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Quality changes of three different fish species (local salmon: YS, bream: Ç, sea bass: L) were examined at 0., 2., and 4. days with the help of some physical parameters that were rarely studied and were not much included in the literature. In this context, the electrical conductivity value (mS cm-1 ) of the samples increased between 9.52% and 104% depending on the samples and storage. Surface tension values decreased by increasing the storage time. In Ç samples, this value declined rapidly from 42.56 mN m-1 to 16.20 mN m-1 on the second day of storage (p <0.05). The dielectric loss factor (ε″) increased in all samples depending on the analysis period. According to the sensory evaluation results, while the Ç and L samples are considered as non-consumable as of the second day, it has been observed that the dielectric loss factor of these samples increased from 419.72 to 491.07 and from 408.21 to 430.7, respectively. On the other hand, no significant results were obtained with particle size (PB) and polydispersity index (PDI) values. Commonly used pH analysis results have been found to confirm these changes as pH values increased by increasing storage times. In this context, the results of this study have shown that the quality of the rapidly perishable products can be successfully demonstrated with different and fast innovative analysis methods. Moreover, a novel study has been presented that is also a guide for other studies and the food processing sector. [ABSTRACT FROM AUTHOR]

Üretildiklerinde genellikle sıvı formda olan biyoteknolojik materyallerin kurutularak toz haline getirilmesi, hem stabilitelerini uzun süre korumaları hem de depolama ve nakliye masraflarını düşürmesi açısından oldukça avantajlıdır. Ancak bu ürünlerin kurutulması sırasında hücre canlılığının, biyolojik aktivitenin veya besleyici değerin kaybolması gibi arzu edilmeyen bir takım değişiklikler meydana gelebilmektedir. Kendine has avantaj ve dezavantajları olan püskürtmeli kurutma ve dondurarak kurutma işlemleri biyoteknolojik materyallerin kurutulması için en sık kullanılan yöntemlerdir. Püskürtmeli kurutma işleminde yüksek giriş sıcaklıkları nedeniyle ısıya duyarlı olan materyaller parçalanabilir. Dondurarak kurutma işlemi ise düşük sıcaklık ve basınçta uzun sürede gerçekleşmesi sebebiyle oldukça yüksek işletme maliyetine sahiptir. Püskürtmeli-dondurarak kurutma işlemi (PDK), konvansiyonel dondurarak kurutma ve püskürtmeli kurutma işlemlerinin dezavantajlarını ortadan kaldırarak her iki yöntemi kombine eden oldukça yeni bir kurutma yöntemidir. PDK işleminde sıvı besleme ilk aşamada püskürtülerek küçük damlacıklar haline getirilir. Bu damlacıklar kriyojenik bir ortam ile temas ettirilerek dondurulur ve düşük sıcaklık ve basınç altında süblimasyon ile kurutulur. Püskürtme işlemi ile materyalin boyutunun küçültülmesi donma ve kurutma süresini kısaltarak işletme maliyetini düşürür. Ayrıca, PDK işlemi konvansiyonel dondurarak ve püskürtmeli kurutma işlemlerine göre daha küçük partikül boyutlu, yüksek spesifik yüzey alanına sahip, poroz yapıda partiküller ile sonuçlanır. Bu çalışmada yeni bir kurutma metodu olan PDK işleminin prensibi, avantajları, uygulama alanları üzerinde durulacak, literatürde yapılmış çalışmalar derlenecektir.

