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Öğe Aflatoxin M 1 and ochratoxin A in baby formulae in Turkey: Occurrence and safety evaluation(Elsevier, 2012) Kabak, BülentDuring 2011, 62 samples of baby formulae were checked for aflatoxin M 1 (AFM 1) and ochratoxin A (OTA) by immunoaffinity column (IAC) clean-up and high performance liquid chromatography with fluorescence detection (HPLC-FD). The limits of detection (LOD) and quantification (LOQ) of the analytical method were 0.005 ?g kg -1 and 0.018 ?g kg -1 for AFM 1 and 0.006 ?g kg -1 and 0.021 ?g kg -1 for OTA, respectively. The recovery of AFM 1 from formulae ranged between 84.27% and 88.21% (RSD = 3.54-6.18%), while the mean recoveries of OTA varied from 79.21% to 86.38% (RSD = 4.47-7.11%).Aflatoxin M 1 was detected in five (8%) of formula samples, but at levels below the European legislation limit of 0.025 ?g kg -1, with concentrations ranging from 0.016 to 0.022 ?g kg -1 (mean level: 0.018 ?g kg -1). Ochratoxin A was detected in 12 out of the 62 samples (19.4%), at levels ranging from 0.017 to 0.184 ?g kg -1 (mean level: 0.103 ?g kg -1). None of the samples exceeded the maximum limit for OTA set by European Commission Regulation (0.5 ?g kg -1). The co-occurrence of AFM 1 and OTA was present in only one sample (1.6%). The estimated daily intakes of AFM 1 and OTA through formulae were in the range of 0.08-0.021 ng kg -1 b.w. and 0.034-0.305 ng kg -1 b.w., respectively. On the basis of current knowledge, it can be concluded that there is no considerable risk of AFM 1 and OTA exposure for the Turkish babies and young children. © 2012 Elsevier Ltd.Öğe Aflatoxin M 1 in UHT milk consumed in Turkey and first assessment of its bioaccessibility using an in vitro digestion model(Elsevier, 2012) Kabak, Bülent; Özbey, FatihContamination of milk and dairy products with aflatoxin M 1 (AFM 1) continues to receive increased attention because of its potential health hazard to humans. The first aim of this study was to know the occurrence and levels of AFM 1 in whole UHT milk from main processors in Turkey in order to make a preliminary exposure assessment. A total of 40 milk samples were analysed for AFM 1 using high performance liquid chromatography with fluorescence detection (HPLC-FD) after immunoaffinity column clean-up. Aflatoxin M 1 was detected in 20% of samples at levels ranging from <0.004 to 0.076 ?g l -1. Only two samples contained AFM 1 above the EU limit of 0.05 ?g l -1.The second aim of this study was to determine the bioaccessibility of AFM 1 from milk using an in vitro digestion model. The bioaccessibility of AFM 1 in spiked and naturally contaminated milk samples ranged from 80.5 to 83.8% and from 81.7 to 86.3%, respectively. No difference (P > 0.05) in AFM 1 bioaccessibility was found between spiked and naturally contaminated milk samples. This study also assessed the binding of AFM 1 by six probiotic bacteria under simulated gastrointestinal conditions. A 15.5-31.6% reduction in AFM 1 bioaccessibility was observed in the presence of probiotic bacteria. Based on the results obtained in the present study, the mean daily intake of AFM 1 through milk consumption was estimated as 0.008 ng kg -1 b.w. day -1 for Turkish adults. © 2012 Elsevier Ltd.Öğe Aflatoxins and ochratoxin A in chocolate products in Turkey(Taylor and Francis Ltd., 2019) Kabak, BülentThis survey describes the occurrence and levels of AFs and OTA in chocolate products consumed in Turkey. A total of 130 samples, including bitter chocolate, milk chocolate and chocolate wafers were analysed for these mycotoxins by high-performance liquid chromatography coupled with fluorescence detection (HPLC-FLD). The values of recovery (81–92%) and precision (RSD < 9%) fulfilled the requirements of EC Regulation No. 401/2006. OTA was the most prevalent mycotoxin, with an incidence of 46.7% in bitter chocolate, 22.8% in milk chocolate and 17.4% in chocolate wafers, ranging from 0.18 to 0.75 ?g kg?1. AFs were detected in 13.3% of bitter chocolate, in 19.6% of milk chocolate and in 8.7% of chocolate wafers, in concentrations ranging from 0.15 to 2.04 ?g kg?1.