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Öğe Analysis and Optimization of the Effect of Process Parameters of Silver Anode Technique on Pseudomonas aeruginosa in Raw Milk(Instituto de Tecnologia do Parana, 2023) Cibik, Sergül; Duran, AyhanThe present research aimed to experimentally and statistically investigate the effects of current and time parameters on the inhibition of Pseudomonas aeruginosa ATCC 27853 using the silver anode technique. Accordingly, cold raw milk was divided into groups and the experimental design was carried out according to the Taguchi L16 index. Four levels of current intensity (5, 10, 15, and 20 ?A) and duration (15, 30, 45, and 60 sec) were selected as the process parameters, and the bacterial colony count was chosen as the output parameter. The bacteria were inoculated into raw milk, stored in the cold and the silver anode technique was applied. After incubation Pseudomonas aeruginosa bacterial colony counts were determined. Experimentally-obtained bacterial colony counts were statistically analyzed using the Taguchi method, ANOVA, and regression analysis. The optimum process parameters for the lowest bacterial colony count (Nc) were 20 ?A current and 60-second duration. Also according to the variance analysis results, the current intensity was the most effective process parameter on the bacterial colony counts. The regression model developed to estimate the output parameter (bacterial colony counts) yielded successful results with a high determination coefficient (R2) of 96.26%.Öğe Biochemical changes and sensory assessment on tissues of carp (Cyprinus carpio, Linnaeus 1758) during sale conditions(SPRINGER, 2009) Duran, Ayhan; Talas, Zeliha SelamoğluIn this study, some biochemical changes of carp (Cyprinus carpio, Linnaeus 1758) tissues were investigated. Studies have been carried out on carp which have regional economical importance. Storage temperature and time are the most important factors that affect the quality of fish during sales. It was observed that the temperature varied between 9 and 12A degrees C in sale conditions. In addition, we assumed the arrival time of the fish at the fish market to be 0 (zero) h. Biochemical analyses [malondialdehyde (MDA) levels and catalase activity] of carp tissues (muscle, liver, heart, spleen, brain) were carried out on fish which were held for 24 and 48 h, as well as on fresh fish (0 h). In addition, sensory analysis was conducted by a panel consisting of experienced judges of sensory evaluation. Statistically significant (P < 0.05) increases in MDA levels were found in liver, muscle, brain and spleen tissues when comparing the 0- and 24-h groups. But there was no statistically significant (P > 0.05) increase in MDA level in heart tissue of carp after 24 h. There was a statistically significant (P < 0.05) increase in MDA levels in muscle, spleen and heart tissues when comparing the 24- and 48-h groups. In the group examined at 24 h, it was observed that there were statistically significant differences from the 0 h group values (P < 0.05) for catalase (CAT) activity in muscle, brain, spleen and heart tissues. The decreases in CAT activity in liver and spleen tissues were found to be statistically significant (P < 0.05) between the group examined at 24 h compared with the group examined at 48 h. Carp maintained good quality during the selling conditions up to 24 h. This experiment deals with the effects of post-slaughter time and storage temperature on carp tissues. It is concluded that by considering the storage temperature (9-12A degrees C) and storage time (post-slaughter) the product maintained acceptable quality up to 24 h. There was significant deterioration of sensory quality, as a result of changes in chemical constituents.Öğe Correction to: Micro-encapsulation exhibits better protection than nano-encapsulation on phenolics before and after in vitro digestion (Journal of Food Measurement and Characterization, (2024), 18, 12, (9890-9905), 10.1007/s11694-024-02927-7)(Springer, 2025) Şensu, Eda; Altuntaş, Ümit; Gültekin Özgüven, Mine; Duran, Ayhan; Özçelik, Beraat; Yücetepe, AysunThe original version of this article unfortunately contained error in co-author’s afliation. The afliation of author Ümit Altuntaş were incorrectly given as Department of Food Engineering, Faculty of Chemical and Metallurgical Engineering, Istanbul Technical University, Maslak, Istanbul TR-34469, Turkey but should have been Department of Food Engineering, Gümüşhane University, Gümüşhane, Turkey. The original article has been corrected. