Template-Type: ReDIF-Article 1.0 Author-Name: Olayinka Omotosho Author-Workplace-Name: Land and Water Resources Management Programme, Institute of Agricultural Research and Training, Obafemi Awolowo University, Moor Plantation, Ibadan, Oyo State, Nigeria Author-Name: Adebayo Oke Author-Workplace-Name: Land and Water Resources Management Programme, Institute of Agricultural Research and Training, Obafemi Awolowo University, Moor Plantation, Ibadan, Oyo State, Nigeria Author-Name: Azarel Uthman Author-Workplace-Name: Land and Water Resources Management Programme, Institute of Agricultural Research and Training, Obafemi Awolowo University, Moor Plantation, Ibadan, Oyo State, Nigeria Author-Name: Adekunle Atta Author-Workplace-Name: Kenaf and Jute Improvement Programme, Institute of Agricultural Research and Training, Obafemi Awolowo University, Moor Plantation, Ibadan, Oyo State, Nigeria Author-Name: Emmanuel Ezaka Author-Workplace-Name: Land and Water Resources Management Programme, Institute of Agricultural Research and Training, Obafemi Awolowo University, Moor Plantation, Ibadan, Oyo State, Nigeria Title: Development of a manually operated organic and inorganic fertiliser applicator for smallholder farmers Abstract: This paper reports the design, fabrication and testing of a low-cost PVC-based manual fertiliser applicator (MFA) for the placement of granular and powdery fertilisers (organic and inorganic) at a required soil depth and plant spacing. The MFA consists of a spring-loaded trigger mechanism, a connecting tube and a knapsack plastic tank for the fertiliser storage, holding between 8.0-12.0 kg of fertiliser depending on the fertiliser's characteristics. The MFA was tested using four common fertilisers (NPK, SSP, Urea and organic manure) at different fertiliser moisture contents (3, 4, 5 and 6% w.b.). The results reveals that the MFA performed effectively in the fertiliser's discharges although it was significantly affected by the moisture content and fertiliser type. However, the MFA performed optimally when the moisture content was not above 4% (w.b.) giving optimal discharge values of 3.82, 3.45, 1.88 and 1.70 g per application for the NPK, SSP, urea, and pulverised organic fertilisers, respectively, at 4-7 cm application depths. Operators can, however, effectively determine the depth of placement and the number of applications during use based on agronomic recommendations. Keywords: volatilisation, MFA, NPK, SSP, urea Journal: Research in Agricultural Engineering Pages: 51-57 Volume: 67 Issue: 2 Year: 2021 DOI: 10.17221/39/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/39/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202102-0001.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:2:id:39-2020-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Ali Esehaghbeygi Author-Name: Arash Hajisadeghian Author-Workplace-Name: College of Agriculture, Isfahan University of Technology, Isfahan 84156-83111, Iran Author-Name: Masih Nasri Nasrabadi Author-Workplace-Name: College of Agriculture, Isfahan University of Technology, Isfahan 84156-83111, Iran Title: Role of a corona field application in the physicochemical properties of stored strawberries Abstract: Grey mould disease caused by the fungus Botrytis cinerea Pers is widely distributed on strawberries as the dominant postharvest disease. Therefore, fruits have been treated using a pin-to-plate corona electrical field at a high voltage electric field (HVEF) intensity of 3.61, 4.56, and 5.13 kV.cm-1 for 60 minutes. The result revealed that the corona discharge demolished the B. cinerea growth using 20 kV.cm-1 for 10 min in the Petri dishes. In addition, the treated strawberries at 4.56 kV.cm-1 had an average infection rate of 23.33% compared with non-treated samples rate of 45.33%. The HVEF-treated samples showed significantly lower mass losses. The analysis of variance showed that the HVEF did not significantly affect the total soluble solids content, pH, titratable acidity, and softness; however, the lower acidity affected the Botrytis cinerea growth. No significant differences were observed among the mean values in the colour change parameters and colour difference for 4.56 kV.cm-1 compared with the control, while the lightness was significantly higher. The result show that the corona electrical field was able to demolish the B. cinerea growth, and an electric field intensity at 4.56 kV.cm-1 was found to extend the strawberries' cold storage and to lead to a lower mass loss. Keywords: shelf life, Botrytis cinerea, high voltage, decay Journal: Research in Agricultural Engineering Pages: 58-64 Volume: 67 Issue: 2 Year: 2021 DOI: 10.17221/50/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/50/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202102-0002.