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Öğe Classification of organic and conventional olives using convolutional neural networks(Springer London Ltd, 2021) Unluturk, Mehmet S.; Kucukyasar, Secil; Pazir, FikretThis paper presents a convolutional neural network (CNN) to classify between the conventionally and organically cultivated Memecik varieties of green olives. The image forming method called the rising paper chromatography is utilized in preparing the images of Memecik varieties of green olives for CNN. In the rising chromatography method, 20, 30, and 40% sample concentrations were determined as the suitable concentrations for both organic and conventional olives. The concentrations of AgNO3 and FeSO4 were determined as 0.25, 0.5, 0.75 and 1% for both conventional and organic samples. The visual differences used for differentiation of different types of Memecik green olives are usually determined according to the regional color differences, the vivid color occurrence, the width and the frequency of bowl occurrence, the thin line, and the picks at drop zone by the expert assessors. The testing results in this study verified the effectiveness of the CNN methodology in differentiating between the organically and conventionally cultivated Memecik green olives. The newly designed neural network achieved 100% accuracy. Furthermore, this high accuracy achieved by CNN might suggest that it can be effectively used in place of the expert assessors.Öğe A Comparative Study on Response Surface Optimization of Supercritical Fluid Extraction Parameters to Obtain Portulaca Oleracea Seed Oil with Higher Bioactive Content and Antioxidant Activity Than Solvent Extraction(Wiley, 2023) Zadeh, Janan Hossein; Ozdikicierler, Onur; Pazir, FikretPortulaca oleracea (purslane) seed oil is a rich source of omega-6 and omega-3 fatty acids. Extraction of the purslane seed oil while preserving its high nutritive quality has been a challenge since conventional solvent extraction has many adverse effects on bioactive content. This study aims the optimization of purslane seed oil supercritical fluid extraction (SFE) conditions and to compare purslane seed oils obtained with SFE and conventional solvent extraction in terms of oil yield, along with the purslane seed oil quality and bioactive content. For this purpose, the SFE process parameters (pressure, temperature, static time, and dynamic time) are optimized for oil yield, omega-6, omega-3, and antioxidant activity using response surface methodology (RSM). Optimum SFE pressure, temperature, static time, and dynamic time levels are determined as 350 bar, 50 degrees C, 20 min, and 90 min, respectively. Oil yield and physicochemical quality properties of conventional solvent extract and SFE samples are determined and compared. Consequently, samples obtained via SFE and solvent extraction have similar quality properties. Distinctly, SFE allows an extraction with 5.6% higher total phenolic compound (TPC) and 33% higher antioxidant activity than solvent extraction.Practical Applications: In the study, the extraction of purslane oil using supercritical fluid extraction is optimized with different approaches. At optimum conditions, purslane oil is extracted and all physicochemical properties and the process efficiency (yield) are compared with the solvent-extracted samples. The results of this study make supercritical fluid extraction of purslane seed oil possible since all optimum operating conditions of a pilot-sized extractor are reported in the study. It is believed that the results provide a good starting point for industrial operations. Moreover, researchers also believe that research studies unveiling the new potential oil-bearing seeds are important to overcome the vegetable oil shortage that emerged this year.Öğe Discrimination of bio-crystallogram images using neural networks(Springer, 2014) Unluturk, Sevcan; Unluturk, Mehmet S.; Pazir, Fikret; Kuscu, AlperThis study utilized a unique neural network model for texture image analysis to differentiate the crystallograms from pairs of fresh red pepper fruits from conventional and organic farms. The differences in visually analyzed samples are defined as the distribution of crystals on the circular glass underlay, the thin or thick structure of crystal needles, the angles between branches and side needles, etc. However, the visual description and definition of bio-crystallogram images has major disadvantages. A novel methodology called an image neural network (INN) has been developed to overcome these shortcomings. The 1,488 x 2,240 pixel bio-crystallogram images were acquired in a lab and cropped to 425 x 1,025 pixel images. These depicted either a conventional sweet red pepper or an organic sweet red pepper. A set of 19 images was utilized to train the image neural network. A new set of 4 images was then prepared to test the INN performance. Overall, the INN achieved an average recognition performance of 100 %. This high level of recognition suggests that the INN is a promising method for the discrimination of bio-crystallogram images. In addition, Hinton diagrams were utilized to display the optimality of the INN weights.