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional afliations.Öğe Determination of parasitic contamination at production phase in deep-redground pepper (isot) produced in Şanlıurfa, Turkey(2014) Gökçen, Ahmet; Ardıç, Mustafa; Adanır, Ramazan; Duran, Ayhan; Hulusidinçoglu, ZahmetDeep-red ground pepper (Isot), a variety of red ground pepper is a special spices belonging to Sanliurfa and consumed both in Sanliurfa and other provinces of Turkey. The aim of this study was to determine the parasitic contamination levels of deep-red ground pepper produced at home. For this purpose, 82 samples of homemade Isotin Sanliurfa (Turkey) were collected from manufacturers. The occurrence of parasite eggs and protozoon oocysts in the samples was investigated by microscopic examination. Protozoon oocyst and helminth eggs were detected in four of the 82 Isot samples (4.87%). Three of these samples were identified as protozoan oocysts (3.68%) and one of these samples was identified as helminth eggs (1.21%) More hygienic measures should be taken on in order to prevent parasitic contaminations. © Medwell Journals, 2014.Öğe Effects of propolis on biochemical and microbiological parameters in carp (Cyprinus carpio) fillets exposed to arsenic(Iranian Fisheries Research Organization, 2015) Talas Selamoğlu, Zeliha; Duran, Ayhan; Gülhan, Mehmet Fuat; Erdemli, Mehmet ErmanThe purpose of this study was to investigate the therapeutic effects of propolis on biochemical and microbiological parameters in muscle tissues of carp (Cyprinus carpio, Linnaeus 1758) exposed to arsenic. A sublethal concentration of arsenic (0.01 ppm) and/or 0.01 ppm propolis were administered to fish for seven days. Biochemical parameters [pH, lactic acid, total volatile basic nitrogen (TVB-N), and malondialdehyde (MDA) values] and microbiological changes (mesophilic and psychrophilic bacteria count) were determined in fillet of carp in control, arsenic only, propolis only and arsenic+propolis treatment groups. Results showed that the levels of MDA, lactic acid and TVB-N increased (p<0.05) while there were decreases total counts of psychrophilic, mesophilic bacteria and level of pH in arsenic group compared to the control group. Additionally, levels of pH, lactic acid, TVB-N, counts of psychrophilic and mesophilic bacteria in arsenic (0.01 ppm)+propolis (10 ppm) group significantly reduced compared to arsenic group (p<0.05). In conclusion, propolis can affects some biochemical and microbiologic functions and quality in the fillet of carp exposed to arsenic.Öğe Effects of Propolis on microbiologic and biochemical parameters of Rainbow trout (Oncorhynchus mykiss) after exposure to the pesticide(2012) Gülhan, Mehmet Fuat; Duran, Ayhan; Selamoğlu Talas, Zeliha; Kakoolaki, S.; Mansouri, S. M.Cypermethrin is a potential toxic pollutant that directly threatens the aquatic ecosystems and environment. Propolis, a natural product collected from plants by honey bees has many functions, such as antimicrobial, antioxidant, and anti-inflammatory. This study attempted to detrmine some biochemical and microbiological parameters of rainbow trout fillets after exposure to propolis and cypermethrin. The results of the current study revealed that levels of malondialdehyde (MDA), lactic acid, total volatile base-nitrogen (TVB-N), total counts of psychrophilic, and mesophilic bacteria increased in cypermethrin groups (P<0.05), compared to control group. Furthermore, there were no significant differences in pH levels between groups. Additionally, levels of MDA, lactic acid, TVB-N, count of psychrophilic, and mesophilic bacteria in cypermethrin+propolis treated groups were significantly reduce in comparison to exposed groups with cypermethrin (P<0.05). The findings also showed that the fillet quality some biochemical and microbiologic functions of fishes could be changed in groups that exposed to cypermethrin by propolis.