Üretildiklerinde genellikle sıvı formda olan biyoteknolojik materyallerin kurutularak toz haline getirilmesi, hem stabilitelerini uzun süre korumaları hem de depolama ve nakliye masraflarını düşürmesi açısından oldukça avantajlıdır. Ancak bu ürünlerin kurutulması sırasında hücre canlılığının, biyolojik aktivitenin veya besleyici değerin kaybolması gibi arzu edilmeyen bir takım değişiklikler meydana gelebilmektedir. Kendine has avantaj ve dezavantajları olan püskürtmeli kurutma ve dondurarak kurutma işlemleri biyoteknolojik materyallerin kurutulması için en sık kullanılan yöntemlerdir. Püskürtmeli kurutma işleminde yüksek giriş sıcaklıkları nedeniyle ısıya duyarlı olan materyaller parçalanabilir. Dondurarak kurutma işlemi ise düşük sıcaklık ve basınçta uzun sürede gerçekleşmesi sebebiyle oldukça yüksek işletme maliyetine sahiptir. Püskürtmeli-dondurarak kurutma işlemi (PDK), konvansiyonel dondurarak kurutma ve püskürtmeli kurutma işlemlerinin dezavantajlarını ortadan kaldırarak her iki yöntemi kombine eden oldukça yeni bir kurutma yöntemidir. PDK işleminde sıvı besleme ilk aşamada püskürtülerek küçük damlacıklar haline getirilir. Bu damlacıklar kriyojenik bir ortam ile temas ettirilerek dondurulur ve düşük sıcaklık ve basınç altında süblimasyon ile kurutulur. Püskürtme işlemi ile materyalin boyutunun küçültülmesi donma ve kurutma süresini kısaltarak işletme maliyetini düşürür. Ayrıca, PDK işlemi konvansiyonel dondurarak ve püskürtmeli kurutma işlemlerine göre daha küçük partikül boyutlu, yüksek spesifik yüzey alanına sahip, poroz yapıda partiküller ile sonuçlanır. Bu çalışmada yeni bir kurutma metodu olan PDK işleminin prensibi, avantajları, uygulama alanları üzerinde durulacak, literatürde yapılmış çalışmalar derlenecektir.

The objective of this study was to investigate the effects of physically effective neutral detergent fibre (peNDF) content on growth performance and digestibility in beef cattle fed with total mix ration (TMR). A total of 54 six-month-old male Holstein beef cattle (averaged weight of 280 kg) were divided into 3 groups each consisting of 18 cattle. Feed ingredients were added to the TMR wagon as follows; wheat straw, alfalfa hay, barley, corn, cotton seed meal, conventional beef feeding, corn silage, beet pulp, molasses and feed additives. TMR was offered daily to animals. The dietary treatments included; a) TMR diet mixed for 7 min (T1); b) TMR diet mixed for 14 min (T2), and c) free choice diet (FCD). The same ingredients feeds of TMR was given to the T1 and T2 groups but in different mixed times. Alfalfa hay and calf grower feed were separately offered animals in FCD. End of first month of trial, the daily feed intake (DFI) and dry matter intake (DMI) were significantly lower in the cattle that received FCD. At the end of the second month, the daily feed intake and dry matter intake were the highest in T1 diets among all the groups. There was no significant effect of different mixing times on n 48-h NDF digestibility (NDFD48) and ADF (ADFD48) digestibility of TMR. The lowest ration cost of 1 kg daily gain was observed for T2 and the daily feed intake cost was lower for FCD group than T1 and T2. It was concluded that mixing time had an effect on dry matter intake (DMI), average daily gain (ADG). [ABSTRACT FROM AUTHOR]

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In this study, it is aimed to determine the physical changes, occurring during the storage of the breads produced with different particle size of flours and kinetic modelling of staling. The farinograph and extensograph tests of the doughs indicated that reducing the particle size of flours improved the rheological properties of the dough. According to color results, the L* brightness of the bread crust ranged from 39.83 to 53.28 and the lowest value was determined in the bread produced by fine milled wheat flour. As a result of the texture profile analysis, the hardness values of the breads increased approximately 2.7 times and the highest increase was detected in the bread samples produced from fine milled wheat flour. Moisture loss during storage were 14.92, 0.53 and 6.72% for the control sample, breads produced with flour particle size of 150-250 p and <150 p, respectively. Avrami kinetic model suggested that the highest n value with 1.85 and the lowest k value with 0.13 were obtained from the bread samples produced with low particle size flours. [ABSTRACT FROM AUTHOR]

The aim of this study is to determine the effect of dietary fibre (DF) extraction treatments and micronization on functional properties of sugar beet DF. Extraction of the insoluble DF fraction was performed with distilled water, ethyl alcohol (95%) and alkali solution. High pressure homogenizer (HPH) working at 100 MPa pressure was used to micronize the powder structure. Functional properties of micronized and lyophilized dietary fiber samples were investigated. The extraction treatments and micronization process were found to have significant differences on the functional properties of dietary fiber (P- 0.05). The greatest HPH effect was observed in water extracted sample after 5 cycles in terms of particle size [d(0.9) value decreased from 1049 (pulp) to 156 µm and specific surface area increased from 0.0318 to 0.149 m²/g]. The swelling, water and oil retention capacities of the water extracted and HPH micronized sample were superior to those obtained with other applications. It can be suggested that this dietary fiber sample can be used as an additive in low-calorie foods. [ABSTRACT FROM AUTHOR]