Öğe Effect of treatments with UV-C light and electrolysed oxidizing water on decontamination and the quality of Gemlik black olives(Springer International Publishing Ag, 2020) Gok, Sila Barut; Pazir, FikretThe efficacy of ultraviolet-C (UV-C), electrolysed oxidizing water (EOW) and sodium hypochlorite (NaOCl) solution was investigated as non-thermal processes for the surface decontamination of olives. Olives were irradiated at different UV-C doses (0-4770 mJ/cm(2)) and washed with EOW and NaOCl solutions at different free chlorine concentrations (15, 30, 50, and 80 mg/L). the maximum reduction in microbial load was obtained at 80 mg/L concentration and 4770 mJ/cm(2) for washing and irradiation treatments, respectively. L* (lightness), a* (redness) and b* (yellowness) values as well as sensorial attributes were not affected by the UV-C treatments. Our results emphasize that UV-C radiation is effective in reducing surface initial microbial load without any sensorial changes for all doses applied. Nevertheless, with increasing UV-doses, the reduction rate increased. All chlorine concentrations of EOW and NaOCl solutions were effective in reducing surface microbial load compared to control. However, in terms of microbial reduction there was no significant difference among chlorine concentrations except for the yeast and mould count.Öğe The effects of spray drying process parameters on the characteristic process indices and rheological powder properties of microencapsulated plant (Gypsophila) extract powder(Elsevier Science Bv, 2014) Ozdikicierler, Onur; Dirim, Safiye Nur; Pazir, FikretGypsophila Saponaria afficinalis, is in the family Caryophyllaceae, native to southern Europe and southwest Asia, and commonly known as the soapworts. The aqueous extract was obtained by sequential extraction of soapwort plant roots and prior to spray drying operation maltodextrin was added as a carrier material to adjust the soluble solid content (degrees Bx) of the soapwort extract (15 degrees Bx, 22.5 degrees Bx, 30 degrees Bx). Powder properties of the product and the characteristic process indices were determined after spray drying of soapwort extracts with different air inlet (110 degrees C, 135 degrees C, 160 degrees C) and outlet temperatures (50 degrees C, 65 degrees C, 80 degrees C) with the other process parameters being constant. The moisture content of the powders changed between 6.35% and 0.44% being mostly affected by increasing outlet temperatures. Productivity and drying rate showed a decreasing tendency as air outlet temperature increased since high outlet temperatures required low feed flow rates. Dissolution time and tapped density were determined as powder characteristics combined with foam producing capacity, color and morphological properties. In general, results showed that spray drying can satisfactorily be used for spray drying of soapwort root extracts with acceptable moisture and water activity of the powders and functional properties of the reconstituted powders. (C) 2013 Elsevier B.V. All rights reserved.Öğe Energy and exergy analyses of spray drying of a fruit puree (cornelian cherry puree)(Inderscience Enterprises Ltd, 2015) Saygi, Gulsefa; Erbay, Zafer; Koca, Nurcan; Pazir, FikretIn this study, a fruit powder was produced from the mixture of cornelian cherry puree (CCP)/maltodextrin by spray drying. The performance of spray drying process and the drying system was evaluated by energy and exergy analyses. Experiments were carried out with an inlet drying air temperature range of 130-160 degrees C, an outlet drying air temperature range of 65-85 degrees C and CCP/maltodextrin ratio was chosen as 60/40, 50/50, and 40/60 (w/w). While the energetic and exergetic efficiencies for the drying process were calculated between 3.2-17.3% and 0.7-4.1%, the exergetic efficiencies of the spray dryer and overall system were found to vary between 27.0-39.1% and 26.7-32.9%, respectively. Results showed that high inlet and low outlet air temperatures caused high effectiveness for drying process. However, maltodextrin concentration of the feed did not have significant effects on the process performance.Öğe Extraction of anthocyanins from grape pomace by using supercritical carbon dioxide(Wiley, 2020) Pazir, Fikret; Kocak, Erinc; Turan, Funda; Ova, GuldenRed grape pomace contains many secondary metabolites including anthocyanins and phenolic acids which significantly contribute to its antioxidant capacity. Herein, anthocyanins were extracted from grape pomace by using supercritical carbon dioxide. Ethyl alcohol was used as cosolvent. the temperature and pressure were kept constant during the extraction (95 degrees C and 100 bar). the total extraction time was 180 min. the total monomeric anthocyanin content (TMAC) and total antioxidant capacity (TAC) were analyzed by taking samples from the extract at the 30th, 60th, 90th, 120th, 150th, and 180th min. the TMAC of grape pomace is 1,932.1 mg/kg dry