Öğe Effects of slaughter methods on physical, biochemical and microbiological quality of rainbow trout Oncorhynchus mykiss and mirror carp Cyprinus carpio filleted in pre-, in- or post-rigor periods(Springer Tokyo, 2008) Duran, Ayhan; Erdemli, Ümit; Karakaya, Mustafa; Yılmaz, Mustafa T.Rainbow trout Oncorhynchus mykiss and mirror carp Cyprinus carpio were slaughtered by either percussion or asphyxiation. For determination of the physical (texture value) and biochemical quality attributes [pH, lactic acid, total volatile basic nitrogen (TVB-N), and malondialdehyde (MDA) values] of trout and carp, the fish were filleted immediately (within 2 h), 12 h after harvest (pre-rigor), 24 and 36 h after harvest (in-rigor), and finally 48 and 60 h after harvest (post-rigor). For microbiological quality attribute (mesophilic and psychrophilic bacteria count) analyses, the fish were filleted immediately (within 2 h) after harvest (pre-rigor), 24 h after harvest (in-rigor) and 48 and 72 h after harvest (post-rigor). By percussion slaughtering followed by pre-rigor filleting, it was possible to process rainbow trout and mirror carp without inflicting excessive handling stress. Percussion slaughter delayed onset of rigor and the percussion-slaughtered fish exhibited a long pre-rigor period (similar to 24 h), giving plenty time for pre-rigor processing. Percussion slaughtering and pre-rigor filleting of fish was considered to be superior to the traditional asphyxiation slaughtering with respect to texture, TVB-N and MDA attributes.Öğe Effects on mortality of biochemical and limnological properties on some fish species in Sultansuyu Dam Lake (Malatya), Turkey(Central Fisheries Research Institute, 2010) Kandemir, Şevket; Örün, İbrahim; Talas, Zeliha; Örün, Gül Nihal; Erdoğan, Kenan; Işık, Mustafa; Altaş, Levent; Duran, AyhanIn this study, hematological and biochemical investigations were carried out on Cyprinus carpio, Leuciscus cephalus, Capoeta trutta ve Capoeta capoeta umbla fish species living in Sultansuyu Dam Lake (Malatya). The physical, chemical and microbiological features of the reservoir were specified and heavy metal analyses were also conducted. As a result of hematological investigation, a statistical increase of P<0.05 in total leukocyte count, and a decrease of P<0.05 in erytrocyte, hemoglobin and hematocrit values were observed. With respect to microbiological analysis, the presence of Enterococcus shows the drainage of domestic wastes into the reservoir. With water analyses, it was found out that the water quality was second rate and the sulphur content in the water was above standard levels. The existence of large amount of sulphur was presumed to be the result of apricot processing. Significant heavy metal pollution was not observed.Öğe Evaluation of the effect of chitosan coating on microbiological and oxidative properties of refrigerated beef(Gıda Teknolojisi Derneği, 2020) Kahve, Halil İbrahim; Duran, AyhanBeef is an animal food sensitive to deterioration with short shelf-life due to its rich nutrient content. Many studies concerned with the use of edible coating are carried out to increase the shelf life of beef. In this study, it was aimed to extend the shelf life of beef using chitosan. For this purpose, the bovine meat was coated with chitosan and stored at +4 ºC for 7 days. Total mesophilic aerobic bacteria, Stapylococcus aureus, Pseudomonas spp. counts and thiobarbituric acid values were analyzed. As a result, it was found that the chitosan coating reduced the TMAB, Pseudomonas spp. counts and TBARS values (P<0.05) and inhibited all S. aureus up to day 5 of storage. According to the data obtained from this study, it has been concluded that chitosan can be used as a bio-preservative in the meat industry due to the antimicrobial and antioxidantive properties.Öğe Investigation of changes in some bioactive propertİes of phenolİc extracts from pulp and seed tissues of zİziphus jujuba during in vıtro digestion(Gıda Teknolojisi Derneği, 2023) Şensu, Eda; Duran, Ayhan; Özçelik, Beraat; Yücetepe, AysunIn this study, changes in angiotensin-I converting enzyme (ACE) inhibitory, ?