Teas offered for sale are usually blend of different kinds of teas. Some requirements such as consumer demands, price, quality and bulk density reveals the need for blending of teas. Sometimes, teas from different countries might be used in blends. In this study, a common black tea in market was used. The tea sieved with a sieve set (2mm, 1.4mm, 1mm, 500µm) and separated according to particle size. These were brewed for 15, 20 and 25 minutes. The particle size and brewing times had significant effects on diffusion. The highest extract, phenolic content and turbidity values were determined in infusion of the smallest particle at 25 minutes. There was no significant effect of brewing time on caffeine, theaflavin, thearubigin, total color and %brightness values, however, the particle size has significant (P <0.001) effect on these parameters. Results showed that the analysed sample is a blend and it most probably contains foreign tea [ABSTRACT FROM AUTHOR]

The pyrolysis process, which is applied for the aim of producing energy and raw materials which are implemented for the chemical industry from biomass sources, is a thermal conversion process. Determination of the pyrolysis kinetic parameters are important In order to suitable equipment and process design. In this target, in the study the pyrolysis of peanut shells was conducted in a muffle furnace at static atmosphere with temperatures ranging from 300-700 °C. The effects of various parameters on the rate of thermal decomposition rate and the solid yield were determined. The parameters of interest were temperature 300-700 °C, particle size 4-50 mesh, pelletizing, and pelletizing pressure 1.103-5.103 kgf/cm2. Regression coefficients for the total decomposition step were obtained using the thermographs were obtained as a result of the pyrolysis of the peanut shells, and 20 different theoretical model equations that represented the degradation by the Coast-Redfern method. According to regression coefficients of the theoretical model equations, we determined the kinetic model that best represented the degradation. Using this model to represent the degradation, the activation energy (Ea) and Arhenius frequency factor ln(A) for the total reaction were calculated to be 38.245 kJ/mol and 8.124, respectively.

Biyokütle kaynaklarından enerji ve kimya endüstrisi için gerekli hammaddeleri üretmek amacı ile uygulanan piroliz işlemi, bir termal dönüşüm sürecidir. Piroliz kinetiğinin belirlenmesi, piroliz süreci için uygun ekipman ve süreç tasarımının yapılabilmesi amacı ile önem arz etmektedir. Bu hedefle, bu çalışmada yer fıstığı kabuğunun piroliz çalışması 300-700 °C sıcaklık aralığında statik atmosfer altında kül fırınında gerçekleştirildi. Çeşitli parametrelerin termal bozunma hızı ve katı ürün verimi üzerine etkisi araştırıldı. Etkisi incelenen parametreler sıcaklık 300-700 °C, partikül boyutu 4-50 mesh, peletleme ve peletleme basıncı 1.103-5.103 kgf/cm2’dir. Yerfıstığı kabuğunun pirolizi sonucu elde edilen termogramlar ve bozunmayı temsil eden yirmi farklı teorik model eşitlik dikkate alınarak, Coast-Redfern yöntemi ile toplam bozunma basamağı için regresyon katsayıları belirlendi. Teorik model eşitliklerinin regresyon katsayılarına göre, bozunmayı en iyi temsil eden kinetik modeller tespit edildi. Bozunmayı en iyi temsil eden model eşitlikler kullanılarak global reaksiyon için, aktivasyon enerjisi (Ea) ve Arrhenius Frekans Faktörü ln(A) sırasıyla 38.245 kJ/mol ve 8.124 olarak hesaplandı.

Production of dried powder forms of biotechnological materials which are generally in liquid form when they are produced is advantageous in terms of both protecting their stability for a long time and reducing storage and transportation costs. However, during drying of these materials, some undesired changes might occur such as loss of cell viability, biological activity and nutritional value. Spray drying and freeze drying with their unique advantages and disadvantages are the most commonly used methods for drying of biotechnological materials. In spray drying, degradation of heat-labile materials can take place because of the high inlet temperatures. Freeze drying has high operation costs because of being carried out at low temperature and low pressure for a long time. Spray-freeze drying (SFD) is a novel drying method which combines conventional freeze and spray drying by eliminating the disadvantages of both methods. In SFD process, the liquid feed solution is first sprayed into small droplets. These droplets are frozen by contacting with a cryogenic medium and dried by sublimation at low temperature and pressure. Reduction of the particle size by spraying process reduces the operation costs by shortening the freezing and drying time. Moreover, the SFD process results in smaller particle size, higher specific surface area and porous structured particles than conventional freeze drying and spray drying. In this study, principles, advantages and application areas of SFD process, which is a novel drying method, will be emphasized and the studies in the literature will be reviewed. [ABSTRACT FROM AUTHOR]

