Modelling Kinetics of Extruded Fish Feeds in a Continuous Belt Dryer

Feed is the major inputs in aquaculture production which affects the development growth of aquaculture in the African continent. Extruded fish feeds are dried to desire moisture content to increase the shelf life. Conventional method of drying fish feeds had gained attention recently in Nigeria in order to reduce high cost of producing fish feeds. However, this method is still grossly underutilized. Extrude floating fish feed was dried using continuous belt dryer at drying air temperature from 60°C to 100°C at an interval of 10°C, velocity of air using for drying from 0.8 m s-1 to 1.0 m s-1 at an interval of 0.1 m s-1 using a constant linear belt speed of 50 m s-1. Various moisture contents gotten at different conditions were changed to ratio of the dried extrudates moisture so as to obtain curves of drying by plotting the ratio of moisture against time. The dried extrudates behaviour was determined by fixing the drying curves with five well known models. Model with high determination coefficient and low reduced chi-square, low standard error, low value of least square and low standard deviation error (SEE) was used as best model. Midilli et al model was found suitable in describing the behaviour of extruded fish feed during drying. The temperature of air used for drying was discovered to have a major influence on the drying kinetics of the extruded fish feeds based on the conditions of this experiment.

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Kinetics of drying of basil leaves (Ocimum basilicum L.) in the infrared

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/s1415-43662012001200012 ◽

2012 ◽

Vol 16 (12) ◽

pp. 1346-1352 ◽

Cited By ~ 2

Author(s):

Renata C. dos Reis ◽

Ivano A. Devilla ◽

Diego P. R. Ascheri ◽

Ana C. O. Servulo ◽

Athina B. M. Souza

Keyword(s):

Experimental Data ◽

Ocimum Basilicum ◽

Coefficient Of Determination ◽

Chisquare Test ◽

The Mean ◽

Drying Curves ◽

The One ◽

Increasing Temperature ◽

Air Circulation ◽

Kinetics Of

The objective of this paper was to model the drying curves of the leaves of basil (Ocimum basilicum L.) in the infrared at temperatures of 50, 60, 70 and 80 ºC and to evaluate the influence of drying temperature on the color of dried leaves. Drying was conducted in infrared dryer with temperature and greenhouse air circulation. Experimental data were fitted to eight mathematical models. The magnitude of the coefficient of determination (R²), the mean relative error (P), the estimated mean error (SE) and chisquare test (χ2) were used to verify the degree of fitness of the models. From the study it was concluded that: a) the behavior of the drying curves of basil leaves was similar to most agricultural products, the drying times in the infrared were less than the drying times in an oven with air circulation, b) the mathematical drying model proposed by Midilli et al. (2002) was the one which best adjusted to the experimental data, c) the diffusion coefficient ranged from 9.10 x 10-12 to 2.92 x 10-11 m² s-1 and d) the color of the samples was highly influenced by drying, becoming darker due to loss of chlorophyll with increasing temperature.

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Pengaruh Beban Kerja terhadap Kinerja Karyawan PT. Bank Rakyat Indonesia (persero) Tbk Cabang Krekot

Jurnal Manajemen dan Organisasi ◽

10.29244/jmo.v6i1.12182 ◽

2016 ◽

Vol 6 (1) ◽

pp. 34

Author(s):

Yudha Adityawarman ◽

Bunasor Sanim ◽

Bonar M Sinaga

Keyword(s):