Öğe Aflatoxins in dairy cow feed, raw milk and milk products from Turkey(Taylor and Francis Ltd., 2016) Şahin, Hilal Zeynep; Çelik, Mehtap; Kotay, Seda; Kabak, BülentThis study aims to detect aflatoxins (AFs) in dairy cow feed, milk and milk products using a high-performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method. All the validation parameters met the method performance criteria of the European Union. The samples comprised 76 dairy cow feeds and 205 milk and milk products (including yoghurt and yoghurt-based beverage, ayran). AFs were present in 26.3% of the feed samples. Two feed samples exceeded the maximum limit (ML) of 5 µg kg?1 for AFB1 as established by the EU. Nineteen milk samples (21.1%) contained aflatoxin M1 (AFM1) of which three exceeded the EU ML of 0.05 µg l?1. In addition, only two yoghurt samples and one ayran sample contained AFM1, but the levels were lower than the EU ML. © 2016 Taylor & Francis.Öğe Aflatoxins in hazelnuts and dried figs: Occurrence and exposure assessment(Elsevier Ltd, 2016) Kabak, BülentA total of 300 samples of hazelnuts and dried fig were analysed for the incidence of any aflatoxins (AFs). High-performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method was used to quantify the amounts of AFs. The limit of quantification varied from 0.21 to 0.30 ?g kg?1. No AFs were detected in shells of the hazelnuts, while six raw hazelnut kernel samples (12%) and five roasted hazelnut kernel samples (8.3%) contained AFs ranging from 0.09 to 11.3 ?g kg?1 and from 0.17 to 11.2 ?g kg?1, respectively. Sixteen dried fig samples (12.3%) contained AFs ranging from 0.1 to 28.2 ?g kg?1 and a mean value of 3.8 ?g kg?1. Three hazelnuts and six dried fig samples exceeded the European maximum limits (MLs) of 5 and 2 ?g kg?1 for aflatoxin B1 (AFB1), respectively. The contribution of hazelnuts to AFs exposure is higher than that of dried figs.Öğe An introduction to the traditional fermented foods and beverages of Turkey(2011) Kabak, Bülent; Dobson, Alan D.W.Fermented foods and beverages,whether of plant or animal origin, play an important role in the diet of people in many parts of the world. Fermented foods not only provide important sources of nutrients but have also great potential in maintaining health and preventing diseases. Lactic acid bacteria and yeasts are the major group of microorganisms associated with traditional fermented foods. Many different types of traditional fermented foods and beverages are produced at household level in Anatolia. These include fermented milks (yoghurt, torba yoghurt, kurut, ayran, kefir, koumiss), cereal-based fermented food (tarhana), and non-alcoholic beverage (boza), fermented fruits, and vegetables (turşu, şalgam, hardaliye), and fermented meat (sucuk). However, there are some differences in the preparation of traditional foods and beverages from region to region. The focus of this article is to describe the traditional fermented foods and beverages of Turkey. © Taylor and Francis Group, LLC.Öğe Assessment of the bioaccessibility of aflatoxins from various food matrices using an in vitro digestion model, and the efficacy of probiotic bacteria in reducing bioaccessibility(Elsevier, 2012) Kabak, Bülent; Özbey, FatihThe present study aims to investigate the bioaccessibility of aflatoxin (AF) from various spiked food matrices (peanut, pistachio, hazelnut, dried figs, paprika, wheat and maize) using an in vitro digestion model under fed conditions. In addition, the effectiveness of six probiotic bacteria in reducing AF bioaccessibility was evaluated with an in vitro digestion model. The bioaccessibility of AFs from seven food matrices ranged from 85.1 to 98.1% for aflatoxin B 1 (AFB 1), 83.3 to 91.8% for aflatoxin B 2 (AFB 2), 85.3 to 95.1% for aflatoxin G 1 (AFG 1) and 80.7 to 91.2% for aflatoxin G 2 (AFG 2). The bioaccessibilities of all four compounds were independent of the spiking level and food matrix. The inclusion of probiotic bacteria showed significant (p<0.05) reduction in the bioaccessibility of AFs: up to 35.6% for AFB 1, 35.5% for AFB 2, 31.9% for AFG 1 and 33.6% for AFG 2. AF-binding activity of probiotic bacteria in simulated gastrointestinal conditions was reversible, and 10.3-39.8% of bound AFs were released back into the digestion juices from the bacteria-AF complexes. © 2012 Elsevier Inc.