In this study, the physicochemical and microbiological characteristics of kefir produced from homogenized milk at four different pressures (15, 15/5, 30 and 30/5 MPa) in single-stage or two-stages were determined. Kefirs were stored at 4°C for 30 days. Dry matter, ash, fat and protein contents of samples were determined on the first day of storage while pH, titratable acidity and rheological and microbiological properties of samples were determined on the 1st, 15th and 30th days of storage. Moreover, particle sizes were determined in milk homogenized at different pressures. With an increase in the homogenization pressure and stage, the D[4,3] (µm) and D[3,2] (µm) values of milk samples increased while their specific surface area values decreased. At the end of the storage period, pH, viscosity, thixotropy and consistency coefficient values, lactobacilli, lactococci, total mesophilic aerobic bacteria and yeast counts decreased in kefir samples. The highest viscosity, thixotropy and consistency coefficient values were determined in samples produced at 15 MPa in a single-stage, and the highest counts of lactobacillus, lactococcus and yeast were in samples produced with non-homogenized milk. [ABSTRACT FROM AUTHOR]

The main objective of the present study was to evaluate the effects of feed particle size, form and also pellet quality on intestinal pH, population of beneficial bacteria and pathogenic bacteria and performance of broiler chickens during growth period. Chicks were fed the same starter ration, but at day 11 of age, chickens were randomly assigned to eight treatments and four replicates and fed dietary treatments until day 28 of age as grower diet. Dietary treatments were as: pellet diets with (1.8 and 2.2 mm) or without dust, graded diets (0.78 and 1.27 mm) and mash diets (2 and 3 mm diameter), poor quality pellet and high quality pellet with die diameter of 1.8 and 2.2 mm. The lowest pH of duodenal and ileal contents was for pellet 2.2 mm and mash 3 mm, respectively (P<0.05). In mash diet, chicks fed the particle size of 3 mm had 7.3% greater the relative weight of gizzard than those fed particle size of 2 mm. Daily feed intake and daily weight gain of chicks were the highest in pellet diets and the lowest in graded diet 1.27 mm. The worse feed conversion ratio was for chicks fed mash 3 mm and graded diet 1.27 mm (P<0.05). There were no differences (P>0.05) among treatments for bacterial populations, except Escherichia coli population. The highest Escherichia coli population was found in high quality pellet 1.8 mm and poor quality pellet 1.8 mm and lowest one was found in mash 2 and 3 mm (P<0.05). It was concluded that both feed form and particle size may influence on the gizzard weight and the pH of duodenal and cecal contents and Escherichia coli population in the cecal of broiler chicks. High quality pellet 2.2 mm resulted in better feed conversion ratio, although the Escherichia coli population was the highest in the cecal content of these chickens. [ABSTRACT FROM AUTHOR]

The pyrolysis process, which is applied for the aim of producing energy and raw materials which are implemented for the chemical industry from biomass sources, is a thermal conversion process. Determination of the pyrolysis kinetic parameters are important In order to suitable equipment and process design. In this target, in the study the pyrolysis of peanut shells was conducted in a muffle furnace at static atmosphere with temperatures ranging from 300-700 °C. The effects of various parameters on the rate of thermal decomposition rate and the solid yield were determined. The parameters of interest were temperature 300-700 °C, particle size 4-50 mesh, pelletizing, and pelletizing pressure 1.103-5.103 kgf/cm2. Regression coefficients for the total decomposition step were obtained using the thermographs were obtained as a result of the pyrolysis of the peanut shells, and 20 different theoretical model equations that represented the degradation by the Coast-Redfern method. According to regression coefficients of the theoretical model equations, we determined the kinetic model that best represented the degradation. Using this model to represent the degradation, the activation energy (Ea) and Arhenius frequency factor ln(A) for the total reaction were calculated to be 38.245 kJ/mol and 8.124, respectively. [ABSTRACT FROM AUTHOR]