-amylase inhibitory and antioxidant activities, total phenolic content (TPC), total monomeric anthocyanin content (TMAC) of ultrasonic phenolic extracts from pulp and seed of Ziziphus jujuba were investigated during in vitro digestion. Bioaccessible fractions of phenolics in seed and pulp extracts were calculated as 23.24±4.46% and 9.43±0.24%, respectively. Moreover, bioaccessibility for TMAC in seed extracts (147.83±9.20%) was higher than pulp (15.76±3.89%) (P<0.05). A decrease in the antioxidant activity of the extracts occurred after in vitro digestion (P<0.05). The ACE inhibitory activity of undigested extracts from seed (86.04±0.00%) was higher than that of the undigested pulp extract (42.74±8.57%) (P<0.05). The ?-amylase inhibitory activity of seed and pulp extracts was determined as 49.18±0.35% and 36.07±5.83%, respectively. The results of the study showed that ACE inhibitory activity and ?-amylase inhibitory activity of the polyphenolics from pulp increased after in vitro digestion.Öğe Micro-encapsulation exhibits better protection than nano-encapsulation on phenolics before and after in vitro digestion(Springer, 2024) Şensu, Eda; Altuntaş, Ümit; Gültekin Özgüven, Mine; Duran, Ayhan; Özçelik, Beraat; Yücetepe, AysunIn this study, micro-capsules (by complex coacervation) and nano-capsules (by liposomal encapsulation) containing phenolic extracts from jujube peel (PEJP) were compared in terms of changes in encapsulation efficiency, phenolic and anthocyanin content and antioxidant, angiotensin converting-I enzyme (ACE) inhibitory and ?-amylase inhibitory activities before and after in vitro digestion. According to the results, micro-capsules were prepared with a biopolymer ratio of 0.125:1:1 (PEJP: WPI: GA) at pH 3.4, while nano-capsules were obtained using 1% lecithin and 0.4% chitosan at pH 3.4. Nano-capsules had higher encapsulation efficiency (74.27%) than micro-capsules (67.34%). In contrast, total phenolic content of PEJP was preserved better in micro-capsules before and after in vitro digestion compared with nano-capsules. The highest total monomeric anthocyanin content remained in the undigested micro-capsules and in the digested nano-capsules. Micro-capsules exhibited a stronger antioxidant activity than those of nano-capsules with PEJP with both DPPH and CUPRAC assays. After in vitro intestinal digestion, micro-capsules with PEJP exhibited the highest ACE inhibitory activity (80.00 ± 2.50%) and ?-amylase inhibitory (48.31 ± 0.84%) activity. Considering all these results, micro-capsules protected phenolics better than nano-capsules. The stability of phenolics based foods can be protected by microencapsulation. Also, microencapsulants including phenolics can be added to cosmetic and food supplements.Öğe Optimising Technological Treatments with the Taguchi Approach to Reduce Acrylamide and Improve Colour Properties in Potato Chips(Springer Science and Business Media B.V., 2024) Koyuncu, Dilek; Duran, AyhanToday, consumer demand for food safety, especially in fried foods, is increasing. In the first place, it is demanded to reduce the amount of food toxins, in particular toxins resulting from the thermal process such as acrylamide. This study aimed to examine the effect of different technological treatments on the optimisation of minimum acrylamide and maximum colour properties by applying the Taguchi approach in the production of chips. In this study, design of experiments, signal-to-noise (S/N) ratio, analysis of variance, and regression analysis methods were used to optimise the minimum acrylamide and redness (a*), maximum brightness (L*), and yellowness (b*) values. The optimal parameters for acrylamide were found to be 90 °C slice washing temperature, 175 °C frying temperature, and 175 s frying time. The optimal parameters for colour analysis were determined as 30 °C slice washing temperature, 175 °C frying temperature, and 175 s frying time. Analysis of variance showed that frying temperature and time had a significant (p < 0.05) effect on the results. It was determined that a decrease in frying temperature and time led to a decrease in the amount of acrylamide and redness and an increase in brightness and yellowness. According to the results of the analysis of variance, the most effective technological treatments were frying temperature with effect rates of 37.45% and 60.26% for acrylamide and L* values, respectively, and frying time with effect rates of 40.50% and 44.19% for a* and b* values, respectively. As a result of the study, through the Taguchi method, while quality features in chips were preserved, the amount of acrylamide was reduced.