Browsing by Author "Gül O."

Now showing 1 - 7 of 7

Agglomerated mushroom (Agaricus bisporus) powder: Optimization of top spray fluidized bed agglomeration conditions
(2021-06-01) Atalar İ.; Kurt A.; Saricaoğlu F.T.; Gül O.; Gençcelep H.
Agglomeration process improves instant properties of powders and increases consumer appreciation, reduces losses during production, and facilitates the processability of these powders in the industry. Mushroom powders (MP) have been subjected to agglomeration process at different process parameters: inlet air temperature (50–80°C), atomizing pressure (0.5–1.5 bars), and sprayed pure water amount (20–50 g) and the effects of process parameters on the physical and morphological properties of MP were investigated. The inlet air temperature and pure water amount have a linear effect on moisture content, apparent density, particle size, and porosity. Emulsion stability index was affected by inlet air temperature and atomization pressure. The optimal process condition (70°C inlet temperature 0.5 bar atomizing pressure and 50 g pure water amount) was determined for minimization of moisture content, wetting time, as well as maximation of particle size, porosity, emulsifying and foaming properties, and solubility. The results suggested that improving instant and physical properties make easier the processability of these powders in the industry and increased emulsifying properties show a good opportunity for usage of agglomerated MP in the emulsion systems. Practical Applications: This study showed the effects of the agglomeration process on the physicochemical, morphological, instant, and emulsifying properties of mushroom powders. The improvement of these properties makes it possible to increase the application areas of mushroom powders as a food additive in different food formulas and emulsified products.
Effect of cold-pressed hazelnut cake incorporation on the quality characteristic of meat emulsion system and its potential application for frankfurter-type beef sausages
(2023-01-01) Atalar İ.; Gül O.; Kurt A.; Saricaoğlu F.T.; Gençcelep H.
This research was performed to investigate the effect of hazelnut cake (HC) as a cold press waste product on the physicochemical and textural properties of the frankfurter-type sausages during cold storage. According to the highest emulsion capacity (174.14 mL oil/g), emulsion stability (79.86%), and optimum rheological results obtained in emulsions, 1% HC concentration was selected for the utilization in the sausage formulation. HC added sausage was compared with the control sample at 4°C for 60 days of storage. HC addition increased the hardness and chewiness properties and decreased weight loss of sausages during storage. The incorporation of HC in formulation slowed down the increase in malondialdehyde and conjugated dienes concentrations after the 15th day of storage compared to the control sausages. The results demonstrated that HC presented a good opportunity for protecting the quality parameters of emulsified meat products during storage.
Effect of oleaster (Elaeagnus angustifolia L.) flour addition combined with high-pressure homogenization on the acidification kinetics, physicochemical, functional, and rheological properties of kefir
(2023-01-01) Gül L.B.; Bekbay S.; Akgün A.; Gül O.
Evaluating of Microwave Drying for Hawthorn Slice as Alternative to Convective Drying
(2022-01-01) Beşir A.; Gökmen S.; Gül L.B.; Yazıcı F.; Gül O.
This study aimed to investigate the influence of microwave drying with different power levels as alternative to convective drying method on drying kinetics and main quality attributes of hawthorn slice. At increasing microwave power values, higher drying rate and shorter drying time was observed. The page model was found to give best fit (R2> 0.9961, RMSE< 0.028 and χ2< 0.675x10-3) for all drying treatments. Although the minimum change of color and texture value were obtained at microwave power of 600 W, the convective drying caused less total color and texture change depending fresh sample. Drying process at microwave powers of 600 W and 360 W showed the best quality in terms of rehydration and bioactive properties, respectively. The findings in current work demonstrated that microwave drying at 360 W microwave power might be suitable for drying of hawthorn slices with high quality and bioactive properties as well as low operating costs.
Optimization of Protective Agents for Freeze-Drying of Weisella cibaria N9 as a Potential Starter Culture
(2021-01-01) Gül L.B.; Gül O.; Dertli E.; Çon A.H.
