Template-Type: ReDIF-Article 1.0 Author-Name: R.K. Jha Author-Workplace-Name: Department of Agricultural and Food Engineering, Indian Institute of Technology, Kharagpur, India Author-Name: P.K. Prabhakar Author-Workplace-Name: Department of Agricultural and Food Engineering, Indian Institute of Technology, Kharagpur, India Author-Name: P.P. Srivastav Author-Workplace-Name: Department of Agricultural and Food Engineering, Indian Institute of Technology, Kharagpur, India Author-Name: V.V. Rao Author-Workplace-Name: Cryogenic Engineering Centre, Indian Institute of Technology, Kharagpur, India Title: Influence of temperature on vacuum drying characteristics, functional properties and micro structure of Aloe vera (Aloe barbadensis Miller) gel Abstract: Aloe vera possesses therapeutic, antioxidant and some other functional properties. These properties may be affected by processing operations. The present study investigated the influence of operating temperature on vacuum drying characteristics, functional properties and the inner solid structure of the fresh aloe vera gel. The gel was dried at a constant pressure of 720 mm Hg in the drying chamber at varying temperature of 30-60°C. The experimental data of moisture ratio of Aloe vera were used to fit different models and the effective moisture diffusion coefficients and activation energy were also calculated. The Page model was found to be the best fit to experimental data. The functional properties like water retention capacity, fat absorption capacity, and swelling of the dried product were studied and found to be decreased with increasing operating temperature. The damage to the inner solid structure was more pronounced at higher temperatures because of faster mass transfer through the pores of the solid. The best quality product was obtained when the temperature was maintained at 30°C. Keywords: therapeutic, moisture ratio, activation energy Journal: Research in Agricultural Engineering Pages: 141-149 Volume: 61 Issue: 4 Year: 2015 DOI: 10.17221/13/2014-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/13/2014-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201504-0001.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:4:id:13-2014-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Kaveh Author-Workplace-Name: Department of Biosystems Engineering, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran Author-Name: R. Amiri Chayjan Author-Workplace-Name: Department of Biosystems Engineering, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran Author-Name: M. Esna-Ashari Author-Workplace-Name: Departments of Horticultural Sciences, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran Title: Thermal and physical properties modelling of terebinth fruit (Pistacia atlantica L.) under solar drying Abstract: A laboratory solar dryer was used to study terebinth fruit drying. Two solar collectors were adjusted in east-west directions with the angle of 45°. Initial moisture content of terebinth fruit was dried under natural and forced airflow. In order to predict terebinth moisture content during drying process five mathematical models were used. Colour change and shrinkage of the terebinth samples were calculated. Results showed that the Page model had the best performance in moisture content prediction of terebinth samples. Effective moisture diffusivity of terebinth fruit was increased under forced convection. The lowest colour change and shrinkage of the samples in natural air flow condition were observed. Maximum rupture force and energy values were obtained at maximum airflow velocity. Models were fitted to the experimental data of physical, thermal and mechanical properties of terebinth fruit with high correlation coefficients. Keywords: thin layer, moisture diffusivity, shrinkage, colour, rupture energy Journal: Research in Agricultural Engineering Pages: 150-161 Volume: 61 Issue: 4 Year: 2015 DOI: 10.17221/45/2013-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/45/2013-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201504-0002.