Kabak B.,Hitit University |
Dobson A.D.W.,University College Cork
Critical Reviews in Food Science and Nutrition | Year: 2011
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.
Kocak C.,Hitit University
Applied Soft Computing Journal | Year: 2017
Within classic time series approaches, a time series model can be studied under 3 groups, namely AR (autoregressive model), MA (moving averages model) and ARMA (autoregressive moving averages model). On the other hand, solutions are based mostly on fuzzy AR time series models in the fuzzy time series literature. However, just a few fuzzy ARMA time series models have proposed until now. Fuzzy AR time series models have been divided into two groups named first order and high order models in the literature, highlighting the impact of model degree on forecast performance. However, model structure has been disregarded in these fuzzy AR models. Therefore, it is necessary to eliminate the model specification error arising from not utilizing of MA variables in the fuzzy time series approaches. For this reason, a new high order fuzzy ARMA(p,q) time series solution algorithm based on fuzzy logic group relations including fuzzy MA variables along with fuzzy AR variables has been proposed in this study. The main purpose of this article is to show that the forecast performance can be significantly improved when the deficiency of not utilizing MA variables. The other aim is also to show that the proposed method is better than the other fuzzy ARMA time series models in the literature from the point of forecast performance. Therefore, the new proposed method has been compared regarding forecast performance against some methods commonly used in literature by applying them on gold prices in Turkey, Istanbul Stock Exchange (IMKB) and the Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX). © 2017 Elsevier B.V.
Kabak B.,Hitit University
Food Control | Year: 2012
During 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 μg kg -1 and 0.018 μg kg -1 for AFM 1 and 0.006 μg kg -1 and 0.021 μg 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 μg kg -1, with concentrations ranging from 0.016 to 0.022 μg kg -1 (mean level: 0.018 μg kg -1). Ochratoxin A was detected in 12 out of the 62 samples (19.4%), at levels ranging from 0.017 to 0.184 μg kg -1 (mean level: 0.103 μg kg -1). None of the samples exceeded the maximum limit for OTA set by European Commission Regulation (0.5 μg 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.
Kabak B.,Hitit University
Food Control | Year: 2012
In this study, a total of 110 retail cereal products from Turkey were analysed for aflatoxins (AFB 1, AFB 2, AFG 1 and AFG 2) 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 μg kg -1), but at levels below the European legislation limit of 3 μg kg -1. Aflatoxins were found in 27 of 110 analysed samples: twenty-seven samples with AFB 1, fourteen samples with AFB 2, seven samples with AFG 1 and two samples with AFG 2. The ranges for positive samples were 0.052-0.233 μg AFB 1 kg -1, 0.022-0.044 μg AFB 2 kg -1, 0.053-0.149 μg AFG 1 kg -1 and 0.033-0.037 μg AFG 2 kg -1. The co-occurrence of AFB 1 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. © 2012 Elsevier Ltd.
Ozbey F.,Hitit University |
Kabak B.,Hitit University
Food Control | Year: 2012
The present study aims to determine the co-occurrence of aflatoxins (AFs) and ochratoxin A (OTA) in spices marketed in Turkey. During the period from November 2010 to August 2011, 105 samples of spices were checked for targeted mycotoxins. The mycotoxins were determined by high-performance liquid chromatography coupled with fluorescence detection (HPLC-FD) after immunoaffinity column (IAC) clean-up. The method was validated for selectivity, sensitivity, accuracy and repeatability as relative standard deviation (RSD). Good recoveries (80.7-95.7%) were obtained for mycotoxins in each food matrix, with RSD values lower than 15%.Aflatoxins were detected in 79.2% of red chilli flake, 63.6% of red chilli powder, 30.4% of black pepper powder and 21.1% of cumin samples, while none of the cinnamon powder samples contained AFs at detectable levels. Four red chilli flake and three red chilli powder samples were above the EU regulatory limit of 5μgkg -1 for AFB 1. OTA was found in 75% of red chilli flake, 54.5% of red chilli powder, 17.4% of black pepper powder, with four red chilli flake and three red chilli powder samples exceeding EU limit of 30μgkg -1. No OTA was found in cinnamon powder samples, while detectable levels of OTA were found in only one cumin sample. The co-occurrence of AFB 1 and OTA was detected in 62.5% of red chilli flake, 40.9% of red chilli powder and 4.3% of black pepper powder samples. This study reports for the first time the natural co-occurrence of AFs and OTA in spices from Turkey. © 2012 Elsevier Ltd.
Bahceci K.S.,Hitit University
International Journal of Food Science and Technology | Year: 2012
The central composite design with a quadratic model was used to investigate the effect of temperature (20-40°C) and transmembrane pressure (TMP) (100-300kPa) as well as pretreatment with gelatin and bentonite (0:0-300:1500mgL -1) on permeate flux and fouling resistance during ultrafiltration of apple juice. The changes in some physicochemical properties were also investigated. Pretreatment of apple juice with gelatin and bentonite and an increase in the temperature and TMP significantly improved the permeate flux. In general, physicochemical properties of apple juice other than polyphenolics were not affected by the applied parameters. Using 150mgL -1 of gelatin and 750mgL -1 of bentonite for fining significantly reduced the total phenolic content and so did the fouling resistance. Fouling resistance also decreased with increasing temperature, and increasing pressure increased the fouling resistance. © 2011 Institute of Food Science and Technology.