In this study, it was aimed to determine the optimum cryoprotectant formulation for the lyophilization of Weissella cibaria N9 strain isolated from sourdough as a potential starter culture, the characterization of lyophilized culture and its storage stability. The optimum formulation of skim milk, lactose and sucrose as protective agents was determined by the Box-Behnken experimental design based on viability after lyophilization. The optimal cryoprotectant formulation was identified as 5.65% skim milk, 20% lactose and 20% sucrose for maximum cell survival (>99%). Lyophilized culture obtained by the optimum cryoprotectant formulation had acceptable physicochemical properties in terms of moisture and aw, glass transition, particle surface properties and crystal structure. The highest viability was observed at 4̊C (9.11 log cfu/g) with an inactivation rate of 3.37x10-3 day-1. The fastest cell reduction was observed at 70̊C as the result of an accelerated shelf life storage test, and protective agent effectively decreased thermal death. The culture produced by using cryoprotectant could be stored at room temperature for 18 months. Consequently, this protective agent formulation was an effective in protecting W. cibaria N9 viability during lyophilization and storage while lyophilized culture had ideal properties for powder materials, and accelerated shelf life storage test was a useful technique with certain predictability.
Potential of three different lactic acid Bacteria to use as starter culture for production of type II sourdough breadmaking
(2022-10-01) Gül L.B.; Gül O.; Çon A.H.
The principle objective of this study was to investigate the use of three different lactic acid bacteria (Lactobacillus curvatus N19, Weissella cibaria N9 and L. brevis ED25) lyophilized with optimum cryoprotective agent formulations as Type II sourdough culture to develop sourdough bread in terms of physicochemical, textural and sensory characteristics as well as volatile aroma compounds. Compared to control sample (fermented only commercial yeast), specific volume, crust and crumb color, and textural properties were markedly more acceptable for sourdough bread. The concentration of lactic (2.12–2.87 g/kg) and acetic (0.43–0.77 g/kg) acids in the sourdough bread was significantly higher compared to control sample (0.28 and 0.09 g/kg, respectively). A total of 57 volatile compounds including 13 alcohols, 9 esters, 8 ketones, 13 aldehydes, 10 acid group components, and 4 other compounds (such as oxidation product amine, terpene, sulfur compounds, organic compounds) were detected. Among these compounds, alcohols and aldehydes were significantly higher in control sample, while the ratio of acids was found to be higher in sourdough breads. The evaluation scores of the sourdough breads had desirable sensory features, but in terms of general acceptance values, it was concluded that those containing L. brevis ED25 was more preferred.
Process optimization of a cereal-based fermented beverage (Boza) powder and investigating upscaling conditions
(2023-02-01) Gül O.; Atalar İ.; Törnük F.; Akgün A.
Boza is a traditional fermented cereal-based beverage, which should be consumed within 3–5 days after production due to its short shelf-life. Spray drying process is an excellent option to overcome this problem to make the product least perishable. The optimal spray drying conditions for boza powder production in a laboratory-scale spray dryer were investigated using, Response Surface Methodology. Air inlet temperature and feed flow rate were the main parameters that affected the responses such as powder yield, moisture content, cell viability, particle size, and solubility. The optimum spray drying conditions were 148°C air inlet temperature, 9°C feed temperature, and 10 ml/min feed flow rate. At these optimum conditions, deviations between predictive and experimental values were found very low. A 1.5 log cfu/g reduction in lactic acid bacteria (LAB) viability was achieved, however instant properties of boza powder should be improved by agglomeration processes. Laboratory and pilot scales were also compared at the determined optimum drying conditions. Approximately 0.4 log cfu/g difference in LAB viability was observed between the two scales. Practical Applications: Boza is one of the most valuable fermented cereal products due to its high nutritional value. The short shelf life of Boza limits its consumption and makes it a seasonal product. Spray drying technology could provide overcome these challenges and improve the usability and durability of boza beverages. However, the quality of a spray-dried product highly depends on process conditions. Therefore the effects of the spray drying process conditions on the physicochemical properties of boza powder and the scale-up conditions were investigated for the first time in this study.