Öğe Optimization of Process Parameters Affecting Glycoalkaloids in Potato Chips Using the Taguchi Method(Springer Science and Business Media B.V., 2024) Koyuncu, Dilek; Duran, AyhanThis study presents the experimental and statistical examination of different process applications in the production process of the glycoalkaloid level in potato chips to which consumers are exposed. In the first stage, slice washing temperature (swt), frying temperature (ftemp) and frying time (ft) were determined as factors that could affect the glycoalkaloid level. Considering industrial applications, three different slice washing temperatures (25, 55 and 85 °C), frying temperatures (180, 185 and 190 °C) and frying times (165, 185 and 205 s) were evaluated for the study. The L9 orthogonal array of the Taguchi method, which has been successfully applied in the analysis of multiple parameters, was used as the experimental design. Examining the S/N (signal/noise) ratios, the optimum process parameters for minimum content of ?-solanine (As) were obtained as 25 °C swt, 190 °C ftemp and 165 s ft. The optimum process parameters were determined for minimum content of ?-chaconine (Ac) as 55 °C swt, 190 °C ftemp and 165 s ft. In the analysis results, as swt decreased, ftemp increased, and ft was shortened; the glycoalkaloid ratio in the chips decreased. Analysis of variance results showed the most effective process parameter was the frying time for ?-solanine and ?-chaconine with 68.2% and 76.5%, respectively. Then comes ftemp with an effectiveness rate of 17.35% and 16.77%. In addition, the regression model developed to estimate the output parameters (As and Ac) yielded successful results with high determination coefficients (R 2) of 90.6% and 92.5%.Öğe The antibacterial effect of silver anode treatment on raw milk(Elsevier Ltd, 2022) Cibik, Sergül; Duran, AyhanSilver has been used as an indirect antibacterial method by the food sector. In this study, the antibacterial effect of silver on raw milk was examined using the silver anode method. The samples were divided into two groups comprising silver-containing and non-silver-containing samples. Then, the two groups were stored at 5 °C, 10 °C, and 25 °C. The changes in the bacterial flora of the raw milk samples were observed at hours 0, 12, 24, and 36. The antibacterial effect of the silver anode treatment on both groups was observed after 12 h. The antibacterial effect increased with increasing storage time. The decreases in the Pseudomonas spp., coliform bacteria, and lactic acid bacteria counts of the silver-containing group were significantly different than those of the control group after 36 h (p < 0.05). The decreases in the Pseudomonas spp. and coliform bacteria counts were greater than the decrease in the lactic acid bacteria count. The Pseudomonas spp. count decreased during the storage period depending on temperature while the growth rates of coliform and lactic acid bacteria decreased with decreasing storage temperature in the silver anode-treated group. The strongest antibacterial effect was observed at 25 °C for Pseudomonas spp. and at 5 °C for coliform and lactic acid bacteria. The results of the study revealed that the silver anode method had a strong antibacterial effect on Pseudomonas spp. and coliform bacteria and a poor antibacterial effect on lactic acid bacteria. Silver ion release into the milk samples was consistently below the legal limits at all storage temperatures.