiene conditions can help to reduce the risk of OTA contamination. Moreover, monitoring and testing the OTA levels in tarhana on a regular basis can also ensure the food safety of this product.Öğe Pesticide residues in vegetables and fruits from Istanbul by LC-MS/MS(2022) Çakmak Sancar, Burcu; Akhan, Meryem; Öztürk, Muhsin; Ergün, ÖzerSelected pesticide active ingredients are used in various stages of production of fruits and vegetables in Turkey for the purpose of pest control. Due to their harm to humans, animals and the environment, pesticide active ingredients and their residue limits were determined by legal regulations. The aim of this study was to determine and highlight the pesticide residue risk in fruits and vegetables sold in markets and greengrocers and widely consumed in Istanbul, one of the most populated cities in Turkey. 393 pesticide active ingredients in 100 fruit and vegetable samples (tomatoes, green peppers, cucumbers, strawberries and apples in total) were screened using liquid chromatography coupled to mass spectrometry (LC–MS/MS) with Quick Easy Cheap Effective Rugged and Safe (QuEChERS) sample preparation method. The mean recoveries of the pesticides were between 76.5 % and 115.5 %, LOQ for them was 0.01 mg kg-1. Pesticide residue was detected in 43% of the samples. A total of 7 (7%) samples contained pesticide residues above maximum residue limit (MRL). While pesticide residues were detected above MRL in tomato, strawberry and cucumber samples; no pesticide residues were found above MRL in pepper and apple samples. In the samples analyzed, 42 different pesticide residues were detected, the most detected pesticide active substance in the samples examined was Acetamiprid. Phorate Sulfone, one of the banned pesticides, was detected in a strawberry sample.Öğe Use of Microbial Pigments as Colorants in Foods(İstanbul Gelişim Üniversitesi, 2023) Çakmak Sancar, Burcu; Öztürk, Muhsin; Akhan, Meryem; Ergün, ÖzerToday, the widespread negative opinions of consumers about synthetic food colorings have increased the demand for colorants derived from natural sources. Naturally derived colorants are obtained from plants, animals, and microorganisms and are referred to as biorecolorants. Among these, pigments obtained from microorganisms are preferred because of their beneficial effects on health and various advantages in production. Various microorganisms (Monascus, Flavobacterium, Bacillus, Paracoccus, Streptomyces, Penicillium, Rhodotarula, Brevibacterium, etc.) are capable of producing pigments; ?-carotene, arpink red, riboflavin, monascus pigment, prodigiosin, and lycopene are the main pigments produced. Microbial pigments have various advantages such as easy extraction, low production costs, no raw material problems and environmental friendliness. However, some microbial pigments also have disadvantages, such as being insoluble in water, showing color changes under different pH conditions, causing taste changes, and having a more limited color range. This review provides basic information about the color pigments of microorganisms used in foods.