matter. the TMAC and TAC values at each time intervals were calculated to be 579.2, 406.1, 123.7, 52.8, 38.5, and 16.4 mg/kg dry matter and 177.3, 171.1, 90.6, 44.7, 19.6, and 10.0 mg Trolox/100 g dry matter, respectively. the extractable TMAC and TAC values gradually decreased with time. the cumulative total anthocyanin content and antioxidant capacity increased with time. Practical applications the extraction of bioactive compounds from food matrices by using novel technologies has recently become a major challenge for the food industry since cost effective measures should be adopted in order to maximize the efficiency and to achieve the highest possible quality with the minimum input. Supercritical carbon dioxide (SCCO2) extraction has been recognized as one of such methods and it aims to shorten the process time while inducing the possibly least environmental damage. This research may serve as a guide for the potential industrial applications owing to following reasons; the determination of the steady state during extraction is critical to terminating the extraction at this steady state point to save energy and labor costs. the optimization of the extraction time will surely assist the cost reduction of food colorants including anthocyanins, which are yielded by the SCCO2 extraction and used for the production of jams and muffins.Öğe IMPROVING SWEET CORN x DENT CORN HYBRIDS BASED ON KERNEL COLOR, SIZE AND QUALITY PROPERTIES(Parlar Scientific Publications (P S P), 2019) Altinel, Burak; Tonk, Fatma Aykut; Istipliler, Deniz; Tosun, Muzaffer; Pazir, FikretThe objective of this study was to determine the most-promising F-1 hybrids with respect to kernel color, size and quality properties using sweet corn and dent corn inbred lines as parents. In this study, the F-1 hybrids were produced using four sweet corn inbred lines as female parents (SC1, SC2, SC3 and SC4) and two dent corn inbred lines as male parents (DC1 and DC2). We observed that kernel size properties and 1000-kernel weight values of F-1 hybrids were similar to those of the male parents. The hybridization of SC1 and SC4 with male parents exhibited a significant increase in L*, a*, b* values in their F-1 hybrids. Total sugar contents of the F-1 hybrids were found to be similar to those of sweet corn inbred lines. The highest sucrose content was found in the SC3 and accordingly in the SC3's hybrids. (o)Brix values indicated that our F-1 hybrids are at an adequate level from the standpoint of a sweet taste. The findings in the present study led to the conclusion that it is possible to produce new type sweet corn x dent corn hybrids with improved characteristics.Öğe Inactivation of Penicillium digitatum and Penicillium italicum under In Vitro and In Vivo Conditions by Using UV-C Light(Int Assoc Food Protection, 2013) Gunduz, Gulten Tiryaki; Pazir, FikretIn this study, the effects of UV-C on two of the main wound pathogens of citrus fruits, Penicillium digitatum and Penicillium italicum, were investigated with different inoculation methods in vitro and on oranges. P. digitatum and P. italicum spores were inoculated onto the surface of potato dextrose agar or oranges using spread, spot, wound, and piercing inoculation methods. UV-C treatment for 1 min from a working distance of 8 cm reduced the numbers of P. italicum and P. digitatum by about 3.9 and 5.3 log units, respectively, following spread inoculation under in vitro conditions. Significant reductions were obtained after 1-min UV-C treatments of the tested fungi following inoculation using the spread and spot methods. With inoculation by the wound and piercing methods, the tested spores were not inactivated completely even after 10- and 20-min treatment times, respectively. The application of UV-C (7.92 kJ m(-2)) on oranges reduced the percentage of oranges infected at least threefold compared with the rate of infection in the untreated control samples. UV-C irradiation could effectively inactivate spores of P. italicum and P. digitatum inoculated by the spread plate and spot inoculation methods under in vitro and in vivo conditions. On the other hand, because of the low penetration ability of UV-C light, the tested fungi were not completely inactivated following inoculation with the wound and piercing methods. UV-C treatment has potential for use in surface decontamination of citrus fruits.