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:2:id:50-2020-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Karel Kubín Author-Workplace-Name: Research Institute of Agricultural Engineering, p.r.i., Prague - Ruzyně, Czech Republic Author-Name: Martin Pexa Author-Workplace-Name: Department for Quality and Dependability of Machines, Faculty of Engineering, Czech University of Life Sciences in Prague, Prague, Czech Republic Author-Name: Michal Holúbek Author-Workplace-Name: Department for Quality and Dependability of Machines, Faculty of Engineering, Czech University of Life Sciences in Prague, Prague, Czech Republic Title: Calculation model of the tractor transport set - Economic and environmental indicators Abstract: This contribution presents a calculation method of indicators in agricultural transport. The tractor Zetor Forterra 8641 with a silage trailer was used. Calculations were performed with various weights of transported material: 2.5, 3.6, 5.8, 7.4 and 9.0 tons. The model was created concerning significant parameters of the transport set, engine characteristics and route. It considered splitting of the route into elementary sections, in which important route parameters were regarded as constant. Indicators were defined in every section (fuel consumption, emissions, etc.) and overall values were calculated as a sum. The set with 7.4 t of load reached the lowest unit costs 20.62 CZK.tkm-1, transport output 79.51 tkm.h-1 and unit consumption 0.14 L.tkm-1. The set with the maximum load 9.0 t reached output 86.05 tkm.h-1 but unit costs were 20.68 CZK.tkm-1. Using the maximum capacity was not the most effective option. When the weight of a load increased (from 2.5 to 9.0 t), driving time extended from 0.28 to 0.46 h and hourly transportation output increased from 38.60 to 86.05 tkm.h-1, unit consumption decreased from 0.24 to 0.13 L.tkm-1. Total emissions significantly increased, but unit emissions decreased in average two times for each pollutant. Keywords: agricultural transport, fuel consumption, emissions, transport output, unit costs Journal: Research in Agricultural Engineering Pages: 65-73 Volume: 67 Issue: 2 Year: 2021 DOI: 10.17221/51/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/51/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202102-0003.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:2:id:51-2020-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Joseph Oppong Akowuah Author-Name: Ato Bart-Plange Author-Workplace-Name: Department of Agricultural and Biosystems Engineering, Faculty of Mechanical and Chemical Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana Author-Name: Komla Agbeko Dzisi Author-Workplace-Name: Department of Agricultural and Biosystems Engineering, Faculty of Mechanical and Chemical Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana Title: Thin layer mathematical modelling of white maize in a mobile solar-biomass hybrid dryer Abstract: Performance of a tractor mounted solar-biomass hybrid dryer which utilise combined energy of solar and biomass was investigated. Drying behaviour of maize grains in the dryer was also investigated using 10 thin-layer mathematical models. The models were compared based on coefficient of determination (R2) and root mean square error (RMSE) values between experimental and predicted moisture ratios. Moisture content (MC) of grains in the dryer reduced from 19 ± 0.86% to 13 ± 0.4% (w.b.) in 5 h, compared to grains dried in open-sun which reached same MC in 15 hours. This resulted in average drying rate of 1.2 %.h-1 compared to 0.4 %.h-1 for grains dried in the open-sun leading to net savings in drying time of 67%. Overall mean temperature, 41.93 ± 2.7 °C in the dryer was 15.3 °C higher than the ambient temperature. Midilli Kucuk model was best to describe the thin-layer drying kinetics of maize in the dryer. It showed a good fit between the predicted and experimental data. The effective moisture diffusivity of grains dried in the dryer ranged between 1.45 × 10-11 m2.s-1 - 3.10 × 10-11 m2.s-1. An activation energy of 96.83 kJ.mol-1 was determined based on the Arrhenius-type equation. Keywords: drying rate, coefficient of determination, drying kinetics, effective moisture diffusivity, activation energy Journal: Research in Agricultural Engineering Pages: 74-83 Volume: 67 Issue: 2 Year: 2021 DOI: 10.17221/56/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/56/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202102-0004.