Template-Type: ReDIF-Article 1.0 Author-Name: Adolf Rybka Author-Name: Petr Heřmánek Author-Workplace-Name: Department of Agricultural Machines, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: Ivo Honzík Author-Workplace-Name: Department of Agricultural Machines, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Effect of drying temperature in hop dryer on hop quality Abstract: One of the qualitative characteristics of both green and dried hops is the content of hop essential oils which are contained in a quantity of 0.5 to 3.5%, depending on the hop variety. These essential oils are heat labile substances because the temperature has an influence on their content. Hop cones, dried either in belt or chamber dryers, are exposed to a drying medium temperature of 55 °C to 60 °C for the entire duration of drying, i.e. for 6-8 hours. Under current drying conditions there is a loss of approx. 15 to 25% of the total content of essential oils present in hops before drying. In case of special aroma hop varieties, such losses lead to a decline in the product quality. Comparative measurements have been carried out with a laboratory equipment to find out whether more aromatic essential oils are retained in hop cones at a drying temperature of 40 °C compared to a drying temperature of 60 °C. The measurement carried out with the most common variety of Saaz hop concluded that the essential oil losses were lower by 33.4% at a drying temperature of 40 °C, and with other seven mostly hybrid varieties the losses were lower on average by 13.9% than at a drying temperature of 60 °C. The measurements proved that each of the varieties retained, to a significant extent, its content of essential oils in the dried hop cones at a drying temperature of 40 °C. Keywords: hop cones, hop drying, laboratory dryer, quality of hops Journal: Research in Agricultural Engineering Pages: 1-7 Volume: 67 Issue: 1 Year: 2021 DOI: 10.17221/61/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/61/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202101-0001.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:1:id:61-2020-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Abiodun Okunola Author-Workplace-Name: Department of Agricultural and Biosystems Engineering, College of Engineering, Landmark University, Omu-Aran, Nigeria Author-Name: Timothy Adekanye Author-Name: Endurance Idahosa Author-Workplace-Name: Department of Agricultural and Biosystems Engineering, College of Engineering, Landmark University, Omu-Aran, Nigeria Title: Energy and exergy analyses of okra drying process in a forced convection cabinet dryer Abstract: A forced convection automatic cabinet dryer integrated with a data logger was designed and fabricated. The okra samples were dried in the dryer at drying temperatures of 50, 60, and 70 °C and at three different load densities of 200, 300, and 400 g at a continuous air velocity of 0.7 m.s-1. Energy and exergy analyses of the drying process were performed. The obtained results showed that the energy efficiency, energy utilisation, and utilisation ratio increased from 26.59 to 68.24%, 5.47 to 114.36 W, and 0.36 to 0.71 as the temperature increased to 70 °C, respectively. The inflow, outflow, and exergy losses were in the range of 7.02 to 26.14 W, 4.43 to 14.16 W, and 2.59 to 11.98 W, respectively, while exergy efficiency varied from 49.15 to 63.47%. The findings show that exergy efficiencies decrease with an increase in the drying temperature, but increase with a lower load rate. The index of sustainability varies from 2.14 to 2.77, the value increases as the load density decreases while it decreases with a temperature increment. Keywords: agriculture, food processing, force drying, tray dryer Journal: Research in Agricultural Engineering Pages: 8-16 Volume: 67 Issue: 1 Year: 2021 DOI: 10.17221/48/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/48/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202101-0002.