Öğe Investigation of The Potential Applications of Cold Plasma Technology in Food Safety(2023) Hossein Zadeh, Janan; Pazir, FikretNowadays, the demand for the consumption of healthy foods is increasing day by day. Although fruits, vegetables, and foods made from them come first among these foods, meat and meat products are of great importance. However, there have been reports of food poisoning from such meals. Furthermore, problems are encountered in exports due to the microbial load of many such products. Different chemicals are used to reduce the microbial load of these products. However, due to the residue, these compounds are not utilized in many countries. Therefore, different methods are being investigated, and new technologies are being developed. Hydrostatic pressure, ultrasound, pulsed electric fields, irradiation, and pulsed light are some of these technologies. The purpose of this review is to investigate the possibilities of using the cold plasma system, which is one of these technologies, for the sterilization of foods. In simple terms, cold plasma is the fourth state of matter and is defined as a gaseous composition of ionic gas, polar ions, and gas atoms produced under atmospheric or low-pressure conditions. In addition to the many advantages of cold plasma, it has the possibility of being used for different purposes. Besides surface disinfection and detoxification, it is also used in the sterilization of packaged products, fresh fruits and vegetables, liquid foods, and meat and meat products.Öğe Modeling and optimization of the spray drying parameters for soapwort (Gypsophila Sp.) extract(Korean Society Food Science & Technology-Kosfost, 2019) Ozdikicierler, Onur; Dirim, Nur; Pazir, FikretIn this study, the effects of spray drying parameters as feed soluble solid content, inlet air temperature and outlet air temperature on spray drying of soapwort (Gypsophila arrostii) extract have been examined. Central composite design was used with 15-30 degrees Bx, 110-160 degrees C and 50-80 degrees C for feed soluble solid content, inlet air temperature and outlet air temperature, respectively. Moisture content, water activity, tapped density, total saponin content and foam volume of the obtained powders were measured as responses of the experimental plan. the spray drying parameters were optimized by considering saponin content and foam volume by response surface methodology. According to the numerical optimization, optimum feed soluble solid content, inlet and outlet air temperatures were 15 degrees Bx, 160 degrees C and 67 degrees C respectively with a desirability factor of 0.822. After verification at optimum conditions, the error percentages were found to be 5.96% and 2.15% for saponin content and foam volume respectively.Öğe Oxidative stability of olive oils with supercritical carbon dioxide extracts of olive leaf(Innovhub Ssi-Area Ssog, 2022) Sevim, Didar; Koseoglu, Oya; Pazir, Fikret; Ova, Gulden; Kadiroglu, Pinar; Alper, YukselIn this study, quality parameters and oxidative stability of olive oils added with olive leaf (OL), an agricultural by-product extracted by the supercritical carbon dioxide (SCD) method, were evaluated. The SCD OL extraction method was applied at 100 degrees C, 100 bar and 80 minutes. Extracts containing phenolic substances obtained from olive leaves were added to refined olive oil (ROO) (E) at concentrations of 350 (A), 200 (B), 150 (C) and 60 mg CAE/kg oil (D). Olive oil samples were stored in clear glass bottles for 12 months under light (L) and dark (D) conditions. Samples were analysed at 0, 3, 6, 9 and 12 months of storage period. The results of the analyses revealed that the amount of free fatty acid values (FFAV), peroxide value (POV), total phenolic content (TPC), chlorophyll (TChl) and carotenoid (TCar) content and oxidative stability index (OSI) increased as the olive leaf extract (OLE) addition ratio increased. When the effect of OLE concentration on the amount of a- tocopherol was examined, it was determined that the amount of a- tocopherol was higher in ROO (E) and this amount decreased with the addition of OLE. In the samples which OLE was added, odours like alcohol, henna and dried herbs were detected as a result of sensory analysis. Principal component analyses (PCA) indicated that olive oils were discriminated clearly based on the concentrations of OLEs. As a result, it was determined that the TPC, TChl and TCar content and OSI values were the highest in the A sample, which was stored in the dark and had the highest OLE content. Sample A, which is rich in antioxidant components, can be said to be the best example enriched with OLE, apart from sensory properties. In terms of the content of AT, which is equivalent to vitamin E, we can say that the E sample stored in the dark has the best properties except for the sensory properties.Öğe Process Neural Network Method: Case Study I: Discrimination of Sweet Red Peppers Prepared by Different Methods(Hindawi Publishing Corporation, 2011) Unluturk, Sevcan; Unluturk, Mehmet S.; Pazir, Fikret; Kuscu, AlperThis study utilized a feed-forward neural network model along with computer vision techniques to discriminate sweet red pepper products prepared by different methods such as freezing and pureeing. The differences among the fresh, frozen and pureed samples are investigated by studying their bio-crystallogram images. The dissimilarity in visually analyzed bio-crystallogram images are defined as the distribution of crystals on the circular glass underlay and the thin or the thick structure of crystal needles. However, the visual description and definition of bio-crystallogram images has major disadvantages. A methodology called process neural network (ProcNN) has been studied to overcome these shortcomings.