Öğe Biological strategies to counteract the effects of mycotoxins(International Association for Food Protection, 2009) Kabak, Bülent; Dobson, Alan D.W.Mycotoxins are fungal secondary metabolites that if ingested can cause a variety of adverse effects on both humans and animals, ranging from allergic responses to death. Therefore, exposure to mycotoxins should be minimized. A variety of physical, chemical, and biological methods have been developed for decontamination and/or detoxification of mycotoxins from contaminated foods and feeds. This overview details the latest developments in the biological control of both fungal infection and mycotoxin formation and describes the detoxification of many of the most important mycotoxins by microorganisms. This review also addresses the potential for use of microorganisms as mycotoxin binders in the gastrointestinal tract of both humans and animals, thereby reducing the potential deleterious effects of exposure to these toxins. Copyright ©, International Association for Food Protection.Öğe Co-occurrence of aflatoxins and ochratoxin A in cereal flours commercialised in Turkey(Elsevier Ltd, 2015) Müjdeci, Gamze Nur; Özbey, Fatih; Kabak, BülentIn this study, we aim to determine co-occurrence of aflatoxins (AFs) and ochratoxin A (OTA) in cereal flours commercialised in Corum, Turkey. One hundred cereal flours were checked for target fungal metabolites between the years 2011 and 2013. The samples were analysed by high-performance liquid chromatography with fluorescence detection (HPLC-FLD) after immunoaffinity column (IAC) clean-up procedure. The method was successfully validated in accordance to European Union guidelines acceptance criteria for specificity, linearity, sensitivity, trueness and repeatability. All the results are well below the maximum limits specified in the EU legislation. AFs were detected neither wheat flour nor rice flour samples, while 66.7% of maize flours contained AFs with maximum concentration of 1.12 ?g kg?1. OTA was present in 26.7% of wheat flour, 41.7% of maize flour and 18.8% of rice flour samples, with mean levels of 0.247, 0.218 and 0.154 ?g kg?1, respectively. The co-occurence of AFs and OTA was found in 9 maize flour samples.Öğe Detection of aflatoxin M1 in milk and dairy products consumed in Adana, Turkey(Society of Dairy Technology, 2009) Var, Işıl; Kabak, BülentA total of 70 dairy products consisting of 20 sterilized milk, 10 butter, 20 white cheese and 20 Kashar cheese samples were analysed for aflatoxin M 1(AFM1) by enzyme-linked immunosorbent assay (ELISA). The detection limit was 5 ng/L for milk and 25 ng/kg for butter, white cheese and Kashar cheese. Of the 70 dairy products analysed, AFM1 in 49 samples (70%) was found to range from 10 to 388 ng/kg. Moreover, AFM1 levels in three samples of milk, two samples of butter, one sample of white cheese and one sample of Kashar cheese were found to be higher than the Turkish legal limits.Öğe Determination of 115 pesticide residues in oranges by high-performance liquid chromatography-triple-quadrupole mass spectrometry in combination with QuEChERS method(Academic Press Inc., 2015) Gölge, Özgür; Kabak, BülentThe present study aims to determine 115 pesticide residues in 400 commercially available orange samples in Adana, Mersin and Hatay provinces of Turkey. Pesticide determination was carried out using liquid chromatography–tandem mass spectrometry (LC–MS/MS) method. A modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation technique involved acetonitrile-based extraction of the samples, and followed by dispersive solid-phase extraction (d-SPE) cleanup using primary–secondary amine (PSA), was used prior to LC–MS/MS analysis. The method showed satisfactory linearity, specificity, recovery and precision. The limit of detection (LOD) and limit of quantification (LOQ) for target analytes were in the range of 0.001–0.011 mg kg?1 and 0.002–0.030 mg kg?1, respectively. The expanded measurement uncertainty was not higher than 45% for all target analytes. Only one insecticide and two fungicides were detected individually in a total of 30 orange samples. Chlorpyrifos was the predominant pesticide at levels ranging from 0.01 to 0.09 mg kg?1, while imazalil was detected in 3 samples (0.09–0.48 mg kg?1) and azoxystrobin was found in only 2 samples (0.02 and 0.03 mg kg?1).