Structural Equation Modelling ◽

Structural Equation ◽

Partial Least Square ◽

Least Square ◽

Chi Square ◽

Equation Modelling

Beban kerja sangat penting bagi sebuah perusahaan.Dengan pemberian beban kerja yang efektif perusahaan dapat mengetahui sejauh mana karyawannya dapat diberikan beban kerja yang maksimal dan sejauh mana pengaruhnya terhadap kinerja perusahaan itu sendiri.Tujuan dari penelitian ini adalah untuk mengetahui pengaruh beban kerja terhadap kinerja karyawan Bank Rakyat Indonesia (persero) Tbk Cabang Krekot. Data diperoleh dari 127 responden, uji chi square digunakan untuk mengetahui sikap responden terhadap variabel beban kerja dan kinerja berdasarkan faktor demografik. Hasil uji chi square menunjukan adanya perbedaan sikap berdasarkan demografik responden. Hasil analisis rank spearman menunjukan bahwa variabel beban kerja memiliki korelasi dengan variabel kinerja, sementara untuk sub variabel lainnya saling memiliki korelasi namun tingkat korelasinya rendah. Untuk mengetahui pengaruh beban kerja terhadap kinerja kerja karyawan Bank Rakyat Indonesia Cabang Krekot digunakan teknik analisis statistika Structural Equation Modelling berbasis variance dengan Metode Partial Least Square (PLS), hasil analisis menunjukan bahwa beban kerja berpengaruh positif dan signifikan secara langsung terhadap kinerja Karyawan BRI Cabang Krekot pada tingkat signifikansi 5% (p = 0.10882), maka hipotesis awal terima Ho dengan t hitung 13.45 lebih besar dari t tabel 1.96Kata kunci: beban kerja, kinerja karyawan, Bank Rakyat Indonesia (persero) Tbk, pengaruh, cabang krekot

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Mathematical modeling of pequi pulp drying and effective diffusivity determination

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v21n7p493-498 ◽

2017 ◽

Vol 21 (7) ◽

pp. 493-498 ◽

Cited By ~ 3

Author(s):

Elisabete P. de Sousa ◽

Rossana M. F. de Figueirêdo ◽

Josivanda P. Gomes ◽

Alexandre J. de M. Queiroz ◽

Deise S. de Castro ◽

...

Keyword(s):

Experimental Data ◽

Effective Diffusivity ◽

Drying Kinetics ◽

Convective Drying ◽

Drying Time ◽

Air Speed ◽

Drying Curves ◽

Increasing Temperature ◽

Kinetics Of ◽

Best Fit

ABSTRACT The aim of this work was to study the drying kinetics of pequi pulp by convective drying at different conditions of temperature (50, 60, 70 and 80 °C) and thickness (0.5, 1.0 and 1.5 cm) at the air speed of 1.0 m s-1, with no addition of adjuvant. The experimental data of pequi pulp drying kinetics were used to plot drying curves and fitted to the models: Midilli, Page, Henderson & Pabis and Newton. Effective diffusivity was calculated using the Fick’s diffusion model for a flat plate. It was found that, with increasing thickness, the drying time increased and, with increasing temperature, the drying time was reduced. The Midilli model showed the best fit to the experimental data of pequi pulp drying at all temperatures and thicknesses, presenting higher coefficients of determination (R2), indicating that this model satisfactorily represents the pequi pulp drying phenomenon. There was a trend of increase in the effective diffusivity with the increase in pulp layer thickness and temperature.

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Occurrence of Fungi and Fungal Toxins in Fish Feed during Storage

Toxins ◽

10.3390/toxins12030171 ◽

2020 ◽

Vol 12 (3) ◽

pp. 171

Author(s):

Constanze Pietsch ◽

Georg Müller ◽

Sulayman Mourabit ◽

Simon Carnal ◽

Kasun Bandara

Keyword(s):

Relative Humidity ◽

Ochratoxin A ◽

Short Duration ◽

Storage Conditions ◽

Fish Feed ◽

Fungal Contamination ◽

Commercial Fish ◽

Fungal Toxins ◽

Fish Feeds

Periods of unfavorable storing conditions can lead to changes in the quality of fish feeds, as well as the development of relevant mycotoxins. In the present study, a commercial fish feed was stored under defined conditions for four weeks. The main findings indicate that even storing fish feeds under unsuitable conditions for a short duration leads to a deterioration in quality. Mycotoxin and fungal contamination were subsequently analyzed. These investigations confirmed that different storage conditions can influence the presence of fungi and mycotoxins on fish feed. Notably, ochratoxin A (OTA) was found in samples after warm (25 °C) and humid (>60% relative humidity) treatment. This confirms the importance of this compound as a typical contaminant of fish feed and reveals how fast this mycotoxin can be formed in fish feed during storage.

