Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2024Scopus SJRQ1Design of Ohmic Thawing Cell with Hydrostatic Pressure Units: Application in Minced Beef
Döner, Deniz; Çokgezme, Ömer Faruk; Çevik, Mutlu; İçier, Filiz
The thawing process is a common processing method used in the meat industry. To ensure provide food safety and protect meat quality, the thawing process should be carried out carefully. Ohmic thawing (OT) is one of the novel thawing methods. In this study, a custom-designed ohmic thawing prototype was set up and used to thaw frozen minced beef samples in different shapes (X: 13 × 4 × 3 cm3; Y: 13 × 6 × 2 cm3; Z: 13 cm height × 3.91 cm diameter) at 3 different voltage gradients (10–13-16 V/cm) by using 3 different electrode designs (E1, titanium foil; E2, needle type titanium electrode; E3, titanium embossed). The optimum OT condition resulting in a high-quality product with the highest process efficiency was determined. As an optimization procedure, a three-level general factorial design was performed. Thawing time, drip loss, thawing ratio, maximum temperature, ohmic power consumption, energy efficiency, and exergy efficiency values were used as responses. The cylindrical sample shape resulted in higher changes in quality and decreased performance of the process. The optimum ohmic thawing condition was a 16 V/cm voltage gradient for Y-shaped samples by using an E2 electrode design. The thawing time for the optimum condition was 2074s corresponding ohmic power consumption of 15.84 W. The drip loss during thawing was measured at 1.20%. The maximum temperature reached during the thawing process was recorded as 15.90 °C. Energy efficiency and exergy efficiency values were greater than 35%. Based on these results, the overall desirability of the ohmic thawing method was evaluated as 0.755. The obtained desirability value indicated the ohmic thawing method to be highly efficient and effective in achieving optimal thawing outcomes. The results of this study could give valuable information on the design of industrial-scale ohmic heating units to be used with solid foods, especially for thawing purposes.
AtıfScopus13WoS11
İncele - MakaleAçık Erişim2023Investigation of Pectin Production by Ohmic Heating Assisted Extraction Method Using Different Types of Acids from Lemon Peel Powder
Sabanci, Serdal; Çevik, Mutlu; Goksu, Ali
Depending on the developing technology, people's use of alternative heating methods is increasing. In the present study, a solution of lemon peel powder prepared with 3 different acids (sulphuric, hydrochloric, and nitric acid) was heated from 20 °C to 80 °C at a constant pH of 1.5, solid: liquid ratio (1:40), and a voltage gradient of 10 V/cm. It is aimed to investigate the change of electrical conductivity value and the effect of acid type on pectin yield at the end of 10 minutes of processing time at 80 °C extraction temperature. As a result of the experiments, the heating times of the samples in the ohmic heating-assisted extraction system varied between 199 and 252 s, and the electrical conductivity values varied between 0.89 and 2.10 S/m. In addition, the electrical conductivity value increased in 3 different acid types as the temperature value increased. Also, pectin yield values for 3 different acid types varied between 8.88% and 10.72%, and the highest pectin yield was obtained in the extraction process obtained from the solution prepared with sulfuric acid. It was determined that the use of different acid types had a significant effect on the heating time, electrical conductivity, and pectin yield (p0.05). According to the results, it has been determined that pectin extraction can be done successfully using the ohmic heating-assisted extraction system. It is expected that the data obtained from the use of current heating methods in the extraction of such products will make a serious contribution to the literature.
- MakaleAçık Erişim2022Investigation of the Changes in Rheological Properties of Purple Basil Sherbet Samples Concentrated by Ohmic Heating at Different Voltage Gradient
Çevik, Mutlu; Eroğlu, Zeynep
Purple basil is widely used medicinally and aromatically due to its essential oil properties, and it is a plant that stands out with its antibacterial, antimutagenic and antioxidant properties. It has been determined that purple basil has positive effects on health such as appetizing, insomnia, sputum, diuretical and antispasmodic. Purple basil contains high concentrations of anthocyanins and with these properties it stands out as a potential new source of stable red pigments for the food industry. In recent years, it has been seen that purple basil has been processed into different products such as tea and sherbet in order to benefit from its functional properties. With the processing of purple basil into different products, it is seen that the consumption of basil and basil products has increased by consumers. In this study, purple basil sherbet samples were concentrated at different voltage gradient values (14, 17 and 20 V/cm) under atmospheric conditions with ohmic heating up to 25% soluble solid content (SSC) and the changes in their rheological properties during the concentration process was investigated. The changes in the rheological properties of the purple basil samples were determined in the range of 1-148 s-1 shear rate values and measurement temperature was 25°C. The compatibility of different rheological models (Newton, Power-Law and Herschel-Bulkley) to the experimental data was statistically evaluated to determine the flow behavior index of the purple basil sherbet samples. It has been determined that the shear stress values increased as the shear rate values increased in all the process conditions. Similarly, at the same shear rate values, it was determined that the shear stress values increased as the SSC values increased. It has been determined that the best suitable rheological model was Herschel-Bulkley Model for all purple basil sherbet concentrates. It is thought that the results obtained will provide important data to the food and machinery industry for the installation of pilot and industrial scale ohmic heating systems.