Öğe Determination of 355 Pesticides in Lemon and Lemon Juice by LC-MS/MS and GC-MS/MS(MDPI, 2023) Aslantaş, Şule; Gölge, Özgür; González-Curbelo, Miguel Ángel; Kabak, BülentAbstract: While pesticides have become a primary tool in modern agriculture, these compounds remain a high priority on the list of consumer concerns regarding food safety. The use of pesticides in the production and post-harvesting of lemon fruits is widely used to ensure agricultural yield and fruit quality. Therefore, monitoring studies on citrus fruits to enforce regulatory compliance and ensure food safety is in great demand. The aim of this study was to monitor multi-class pesticide residues in lemon fruits commercialized in Turkey. The transmission of residues that existed on the outer surface of the fruit into its juice was also studied. Whole fruits and lemon juice samples were prepared using the quick, easy, cheap, effective, rugged and safe (QuEChERS) methodology prior to analysis. For the screening and quantification of 355 pesticide residues, liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) were used. The analytical method has been shown to have a sufficiently low limit of quantification with respect to current maximum residue limits (MRLs) for all target analytes. The obtained recovery and precision parameters fulfilled the requirements in DG SANTE guidelines. The in-house validated analytical method was then applied for the determination of 355 pesticide substances in 100 whole fruit samples and their juices. Sixteen different residues were detected in 43% of lemon fruits, whereas 57 lemon samples were pesticide-free. The MRLs exceedances were recorded in 29 lemon samples. The most frequently detected (17%) pesticide in lemon fruits was chlorpyrifos-methyl, with a range of 0.013–0.098 mg kg?1 . A lower frequency was detected for metamitron (10%, 0.027–0.118 mg kg?1 ), buprofezin (9%, 0.023–0.076 mg kg?1 ), pyriproxyfen (9%, 0.021–0.102 mg kg?1 ) and malathion (7%, 0.100–0.482 mg kg?1 ) in whole fruits. However, none of the pesticide residues were detected in lemon juice samples. These results showed that target analytes are unable to penetrate the lemon exocarp and/or endocarp. Keywords: food safÖğe Determination of aflatoxins and ochratoxin A in retail cereal products from Turkey by high performance liquid chromatography with fluorescence detection(Elsevier Ltd, 2012) Kabak, BülentIn this study, a total of 110 retail cereal products from Turkey were analysed for aflatoxins (AFB1, AFB2, AFG1 and AFG2) and ochratoxin A (OTA). The mycotoxins were determined by liquid–solid extraction, immunoaffinity column clean-up and high performance liquid chromatography with fluorescence detection (HPLC-FD). Recoveries (83.9–92%) and both intra-day and inter-day repeatability (RSD < 12) of the method, meet the performance criteria set by EC regulation No. 401/2006 for the determination of the levels of mycotoxins in foodstuffs. OTA was the most prevalent toxin, with an incidence of 43.6% (range = 0.066–1.125 ?g kg?1), but at levels below the European legislation limit of 3 ?g kg?1. Aflatoxins were found in 27 of 110 analysed samples: twenty-seven samples with AFB1, fourteen samples with AFB2, seven samples with AFG1 and two samples with AFG2. The ranges for positive samples were 0.052–0.233 ?g AFB1 kg?1, 0.022–0.044 ?g AFB2 kg?1, 0.053–0.149 ?g AFG1 kg?1 and 0.033–0.037 ?g AFG2 kg?1. The co-occurrence of AFB1 and OTA was observed in 14.6% of the samples. This is the first study concerning the simultaneous occurrence of aflatoxins and OTA in retail cereal products from Turkey.