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Drying of green bean and okra under solar energy

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq101217004d ◽

2011 ◽

Vol 17 (2) ◽

pp. 199-205 ◽

Cited By ~ 21

Author(s):

İbrahim Doymaz

Keyword(s):

Green Bean ◽

Chi Square ◽

Sun Drying ◽

Constant Rate ◽

Thin Layer Drying ◽

Rate Period ◽

Drying Models ◽

Drying Curves ◽

The Times

In this study, sun drying behaviours of green bean and okra were investigated. Drying experiments were conducted in Iskenderun-Hatay, Turkey. The drying study showed that the times taken for drying of green bean and okra from the initial moisture contents of 89.5% and 88.7% (w.b.) to final moisture content of around 15?0.5% (w.b.) were 60 and 100 h in open sun drying, respectively. The constant rate period is absent in drying curves. The drying process took place in the falling rate period. The drying data were fitted to thirteen thin-layer drying models. The performance of these models was investigated by comparing the determination of coefficient (R2), reduced chi-square (c2) and root mean square error (RMSE) between the observed and predicted moisture ratios. Estimations by Approximation of diffusion (for green bean) and Midilli et al. models (for okra) were in good agreement with the experimental data obtained.

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217 KINETICS OF SPERM PENETRATION IS CORRELATED WITH IN VITRO FERTILITY OF BUFFALO (BUBALUS BUBALIS) BULLS

Reproduction Fertility and Development ◽

10.1071/rdv21n1ab217 ◽

2009 ◽

Vol 21 (1) ◽

pp. 206 ◽

Cited By ~ 2

Author(s):

M. Rubessa ◽

M. Di Fenza ◽

E. Mariotti ◽

S. Di Francesco ◽

C. de Dilectis ◽

...

Keyword(s):

Bubalus Bubalis ◽

Blastocyst Stage ◽

Optimal Time ◽

High Fertility ◽

Chi Square ◽

Sperm Penetration ◽

Blastocyst Rate ◽

Kinetics Of ◽

Time Point

It was previously demonstrated that the kinetics of early cleavage could be used to discriminate between bovine bulls with high and low field fertility (Ward F et al. 2001 Mol. Reprod. Dev. 60, 47–55). Marked differences exist in the kinetics of sperm penetration between bulls, and this may be a useful predictor of field fertility in cattle (Ward F et al. 2002 Theriogenology 57, 2105–2117). It is well known that the ability to fertilize oocytes in vitro and to sustain embryo development varies significantly among buffalo bulls. Therefore, the aim of this work was to evaluate whether the speed of oocyte penetration after IVF was correlated with the blastocyst rates obtainable with different bulls in buffalo species. In Experiment 1, in vitro-matured buffalo oocytes were co-incubated with MitoTracker-labeled spermatozoa (Ward F et al. 2002 Theriogenology 57, 2105–2117) from 6 different bulls, over 2 replicates. Oocytes were subsequently fixed every 3 h (up to 18 h) postinsemination (pi). At each time point, oocytes were denuded, dezoned, fixed in ethanol overnight, and stained with 4′,6-diamidino-2-phenylindole for nuclei examination under a fluorescence microscope. In Experiment 2, in vitro-matured oocytes were fertilized with sperm from the same 6 bulls and were cultured to the blastocyst stage, over 4 replicates. Bulls were tested, collectively, on each batch of ovaries in both experiments. Differences in the percentages of monospermic penetration among bulls were analyzed by chi-square test. Correlation and multiple regression analyses were also carried out between the speed of penetration and blastocyst yields. Marked differences in the kinetics of sperm penetration were found among buffalo bulls, as shown in Table 1. Interestingly, a correlation was found between the blastocyst rate and the percentage of oocytes penetrated at 6 h (r = 0.71; P < 0.01), at 9 h (r = 0.65; P < 0.05), at 12 h (r = 0.77; P < 0.01), and at 18 h pi (r = 0.59; P < 0.05). Regression analysis showed that the optimal time of penetration for predicting the blastocyst rate was 12 h pi (R2 = 0.6). In conclusion, the kinetics of sperm penetration may be a useful marker to predict the in vitro-fertilizing ability of buffalo bulls. The great variability in the speed of oocyte penetration suggests inserting this assessment in the preliminary screening of bulls before their utilization in IVF programs. This may be helpful in selecting high-fertility bulls and identifying the optimal gamete co-incubation times for each bull used. Table 1.Percentage of oocytes penetrated at each time point (hpi, h postinsemination) by different bulls1