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:1:id:48-2020-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Mahmood Reza Salar Author-Workplace-Name: Department of Biosystem Engineering, Faculty of Agriculture, Shiraz University, Shiraz, Iran Author-Name: Seyed Hossein Karparvarfard Author-Workplace-Name: Department of Biosystem Engineering, Faculty of Agriculture, Shiraz University, Shiraz, Iran Author-Name: Mohammad Askari Author-Workplace-Name: Department of Biosystem Engineering, Faculty of Agricultural Engineering, Sari Agricultural Sciences and Natural Resources University, Sari, Iran Author-Name: Hoda Kargarpour Author-Workplace-Name: Department of Biosystem Engineering, Tarbiat Modares University, Tehran, Iran Title: Forces and loosening characteristics of a new winged chisel plough Abstract: This study was devoted to verifying the performance of various configurations of a winged chisel plough (WCP) in a soil bin. The performance of the new tool was assessed at three wing depths (5, 10 and 15 cm), three bend angles (10, 20 and 30 °), and three rake angles (7.5, 15 and 22.5 °) with three replications using a completely randomised design at a constant depth and speed of 30 cm and 1 m.s-1, respectively. The draught and vertical forces, soil disturbed and upheaved areas plus the efficiency of the soil loosening were measured during the tests. The results revealed that the draught and vertical forces were significantly increased by increasing the wing depth, bend and rake angles. The soil disturbance area increased with an increase in the wing depth, bend and rake angles. While the soil upheaving was decreased by increasing the wing depth and bend angle, the effect of the rake angle on the soil upheaving area was not significant. The maximum efficiency of the soil loosening of 268.1 cm2.kN-1 was achieved for a wing depth of 10 cm, a bend angle of 20 °, and a rake angle of 15 °. A significant improvement in the efficiency of the soil loosening along with maintaining a considerable portion of the residue on the soil surface suggest that the WCP should be adopted for conservation tillage. Keywords: bend angle, draught force, loosening efficiency, wing, rake angle Journal: Research in Agricultural Engineering Pages: 17-25 Volume: 67 Issue: 1 Year: 2021 DOI: 10.17221/71/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/71/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202101-0003.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:1:id:71-2020-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Olajide Ayodele Sadiku Author-Name: David Omogunsoye Author-Workplace-Name: Department of Agronomy, Faculty of Agriculture, University of Ibadan, Ibadan, Oyo State, Nigeria Title: Moisture - Influenced friction properties of ackee apple (Blighia sapida) seeds Abstract: The friction properties of ackee apple (Blighia sapida) seeds at an 11.9, 17, 22, 27, and 32% (w.b.) seed moisture were determined, which are vital for designing their processing techniques and equipment to replace the present manual methods. The ackee apple grows in many West African countries, especially Nigeria. The ackee seeds were harvested at Lanlate, Oyo State, Nigeria, where ackee trees are predominant. Standard experimental methods were adopted to determine the properties. The data were analysed using an ANOVA and the least significant difference (LSD) at P ≤ 0.05. As the moisture increased, the static coefficient of friction on glass (27.6-36.40), aluminium (27.0-30.2), polyvinyl chloride (PVC; 27.9-32.8) surfaces and normal stress at 200 g (8.73-8.93 g×cm-2), 300 g (11.65-11.79 g×cm-2) and 400 g (14.37-14.65) loads increased significantly and linearly. The shear stress linearly decreased at a 200 g load (1.62-1.25 g×cm-2), but was non-significant at the 300 and 400 g loads. The coefficient of internal friction linearly decreased (0.744-0.588) implying that the wet seeds flow more easily than the dry ones, which should be considered in designing conveyors. The relationships between the ackee seeds' moisture and friction properties were expressed with regression models. Data for designing the handling techniques and machines for the ackee seeds were obtained. Keywords: machine, technique, data, processing, shear stress Journal: Research in Agricultural Engineering Pages: 26-33 Volume: 67 Issue: 1 Year: 2021 DOI: 10.17221/75/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/75/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202101-0004.