Öğe Determination of aflatoxins in walnut sujuk and Turkish delight by HPLC-FLD method(Elsevier Ltd, 2016) Gölge, Özgür; Hepsağ, Fatma; Kabak, BülentThis study aims to assess the risk of aflatoxins (AFs) in traditional confectionery products (walnut sujuk and Turkish delight) of Turkey. A high performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method was used for the determination of AFs. Evaluation of the method showed good selectivity, linearity, recovery and precision. The limit of quantification (LOQ) ranged from 0.106 to 0.374?gkg-1. The expanded measurement uncertainty was less than 40% for all target analytes. The validated method was successfully applied to the determination of AFs in 112 traditional confectionery products containing nuts (hazelnuts and walnuts). AFs were detected in 43.8% of walnuts and 60.9% of hazelnuts used as ingredients in walnut sujuk and Turkish delight and at levels ranging from 0.58 to 15.2?gkg-1 and 0.43-63.4?gkg-1, respectively. This means that AFs levels in walnut sujuk and Turkish delight were up to levels of 6.1 and 9.5?gkg-1, respectively. Six walnut samples and twenty-one hazelnut samples were above the EU maximum limits (MLs) of 2 and 5?gkg-1 for aflatoxin B1 (AFB1), respectively. © 2015 Elsevier Ltd.Öğe Dietary intake of sorbic and benzoic acids from tomato ketchup for adults and children in Turkey(Birkhauser Verlag AG, 2015) Gölge, Özgür; Hepsağ, Fatma; Kabak, BülentThis report aims to determine levels and dietary intake of sorbic and benzoic acids from tomato ketchup consumed in Turkey. During the period from September 2013 to October 2014, a total of 63 tomato ketchup samples were analysed by high performance liquid chromatography coupled with photodiode array detection (HPLC–PDA). The analytical method was successfully validated in terms of linearity, sensitivity, recovery, repeatability, within-laboratory reproducibility and measurement uncertainty. Sorbic and benzoic acids were detected in 63.5 and 52.4 % of ketchup samples at levels ranging from 37.5 to 1419 mg kg?1, and from 98.5 to 1284 mg kg?1, respectively. Fifteen tomato ketchup samples were above the European maximum levels (MLs) of 1000 mg kg?1 for the sum of sorbic acid—sorbates and benzoic acid—benzoates in non-emulsified sauces. The estimated daily intakes of sorbic and benzoic acids through tomato ketchup were 0.005 and 0.004 mg kg?1 b.w. for adults, and 0.012 and 0.01 mg kg?1 b.w. for children, respectively.Öğe Effects of probiotic bacteria on the bioaccessibility of aflatoxin B1 and ochratoxin A using an in vitro digestion model under fed conditions(Taylor and Francis, 2009) Kabak, Bülent; Brandon, Esther F.A.; Var, Işıl; Blokland, Marco H.; Sips, Adriënne J.A.M.In the present study, we aimed at determining the release of aflatoxin B1 (AFB1) and ochratoxin A (OTA) from different food products in the gastro-intestinal tract in the absence and presence of probiotics, a possible adsorbent. The average bioaccessibility of AFB1 and OTA without probiotics was about 90%, and 30%, respectively, depending on several factors, such as food product, contamination level, compound and type of contamination (spiked versus naturally contaminated). The six probiotic bacteria showed varying binding capacity to AFB1 and OTA depending on the bacterial strain, toxin studied, type of food and contamination level. A reduction to a maximum of 37% and 73% as observed for the bioaccessibility of AFB1 and OTA in the presence of probiotic bacteria, respectively. This is the first report on the effect of probiotic bacteria on reducing the fraction of mycotoxins available for absorption in the gastrointestinal tract from different food products.