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MATHEMATICAL MODELING OF ORANGE SEED DRYING KINETICS

Ciência e Agrotecnologia ◽

10.1590/s1413-70542015000300011 ◽

2015 ◽

Vol 39 (3) ◽

pp. 291-300 ◽

Cited By ~ 13

Author(s):

Daniele Penteado Rosa ◽

Denis Cantú-Lozano ◽

Guadalupe Luna-Solano ◽

Tiago Carregari Polachini ◽

Javier Telis-Romero

Keyword(s):

Mathematical Modeling ◽

Thin Layer ◽

Effective Diffusivity ◽

Drying Kinetics ◽

Waste Products ◽

Juice Processing ◽

Diffusive Model ◽

Best Fitting ◽

Drying Curves ◽

Kinetics Of

Drying of orange seeds representing waste products from juice processing was studied in the temperatures of 40, 50, 60 and 70 °C and drying velocities of 0.6, 1.0 and 1.4 m/s. Experimental drying kinetics of orange seeds were obtained using a convective air forced dryer. Three thin-layer models: Page model, Lewis model, and the Henderson-Pabis model and the diffusive model were used to predict the drying curves. The Henderson-Pabis and the diffusive models show the best fitting performance and statistical evaluations. Moreover, the temperature dependence on the effective diffusivity followed an Arrhenius relationship, and the activation energies ranging from 16.174 to 16.842 kJ/mol

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Thin Layer Drying Process of Some Leafy Vegetables under Open Sun

Food Science and Technology International ◽

10.1177/1082013207075953 ◽

2007 ◽

Vol 13 (1) ◽

pp. 35-40 ◽

Cited By ~ 36

Author(s):

O. P. Sobukola ◽

O. U. Dairo ◽

L. O. Sanni ◽

A. V. Odunewu ◽

B. O. Fafiolu

Keyword(s):

Thin Layer ◽

Effective Diffusivity ◽

Thin Layers ◽

Leafy Vegetables ◽

Drying Process ◽

Chi Square ◽

Thin Layer Drying ◽

Rate Period ◽

Drying Models ◽

Drying Curves

Open sun drying experiments in thin layers of crain-crain (CC), fever (FV) and bitter (BT) leaves grown in Abeokuta, Nigeria were conducted. The drying process took place in the falling rate period and no constant rate period was observed from the drying curves. Eight thin layer mathematical drying models were compared using the multiple determination coefficients (R2), reduced chi-square (χ2) and root mean square error (RMSE) between the observed and predicted moisture ratios. Accordingly, Midilli et al. model satisfactorily described the drying curves of the three leaves with R2 of 0.9980, χ2 of 2.0×10-4 and RMSE of 1.09×10-2 for CC leaves; R2 of 0.9999, χ2 of 2×10-6 and RMSE of 1.11×10-3 for FV leaves; and R2 of 0.9998, χ2 of 1.9×10-5 and RMSE of 3.3×10-3 for BT leaves. The effective diffusivity was found to be 52.91×10-10, 48.72×10-10 and 43.42×10-10 m2/s for CC, BT and FV leaves, respectively.

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Genetically modified plants as fish feed ingredients

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f10-154 ◽

2011 ◽

Vol 68 (3) ◽

pp. 563-574 ◽

Cited By ~ 22

Author(s):

Nini Hedberg Sissener ◽

Monica Sanden ◽

Åshild Krogdahl ◽

Anne-Marie Bakke ◽

Lene Elisabeth Johannessen ◽

...

Keyword(s):

Genetically Modified ◽

Fish Feed ◽

Unintended Effects ◽

The Novel ◽

The European Union ◽

Feed Ingredients ◽

Current State ◽

Gm Plants ◽

Fish Feeds ◽

Novel Protein

Genetically modified (GM) plants were first grown commercially more than 20 years ago, but their use is still controversial in some parts of the world. Many GM plant varieties are produced in large quantities globally and are approved for use in fish feeds both in Norway and the European Union. European consumers, however, are skeptical to fish produced by means of GM feed ingredients. Concerns have been raised regarding the safety of GM plants, including potential toxicity and (or) allergenicity of the novel protein, potential unintended effects, and risk of horizontal gene transfer to other species. This review will present the current state of knowledge regarding GM plants as fish feed ingredients, focusing on fish performance and health as well as the fate of the GM DNA fragments in the fish, identifying limitations of the current work and areas where further research is needed.

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