Kaya N.,Hitit University
Liquid Crystals | Year: 2011
Guest-host liquid crystal displays have been widely utilised because of their many advantages such as colour, wide viewing angle and high brightness. For practical guest-host applications, it is important to choose dyes with a high ability of orientation in the liquid crystal matrix. In this work, two different nematic liquid crystals (E8 and ZLI-1132) were separately doped with three different dyes (1,2-, 1,4- and 2,6-diaminoanthraquinone). Their solubilities, textures, phase transition temperatures and order parameters were determined. At the second stage, single-walled carbon nanotubes (CNTs) were added (0.05% m/m) to these solutions and the same parameters (except solubilities) were studied again. The highest solubility and order parameter values were attained with 1,4- diaminoanthraquinone dye in ZLI-1132 nematic host. When CNTs in a small amount were added to the dye mixtures as co-dopant, the further increases in order parameters (S) were observed in mixtures with low S values. These dyes and CNTs did not significantly destabilise the mesomorphic phase of nematic hosts. An appreciable change in textures was not observed with addition of dopant(s). © 2011 Taylor & Francis.
Caliskan S.,Hitit University
International Journal of Heat and Mass Transfer | Year: 2013
An experimental study was conducted to investigate heat transfer and flow characteristics under impingement of a multiple circular jet array with perforated rib surfaces (PRS) and solid rib surfaces (SRS). Heat transfer results were obtained using an infrared thermal imaging technique. Velocity measurements were made with a Laser-Doppler Anemometry (LDA) system. The heat transfer results of the rib surfaces are compared with those of a smooth plate. Best heat transfer performance was obtained with the PRS arrangements. The presence of rib perforation produces higher heat transfer coefficients than the smooth plate and SRS surfaces. Correlations have been developed for the average Nusselt number for the perforated rib surfaces based on projected and total area. The velocity measurements were obtained for the case where the jet-to-plate distances at H/d equal to 2, 4, 8 and at a Reynolds number of 10,000. Positions of maximum radial and axial velocities and Reynolds stress distributions have been determined for PRS, SRS and smooth plates. For some locations, the production of turbulence kinetic energy and radial velocities are higher for the PRS surfaces as compared to SRS and smooth surfaces. © 2013 Elsevier Ltd. All rights reserved.
Duman N.B.,Hitit University
Pakistan Journal of Medical Sciences | Year: 2015
Objective: This prospective study was undertaken to assess the frequency of gestational diabetes mellitus (GDM) and the associated risk factors during pregnancy.Methods: The sample consisted of 650 pregnant women who had no known risk factors for GDM and were followed-up at the Outpatient Clinic for Pregnant Women, Corum State Hospital between March 2009 and June 2010. The data were expressed as percentage, arithmetic mean, standard deviation and chi-square test.Results: Of the 650 pregnant women, 45 were diagnosed with GDM during the study period (6.9%). A statistically significant correlation between GDM and advanced age, family history, and body mass index was found, while no significant correlations existed between GDM and the frequency of pregnancy, number of pregnancy, parity, and number of live births.Conclusion: Advanced age, high body mass index and family history of diabetes mellitus emerged as risk factors for GDM in our study. © 2015, Professional Medical Publications. All rights reserved.
News Article | October 6, 2016
Mayflies (the insect order Ephemeroptera) are a fascinating group, which represents the oldest winged insects, estimated to have been existing on the Earth since the lower Carboniferous, or, approximately for 350 million years. They are characterized by exclusively aquatic larvae, a unique fully winged subimaginal stage (the stage right before the young mayfly transforms into a sexually mature adult) and, typically, rather short life as an adult. While identification has generally been considered difficult, and good research collections are to be found in relatively few specialised institutions, three biologists from Turkey and Austria have recently concluded a review of the Turkish mayfly fauna, in which they also add two species newly recorded from the country. They also list 157 mayfly taxa representing 33 genera and 14 families, including 24 species considered endemic to Anatolia. With their annotated overview of the present state of knowledge concerning mayflies in Turkey, the authors aim to facilitate future research. Synthesis of all previous records of mayflies from Turkey together with new records, a map of provinces and pertinent literature, are all included in the latest paper published by scientists Dr Ali Salur, Hitit University, Çorum, Turkey, Dr Mustafa Cemal Darilmaz, Aksaray University, Aksaray, Turkey, and Dr Ernst Bauernfeind, Natural History Museum Vienna, Austria, in the open access ZooKeys. The data in the review are based on a detailed study of literature on Ephemeroptera in Turkey as well as on hitherto unpublished material housed in the Natural History Museum Vienna. Unpublished theses have not been considered. By 2015, there have been well over 70 scientific papers and books published on Ephemeroptera in Turkey from both Turkish and foreign researchers. Distribution of species-group taxa in Turkey have been listed and referenced according to publication dates. National distribution records (without specific data at least on province level) have been listed under 'Turkey'. Type locality of species were only provided if the taxon had originally been based on material from Turkey. Remarks on different taxonomic opinions and nomenclature have been added under 'Comment' whenever appropriate. Websites http://www.faunaturkey.com and http://www.faunaturkey.org (launched in 2013) are meant to contribute more information on research about the fauna of Turkey. The data provided in the present study will also be added to the websites following publication. Explore further: Access to Wikileaks blocked in Turkey as it releases emails More information: Ali Salur et al, An annotated catalogue of the mayfly fauna of Turkey (Insecta, Ephemeroptera), ZooKeys (2016). DOI: 10.3897/zookeys.620.9405