AtıfOpenAlex2
İncele - MakaleYalnız künye2022Scopus SJRQ2Performance evaluation of pectin extraction from grapefruit peel powder by ohmic heating
Goksu, Ali; Duran, Gülseven; Çilingir, Seda; Çevik, Mutlu; Sabanci, Serdal
This study is to investigate the performance properties during the extraction of pectin from grapefruit peel powder using ohmic heating. Pectin extraction was carried out under different voltage gradients (7–11 V/cm), different solid: liquid ratios (1:20–1:60), and different holding times (0–180 min) at constant pH and temperature (80°C). The voltage gradient and solid: liquid ratio affected the time to reach the target temperature. The highest energy efficiency value for all voltage gradients and solid: liquid ratios were obtained in the 0 min holding time, and the efficiency value, which changed between 89.47% and 56.02%, was negatively affected by the increase in the holding time. The exergy efficiency was lower than the energy efficiency and decreased due to the increasing holding time and decreasing voltage gradient. Also, the exergy efficiency was found to be between 73.69% and 18.09%. Determining the performance characteristics of the system will make a significant contribution to pilot and industrial-scale system/process applications for the future. Practical application: In this study, pectin was successfully obtained from grapefruit powder using an ohmic heating system. The operating conditions for the obtained pectin include constant pH (pH:1) and temperature (80°C) but various voltage gradients, solid: liquid ratios, and extraction times. It has been observed that voltage gradient and extraction time were effective on energy efficiency. When looking at exergy efficiency, voltage gradient, solid: liquid ratio, and extraction time were effective. It has been observed that the improvement potential (IP) value calculated for the system decreases depending on the increasing voltage gradient. The results obtained in this study are thought to be an important data source for literature, pilot, and industrial-scale production systems. It has been realized that ohmic heating, which is increasingly used, is an alternative technique for pectin production.
AtıfScopus13WoS12OpenAlex16İncele - MakaleAçık Erişim2021Investigation of the changes in electrical conductivity values and rheological properties of poppy flower syrup
Çevik, Mutlu
In this study, the changes of electrical conductivity values of poppy flower syrups applied ohmic heating at different voltage gradients (30, 35 ve 40 V/cm) were investigated during the heating process. In addition, the changes of the rheological properties of the samples at different temperature values were determined and their suitability to different rheological models were tested. It was determined that the heating times of the samples changed between 280 and 592 s and tended to decrease depending on the increase in the applied voltage gradient. It was detected that the best model describing the rheological behavior of samples at all temperature values was the Power -Law Model. It was determined that the consistency coefficient (K) and apparent viscosity (μₐₚₚₐᵣₑₙₜ) values decreased as the temperature values increased. It was determined that the samples showed non- Newtonian dilatant (shear thickening) flow behavior under all measurement process conditions.
AtıfOpenAlex2TR Dizin1İncele - MakaleYalnız künye2021Determination of Rheological Properties of Gezo Pekmezi (Molasses)
Çevik, Mutlu
In this study, the changes in the rheological properties of Gezo pekmez (molasses) samples at different temperature values and their suitability for different rheoleogic models were investigated. In addition, changes in viscoelastic properties of pekmez (molasses) samples at different frequency values were determined. It was determined that the best model describing the rheological behavior of molasses samples at all temperature values was the Power-Law Model. It was detected that K and n values decreased as the temperature values increased. Since phase angle values were greater than 1, it was determined that the fluidity character was more dominant than elasticity character. In other words, molasses samples were found to have viscoelastic properties. It is thought that the result of present study fulfill the lack of information on determining the changes in the rheological properties of the molasses samples.
AtıfOpenAlex2TR Dizin1İncele - MakaleAçık Erişim2021Scopus SJRQ1Influences of sample shape, voltage gradient, and electrode surface form on the exergoeconomic performance characteristics of ohmic thawing of frozen minced beef
Çokgezme, Ömer Faruk; Döner, Deniz; Çevik, Mutlu; Kemahlıoğlu, Ali Varsın; İçier, Filiz
In the present study, it was aimed to investigate the exergoeconomic performance of ohmic thawing (OT) system during the thawing of frozen minced meat (lean beef). The effects of the sample shape (X: 13 × 4 × 3 cm, Y: 13 × 6 × 2 cm, Z: cylinder with a height of 13 cm and diameter of 3.91 cm), electrode surface form (titanium foil with smooth surface, titanium electrode with needle-type surface and titanium electrode with pyramid-type surface), and voltage gradients (10, 13, and 16 V/cm) were investigated. Lower exergoeconomic values were obtained for the cylindrical shape compared to the rectangular prism. The lowest exergy efficiency value (12.45 ± 0.42), is was obtained for the cylindrical shape at 10 V/cm voltage gradient with titanium foil electrode. The needle-type surface electrodes had higher performance values than other electrodes. The exergoeconomic performance increased as the voltage gradient increased. The lowest unit exergy cost (72.40 ± 2.8) was obtained for rectangular prism shape at 16 V/cm with needle-type electrode. The comprehensive exergoeconomic evaluation in this study exhibited the energy utilization effectiveness and unit exergy cost of OT.