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:1:id:75-2020-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Olawale Ogunnigbo Author-Workplace-Name: Department of Mechanical Engineering, Faculty of Technology, Obafemi Awolowo University, Ile-Ife, Nigeria Author-Name: Dare Adetan Author-Workplace-Name: Department of Mechanical Engineering, Faculty of Technology, Obafemi Awolowo University, Ile-Ife, Nigeria Author-Name: Tunde Morakinyo Author-Workplace-Name: Department of Food Science Engineering, Faculty of Technology, Obafemi Awolowo University, Ile-Ife, Nigeria Author-Name: Olusola Olusunmade Author-Workplace-Name: Department of Mechanical Engineering, College of Engineering, University of Agriculture, Makurdi, Nigeria Author-Name: Bolaji Ojerinde Author-Workplace-Name: Department of Mechanical Engineering, Faculty of Technology, Obafemi Awolowo University, Ile-Ife, Nigeria Title: A study on the influence of the loading rate and orientation on some mechanical properties of cassava tubers of different ages Abstract: The study determined the effects of the speed of loading and the loading orientation on some selected mechanical properties of the TME 419 cassava tuber variety at different ages of the tuber which are essential in the design and construction of the processing and handling equipment of a cassava peeler. The properties considered include the bioyield and rupture points, compressive and rupture strengths, toughness and firmness, and moduli of stiffness and toughness, which were carried out in the transverse and longitudinal loading direction using an Instron Universal Testing Machine (UTM). As the loading rate increased from 5.00 to10.00 mm.min-1 and the age of the tuber varies from 1.00 to 2.00 years, the bioyield and rupture points, compressive and rupture strengths, toughness, firmness, moduli of stiffness and toughness in the transverse and longitudinal direction varies from 1 619.61 to 3 636.19 N and 136.08 to 384.52 N, 0.48066 to 1.07913 N.mm-2 and 0.26604 to 0.75173 N.mm-2, 766 to 1055 N.mm-1 and 1 262 to 2 965 N.mm-1, 303.98 to 553.68 mm.min-1 and 28.08 to 53.71 mm.min-1 2.30 to 4.19 N.mm-2 and 5.376 to 8.94N.mm-2 respectively. Generally, the values of the properties examined are higher in the longitudinal loading orientation than in the transverse and for a year and half old tuber which will be useful in designing an efficient cassava peeling system. Keywords: compressive strength, transverse loading, longitudinal loading, loading speed, toughness Journal: Research in Agricultural Engineering Pages: 34-44 Volume: 67 Issue: 1 Year: 2021 DOI: 10.17221/57/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/57/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202101-0005.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:1:id:57-2020-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Inemesit Edem Ekop Author-Workplace-Name: Department of Agricultural Engineering, Faculty of Engineering, Akwa Ibom State University, Ikot Akpaden, Uyo, Nigeria Author-Name: Kayode Joshua Simonyan Author-Workplace-Name: Department of Agricultural and Bioresources Engineering, College of Engineering and Engineering Technology, Michael Okpara University of Agriculture, Umudike, Nigeria Author-Name: Udochukwu Nelson Onwuka Author-Workplace-Name: Department of Agricultural and Bioresources Engineering, College of Engineering and Engineering Technology, Michael Okpara University of Agriculture, Umudike, Nigeria Title: Comparative analysis of the physical properties of two varieties of periwinkle relevant to the design of processing equipment Abstract: The physical properties of agricultural products are essential in designing machines, equipment, and systems for efficient processing operations. Two periwinkle varieties, viz Tympanotonus fuscatus (Linnaeus, 1758) and Pachymelania aurita O. F. Müller, 1774, were utilised in this study to investigate and determine their physical properties relevant to the design of efficient processing equipment. The geometric (axial dimensions, mean diameters, surface area, sphericity, aspect ratio) and gravimetric (bulk and true densities, mass, and porosity) properties were measured. The averages for the major diameter, arithmetic mean diameter, geometrical mean diameter, and surface area were highest in the T. fuscatus variety. In contrast, the minor diameter, sphericity, and aspect ratio were highest in the P. aurita variety. The average bulk and true densities, porosity, and average periwinkle weight for T. fuscatus were higher than the P. aurita variety. Tukey's pairwise comparison analysis carried out on all the physical properties of the T. fuscatus, and P. aurita varieties of the periwinkle shells revealed a statistically significant difference at P < 5%. Keywords: periwinkle varieties, T. fuscatus, P. aurita, geometric properties, gravimetric properties Journal: Research in Agricultural Engineering Pages: 45-50 Volume: 67 Issue: 1 Year: 2021 DOI: 10.17221/58/2020-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/58/2020-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-202101-0006.txt Handle: RePEc:caa:jnlrae:v:67:y:2021:i:1:id:58-2020-RAE