Öğe Evaluation of QuEChERS sample preparation and liquid chromatography-triple-quadrupole mass spectrometry method for the determination of 109 pesticide residues in tomatoes(Elsevier Ltd, 2015) Gölge, Özgür; Kabak, BülentA multiresidue method based on modified QuEChERS (quick, easy, cheap, effective, rugged and safe) sample preparation, followed by liquid chromatography tandem mass spectrometry (LC–MS/MS) was developed and validated for the determination of 109 selected multiclass pesticides in tomatoes. The recovery yields ranged from 77.1% to 113.2%, with repeatabilities of 4.4–19.2% and within-laboratory reproducibilities of 7.1–18.4%. The limit of detections (LODs) for target analytes in tomato extract were between 0.5 and 10.8 ?g kg?1, and the limit of quantifications (LOQs) were between 1.3 and 30.4 ?g kg?1. The expanded measurement uncertainty was not higher than 30% for all target analytes. The method has been successfully applied to the analysis of 345 tomato samples obtained from local markets and tomato traders. Residues of acetamiprid, azoxystrobin and triadimefon were identified and measured in 9.6% of tomato samples, ranging from 0.015 to 0.37 mg kg?1.Öğe Factors affecting the removal of aflatoxin M1 from food model by Lactobacillus and Bifidobacterium strains(Taylor and Francis, 2008) Kabak, Bülent; Var, IşılThis paper describes the ability of six dairy strains of Lactobacillus and Bifidobacterium to remove aflatoxin M1 (AFM1) from phosphate-buffered saline (PBS) and reconstituted milk. Bacteria were incubated in both PBS and reconstituted milk containing 5, 10 and 20 ng mL-1 for 0, 4 and 24 h at 37°C. After centrifugation the concentration of AFM1 was determined in the supernatant fraction using high-performance liquid chromatography. The binding abilities of AFM1 by viable (108 CFU mL-1) and heat-killed Lactobacillus and Bifidobacterium strains in PBS ranged from 10.22 to 26.65% and 14.04 to 28.97%, respectively. Similarly, AFM1-binding capacity in reconstituted milk was found to range from 7.85 to 25.94% and from 12.85 to 27.31% for viable and heat-killed bacteria, respectively within 4 h. While B. bifidum Bb 13 was the best binder, the poorest removal was achieved by L. acidophilus NCC 68. Binding was reversible, and a small proportion of AFM1 was released back into the solution. The toxin concentration and incubation period had no effect on the removal of AFM1 by bacteria both in PBS and reconstituted milk.Öğe First report: Exposure estimates to ochratoxin a through wheat bread and rice intake in Turkey(Academic Press, 2016) Gölge, Özgür; Kabak, BülentA total of 160 samples of fresh wheat bread and rice from Turkey were analysed for the presence of ochratoxin A (OTA). The samples were analysed using a high performance liquid chromatography coupled with fluorescence detection (HPLC-FLD). The method was previously validated and showed good selectivity, linearity, sensitivity and accuracy. The uncertainty associated with the analytical method was less than 20%. OTA was found in 9.8% of wheat bread (10 out of 102 samples) and 5.2% of rice (3 out of 58 samples) at levels ranging fromÖğe Health risk assessment of selected pesticide residues in green pepper and cucumber(Elsevier Ltd, 2018) Gölge, Özgür; Hepsağ, Fatma; Kabak, BülentThis report describes levels of 170 pesticide residues in green pepper and cucumber marketed in Turkey. The report also comprises the outcome of the consumer risk assessment of selected pesticides. In total, 725 samples of vegetables were analysed for residues of 170 distinct pesticides by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The in-house validation data fulfilled the requirements of the European SANTE/11945/2015 Guideline. The limit of quantifications (LOQs) varied from 0.003 to 0.016 mg kg-1. Recoveries ranged between 80.5 and 118.2%, with inter-day precisions of 0.7–19% relative standard deviation (RSD). The expanded measurement uncertainty for individual pesticides ranged from 10.4 to 42.4%. Overall, 12.9% of green peppers and 13.5% of cucumbers contained at least one detectable residue, but the levels were below the EU legal limits. For adults, the Hazard Quotients (HQs) for identified pesticides in green peppers and cucumbers ranged from 0.0003 to 0.0143%, and from 0.0001 to 0.0103%, respectively. Propamocarb and chlorpyrifos were the major contributors to hazard index (HI) for green pepper and cucumber, respectively. The results showed that there is no reason to be concerned about cumulative exposure to residues from green pepper and cucumbers for Turkish population. © 2018 Elsevier Ltd