Öğe The effect of bovine lactoferrın on the microbiological properties of raw milk(Gıda Teknolojisi Derneği, 2021) Duran, AyhanMilk is a foodstuff that is very open to contamination depending on the way it is obtained. Also, it is a microbiologically perishable product in terms of the nutritional components it contains. Regarding both regulations and consumer awareness, it cannot be intervened substantially until the process of raw milk in the dairy farms. Therefore, due to the proliferation of Coliforms, especially Pseudomonas spp. and lactic acid bacteria, various problems may arise in both product and technology. The present study aimed to investigate the effect of lactoferrin, a natural inhibitor, on the microbiological properties of raw milk kept in the cold chain. As a result of the study, no inhibitory effect of lactoferrin on lactic acid bacteria was observed. However, it showed a significant antibacterial effect by inhibiting the growth of Pseudomonas spp. and Coliform (P<0.05). As the lactoferrin concentration increased, the antimicrobial effect increased significantly. This showed that lactoferrin can be used as a natural antimicrobial agent in cold systems of liquid foods.Öğe The effect of chitosan coating and vacuum packaging on the microbiological and chemical properties of beef(Elsevier Ltd, 2020) Duran, Ayhan; Kahve, Halil İbrahimBeef is an animal food sensitive to deterioration due to its rich nutrient content. Therefore, some preservation techniques are applied. These include vacuum packaging, a modified atmosphere, a controlled atmosphere and an edible film coating. In this study, it was aimed to extend the shelf life of beef using vacuum packaging (VP) and chitosan coating with vacuum packaging (CC + VP). For this purpose, total mesophilic aerobic bacteria (TMAB), Stapylococcus aureus, lactic acid bacteria (LAB) counts, thiobarbituric acid (TBA) values and total volatile basic nitrogen (TVB-N) content were analyzed in beef obtained from local markets. As a result, it was found that the chitosan coating reduced the TMAB, LAB and TVB-N values and inhibited all S. aureus up to day 15 of storage. In addition, it was seen that the application of CC + VP was significantly more effective (p?0.05) on the reduction of the TBA value, compared to the VP application over a long period of storage (45 days). The combined use of the two technologies is more effective on TVB-N. According to the data obtained from this study, because of the antimicrobial and antioxidant properties of chitosan, it has been concluded that it can be used as a bio-preservative in the meat industry.Öğe The effects of slaughtering methods on physical and biochemical changes in fish(Sila Science, 2012) Talas, Zeliha Selamoğlu; Duran, AyhanWe investigated the effects of two different slaughter methods (sudden death and struggle death) on catalase (CAT) activity and malonedialdehyde (MDA) levels in tissues of rainbow trout (Oncorhynchus mykiss Walbaum, 1792). We analyzed a group of fish without waiting and other fish groups after being kept in 8-10°C for 12, 24, 36 hours. Additionally, sensory analyses were studied by a sensory panel consisting of experienced judges to sensory evaluation. We have been observed significant increases (p < 0.05) in MDA levels and decreases (p < 0.05) in CAT activity of two groups (sudden and struggle death). Using sudden death (unstressed) method, rainbow trout groups showed good quality until to 36th hour, and sensory analyses of struggle death treated groups (stressed) exhibited good quality up to 24th hour. Consequently, we got importance of storage temperature, time and different slaughter methods on biochemical parameters and sensory analyses of some rainbow trout tissues.Öğe Thin layer drying characteristics of eriste: A dried cereal product of Turkey(Berkeley Electronic Press, 2008) Duran, Ayhan; Hayaloğlu, Ali Adnan; Karabulut, İhsanEffect of air temperature (50, 60 and 70 degrees C) and sample thickness (1.0, 1.4 and 1.8 mm) on the thin-layer drying characteristics of eriste was studied by using a tray dryer. The data of sample weight, dry and wet-bulb temperatures were recorded continuously during each experiment and drying curves were obtained. The drying curves were then fitted to five mathematical models available in the literature to estimate a suitable model for drying of eriste. Verma et al. model gave better predictions than other models and satisfactorily described the thin layer characteristics of eriste. The effective diffusivity varied from 1.8 x exp-10 to 1.5 x exp-9 m2 s-1 over the temperature range.