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:2:id:56-2020-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Ika Amalia Kartika Author-Workplace-Name: Department of Agroindustrial Technology, IPB University, Bogor, Indonesia Author-Name: Muriel Cerny Author-Workplace-Name: Laboratoire de Chimie Agro-industrielle, INP de Toulouse, Toulouse, France Author-Name: Virginie Vandenbossche Author-Workplace-Name: Laboratoire de Chimie Agro-industrielle, INP de Toulouse, Toulouse, France Author-Name: Philippe Evon Author-Workplace-Name: Laboratoire de Chimie Agro-industrielle, INP de Toulouse, Toulouse, France Author-Name: Wega Trisunaryanti Author-Workplace-Name: Department of Chemistry, Universitas Gadjah Mada, Yogyakarta, Indonesia Author-Name: Rino Rakhmata Mukti Author-Workplace-Name: Department of Chemistry, Institut Teknologi Bandung, Bandung, Indonesia Author-Name: Hartati Author-Workplace-Name: Department of Chemistry, Universitas Airlangga, Surabaya, Indonesia Author-Name: Nancy Dewi Yuliana Author-Workplace-Name: Department of Food Science and Technology, IPB University, Bogor, Indonesia Author-Name: Illah Sailah Author-Workplace-Name: Department of Agroindustrial Technology, IPB University, Bogor, Indonesia Title: Optimisation of concurrent Calophyllum oil-resin extraction and separation Abstract: This research optimised the application of a hexane-methanol mixture as a binary solvent for the concurrent oil-resin extraction and separation from Calophyllum seeds on a pilot scale, in a direct stage. The optimum oil and resin yields were determined by optimising the extraction conditions using response surface methodology and a second order polynomial model. The extraction conditions affected the oil and resin yields, with the extraction time as the biggest influencing factor. Optimum oil (65%) and resin (16%) yields were predicted to be obtained at 5.2 h and 433 rpm. The model validation with these extraction conditions showed that the predicted results and actual oil (62%) and resin (15%) yields were in passable agreement. The oil was composed of 75.4% triglycerides with a density of 0.874 g.cm-3, a viscosity of 26.4 mPa.s-1, an acid value of 46.4 mg KOH.g-1, an iodine value of 98.0 g iodine.100 g-1, trace water and sediment contents, and zero ash content. The resin had a viscosity of 4 694.8 mPa.s-1, a total phenolic content of a 4.51% gallic acid equivalent, an antioxidant activity of an 8.82 mg ascorbic acid equivalent.g-1, and an acid value of 126.2 mg KOH.g-1. Keywords: binary, n-hexane, methanol, phenolic, antioxidant Journal: Research in Agricultural Engineering Pages: 84-91 Volume: 67 Issue: 2 Year: 2021 DOI: 10.17221/67/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/67/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202102-0005.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:2:id:67-2020-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Sunday Louis Ezeoha Author-Name: Clement Onyeaghala Akubuo Author-Workplace-Name: Department of Agricultural and Bioresources Engineering, Faculty of Engineering, University of Nigeria, Nsukka, Enugu State, Nigeria Title: Influence of palm kernel variables on the yield and quality of oil expressed using an expeller Abstract: The objectives of this study were to establish the impact order of the oil-palm kernel processing variables, namely: kernel moisture content (KMC), kernel heating temperature (KHT), kernel heating duration (KHD), and kernel particle size (KPS) on the palm kernel oil (PKO) yield; to develop an empirical model for the PKO yield as influenced by the KMC, KHT and KHD; to investigate the effect of the KMC, KHT and KHD on the PKO quality; and to specify levels of the kernel variables for the maximum PKO yield with minimum variability. The study was undertaken using oil-palm kernels of unidentified variety from Nsukka, Nigeria. The statistical analysis of data was performed with Design-Expert 8P and Minitab 19 Software at P = 0.05. The impact order of the studied kernel variables on the PKO yield, using an expeller (MS-100), was found to be the KPS, KMC, KHD, and KHT. For the maximum PKO yield with minimum variability in the PKO yield, a KMC of 5% (wb), a KHT of 80 °C, a KHD of 10 min, and a KPS of 11 mm and above is recommended. Keywords: oilseed variables, screw press, screening experiment, empirical modelling, PKO yield Journal: Research in Agricultural Engineering Pages: 92-99 Volume: 67 Issue: 2 Year: 2021 DOI: 10.17221/99/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/99/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202102-0006.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:2:id:99-2020-RAE