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:4:id:45-2013-RAE Template-Type: ReDIF-Article 1.0 Author-Name: O.B. Oduntan Author-Workplace-Name: Department of Aquaculture and Fisheries Management, Faculty of Agriculture & Foresty, University of Ibadan, Ibadan, Nigeria Author-Name: B.O. Omitoyin Author-Workplace-Name: Department of Aquaculture and Fisheries Management, Faculty of Agriculture & Foresty, University of Ibadan, Ibadan, Nigeria Title: Wear of disc mill hammer in wet grinding processes on groundnut cake for fish feed production Abstract: There is need to determine the wear rates of disc mill hammer used for grinding groundnut cake, a major plant protein in fish feed. This surface wear damage characterised by scoring, cutting, deep grooving and gouging on a metal surface leads to high costs of production. The hammer wear rate was carried out using disc mill for different combinations of processing conditions: disc speed of 2,175, 3,900 and 4,350 rpm; screen size of 1.0, 2.0 and 3.0 mm; moisture contents of 12, 14 and 16% w.b. at 300 operating hours. Response Surface Method was used to optimize the operating variables. The wear rate was found to increase as the moisture content of the groundnut cake decreased. Quadratic models developed for the four responses (tip length loss, width loss, thickness loss and absolute mass) studied indicated the optimum conditions at disc speed 3,262.50 rpm, screen size 2.0 mm and moisture content 14% w.b. The study established that experimental data and model predictions agreed well. Keywords: plant protein, processing conditions, metal surface, optimize, responses Journal: Research in Agricultural Engineering Pages: 162-169 Volume: 61 Issue: 4 Year: 2015 DOI: 10.17221/67/2013-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/67/2013-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201504-0003.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:4:id:67-2013-RAE Template-Type: ReDIF-Article 1.0 Author-Name: F.A. Ola Author-Workplace-Name: Department of Agricultural Engineering, Faculty of Engineering and Technology, Ladoke Akintola University of Technology, Ogbomoso, Nigeria Author-Name: S.O. Jekayinfa Author-Workplace-Name: Department of Agricultural Engineering, Faculty of Engineering and Technology, Ladoke Akintola University of Technology, Ogbomoso, Nigeria Title: Pyrolysis of sandbox (Hura crepitans) shell: Effect of pyrolysis parameters on biochar yield Abstract: Pyrolysis of sandbox shell was carried out with the aim of investigating the effect of pyrolysis parameters on the pyrolysis process and identifies production conditions for the yield of biochar. Parameters investigated were heating temperature (400, 500 and 600°C), heating time (10, 20, and 30 min) and particle size of feedstock (0-1.0, 1.0-2.5 and 2.5-5.0 mm) in a laboratory batch pyrolysis process. The experiment was designed by applying response surface methodology through a three-factor full factorial design. The quadratic polynomial model obtained explains adequately the modelled response with coefficient of correlation, R2 value of 0.8698. All the three variables significantly affected the biochar yield from sandbox shell, with heating temperature being the most effective followed by heating time and particle size of feedstock. Maximum biochar yield of 39.65% wt. occurred at 400°C heating temperature and 10 min heating time with 1.0-2.5 mm particle size. Keywords: residue, thermal, reactor, model, factorial Journal: Research in Agricultural Engineering Pages: 170-176 Volume: 61 Issue: 4 Year: 2015 DOI: 10.17221/69/2013-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/69/2013-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201504-0004.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:4:id:69-2013-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Müller Author-Workplace-Name: Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Influence of loading speed on a change of parameters of adhesive bonds based on cyanoacrylates Abstract: The paper deals with a behaviour of adhesive bonds created by means of quick-setting adhesives at different speeds of a loading. The aim of the research was to simulate a change of a bearing capacity of the adhesive bond at marginal limits foregoing the bond destruction. Application of quick-setting adhesives based on cyanoacrylates is considerably spread in a technical practice. Its advantage is speed of a hardening process. A fast creation of a bond and a possibility of fast manipulation with the adhesive bond are connected with it. The manipulation strength of the adhesive bond is reached in a few seconds. The aim of the research is to describe behaviour of quick-setting adhesives based on cyanoacrylates at different speeds of loading of the adhesive bonds in an interval of 1 to 600 mm/min. A change of the adhesive bond strength, an elongation and a failure time were evaluated within the experiments. Also the behaviour of the adhesive bonded material was observed within the research. Keywords: adhesive bond strength, adhesive bonding technology, elongation, time of destruction Journal: Research in Agricultural Engineering Pages: 177-182 Volume: 61 Issue: 4 Year: 2015 DOI: 10.17221/15/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/15/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201504-0005.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:4:id:15-2015-RAE