AtıfScopus32WoS28OpenAlex30İncele - MakaleYalnız künye2021Scopus SJRQ2Investigation of time effect on pectin production from citrus wastes with ohmic heating assisted extraction process
Sabanci, Serdal; Çevik, Mutlu; Göksu, Ali
Pectin is usually extracted by exposure to a high temperature and a specific pH value by conventional methods. However, due to reasons such as low energy efficiency of the process and damage to the pectin, alternative thermal and non-thermal methods are used in the pectin extraction process. In this study, the effect of different processing times (0, 5, 15, 30, 60, 120, 180 min) on pectin extraction was investigated for grapefruit, lemon, and orange samples at 80°C. Besides, it was determined that the electrical conductivity value ranged between 1.46–2.06 S/m during heating, the electrical conductivity value of the pH solution adjusted with sulfuric acid. Accordingly, it was figured out that the total amount of energy consumed increases as the process holding time increases. However, it was determined that there was a decrease in the average power value by turning on–off the system. Practical Application: Pectin is one of the additives used in many areas in the food industry. Pectin is now produced especially from agricultural waste peel. During this production, it is subjected to long processes at certain pH and certain temperatures. With the present study, determination of pectin yield over a wide period of time by using ohmic heating process and total ohmic heating energy was determined. In this way, it is thought that a serious contribution will be made to the literature and industry regarding different industrial agricultural waste peel (orange, grapefruit, lemon) during pectin production.
AtıfScopus36WoS31OpenAlex36İncele - MakaleAçık Erişim2020Ohmik destekli vakum altında evaporasyon sistemi ilekonsantre edilen nar suyunun reolojik özelliklerindekideğişimin incelenmesi
Icier, Filiz; Çokgezme, Ömer Faruk; Sabanci, Serdal; Çevik, Mutlu
Bu çalışmada, nar suyunun ohmik destekli vakum altında evaporasyon (OAVE) yöntemi ile farklı voltaj gradyanları (7.5, 10 ve 12.5 V/cm) uygulanarak %40 suda çözünür kuru madde (SÇKM) içeriğine kadar konsantre edilmesi sırasında reolojik özelliklerindeki değişim incelenmiş ve vakum altında evaporasyon (VAE) yöntemi ile karşılaştırılmıştır. Evaporasyon işlemi sırasında incelenen tüm SÇKM içeriklerinde nar suyu konsantrelerinin reolojik davranışını en iyi ifade eden modelin Üssel Model olduğu tespit edilmiştir. Bu model ile öngörülen görünür viskozite (µgörünür) ve akış davranış indeksleri (n) değerlerinin SÇKM içeriği arttıkça artma eğilimi gösterdiği belirlenmiştir. Yüksek voltaj gradyanlarında (10 ve 12.5 V/cm) uygulanan OAVE işlemi ile yüksek kıvam katsayısına sahip nar suyu konsantrelerinin elde edilebileceği tespit edilmiştir. Ek olarak, VAE işlemine benzer karakterde kıvama sahip konsantre eldesi için ise düşük voltaj gradyanında uygulanan OAVE işleminin alternatif olarak uygulanabilir olacağı sonucuna ulaşılmıştır.
AtıfOpenAlex3TR Dizin2İncele - MakaleAçık Erişim2020Scopus SJRQ1Thermal Image Processing Technique for Determination of Temperature Distributions of Minced Beef Thawed by Ohmic and Conventional Methods
Döner, Deniz; Çokgezme, Ömer Faruk; Çevik, Mutlu; Engin, Mustafa; İçier, Filiz
In the present study, the effectiveness of ohmic thawing (OT) on temperature distribution (TD) was evaluated by using a non-destructive measurement method: thermal imaging (TI). The effects of both OT process parameters and sample properties on TD of thawed minced beef were determined. Thermal images were taken from the central cross-sectional area of a thawed sample. In the first part of the study, the effects of OT system parameters (voltage gradient; 10–13–16 V/cm and electrode type; E1:titanium foil electrode with a smooth surface, E2: needled-type titanium electrode, E3: titanium electrode with pyramid surface shaped) and sample shape (X: 13 × 4 × 3 cm3; Y: 13 × 6 × 2 cm3; Z: 13 cm height × 3.91 cm diameter) were analyzed in detail. The best thawing condition (electrode type E2 and sample shape Y) was determined by taking into account of thawing time and TD properties obtained from a developed TI processing technique. In the second part of the study, the effects of OT process on TD properties of minced beef having different fat contents (2–10–18%) were compared with those of two different conventional thawing processes (stationary cold ambient + 4 °C -RT and under cold running water + 4 °C -WT). The percentage of thawed portions in central section was above 68% for OT and varied between 12 and 54% for CT. Rectangular-shaped samples had more homogeneous temperature distributions than cylindrical samples (p < 0.05). TI could be used to control the process by non-destructive monitoring of temperature during OT.
AtıfScopus36WoS31OpenAlex35İncele