Volume:2, Issue:2 - 2020

Design, Fabrication and Evaluation of Solar and Biomass Hybrid Dryer with Trackable Solar Collector

2020-12-01T00:00:00Z

Design, Fabrication and Evaluation of Solar and Biomass Hybrid Dryer with Trackable Solar Collector Kumarasiriwardhana, C.A.; Kahandage, P.D.; Weerasooriya, G.V.T.V. Newly constructed solar and biomass hybrid dryer consists of solar collector with solar tracking option, biomass backup heater and a drying chamber. The absorber of the trackable solar collector was made of black painted corrugated GI sheet and clear glass for the top. Saw dust was used as the fuel for the biomass burner. The drying chamber was built of plywood and insulated by aluminium foil. The performance was evaluated using five drying treatments with three replicates; namely, only with solar power (T1), solar power with tracking (T2), only with biomass (T3), with hybrid mode (T4), and direct sun drying (T5; Control). Invented hybrid dryer reduced the initial moisture content of Musa spp. (banana), Artocarpus heterophyllus (jackfruit) and Pleurotus ostreatus (oyster mushroom) from 80%, 74% and 90% to 12%, 12% and 10%, respectively. Under no-load condition, the average temperature of drying chamber reached to 45.04 0C with solar drying and 55.65 0C with solar tracking option, while the ambient temperature was 33.52 0C. The solar collector efficiency obtained from the no-load test was 34.07%. Results revealed that the dryer can reduce the high initial moisture contents up to a safe storage moisture content within a day. With the support of the backup heater, the dryer can be used even under the inadequate solar radiation. Improper drying chamber insulation was observed as a limitation.

Design, Fabrication and Evaluation of a Hand-Operated Semi-Automatic Chopping Machine for Leafy Vegetables and Medicinal Herbs

2020-12-01T00:00:00Z

Design, Fabrication and Evaluation of a Hand-Operated Semi-Automatic Chopping Machine for Leafy Vegetables and Medicinal Herbs Kahandage, P.D.; Darmasena, D.A.N.; Kosgollegedara, E.J. A hand-operated semi-automatic vegetable chopping machine was designed, fabricated and evaluated to introduce an efficient chopping machine to ease the preparation of leafy vegetables and herbal medicines. The main features and components of the chopping machine were integrated cutting and feeding mechanism, operating handle, cylindrical container, piston, collecting drawer and the frame. The machine was designed to operate manually reducing the operational & capital cost and to ease the use in rural areas, where there is no electrical supply. A performance test was done for this machine using four different leafy vegetables and medicinal herbs [Mukunuwenna (Alternanthera sessilis), Kankun (Ipomoea aquatica), Gotu kola (Centella asiatica) and Kathuru murunga (Sesbania grandiflora)] in comparison with manual chopping using a general kitchen knife. Five unskilled males and females were involved in a performance test with three replicates. The three-factor factorial experimental design was used in the evaluation. The actual capacity and the efficiency of the chopping machine were 1.81 kg h-1 and 74%, respectively compared to 1.02 kg h-1 and 76% of the manual kitchen knife. The average width of a particle cut by machine and kitchen knife were 1.87 mm and 3.38 mm, respectively. According to the user-feedback, this machine is a safe, affordable and convenient device for processing vegetables and herbal medicines.

Quality and Price Variation in the Dairy Value Chian: A Case Study in Monaragala District, Sri Lanka

2020-12-01T00:00:00Z

Quality and Price Variation in the Dairy Value Chian: A Case Study in Monaragala District, Sri Lanka Wickrama, P.S.S.L.; Sandika, A.L.; Jayamanne, V.S. Low value addition, quality and price variations have been recognized as common problems of value chains in developing countries. Objective of the present study was to examine the quality and price variations throughout the dairy value chain in a less developed region in Sri Lanka. Wellawaya divisional secretariat of Monaragala district was purposively selected as the study area. Primary data were collected by using pre-tested, structured questionnaires. Laboratory tests of milk and curd samples were carried out to check the quality variation using standard methods. Milk samples were collected from three levels including farmer (10), processor (10 from each, milk and curd) and retailer (10) to determine the quality variation. According to the results, price of curd and yoghurt at consumer level was increased by 36% and 77% compared to the farm gate price. Farmer received the highest profit per liter of milk (68.00 LKR) in the shortest value chain (D) out of four main chains identified. The markets’ margin was estimated at 36%. Farmer had the largest share of 64% followed by processor (20%), retailer (8%), collector (4%), and wholesaler (4%). It was evident that farmers received fair profit through all four dairy value chains. However, solid non-fat percentage, specific gravity and pH of analyzed samples through the value chain were not comply with the standards. In conclusion, the prices of dairy products have increased while deteriorating the quality along the chain. It is therefore important to educate and train actors throughout the dairy value chain on quality management.

Effect of Protease Supplementation on Growth Performances, Carcass and Meat Quality Characteristics of Broiler Chicken Fed with Low Protein Diets

2020-12-01T00:00:00Z

Effect of Protease Supplementation on Growth Performances, Carcass and Meat Quality Characteristics of Broiler Chicken Fed with Low Protein Diets Sumanasekara, T.D.I.M.; Nayananjalie, W.A.D.; Ang, L.; Kumari, M.A.A.P. The effect of feeding low dietary crude protein (CP) with different levels of supplemental protease enzyme on commercial broilers was investigated. Three hundred broiler chicks were divided into five treatments with six replicates in a completely randomized design. The experimental diets were positive control (recommended CP levels, T1), negative control (level of CP reduced by 5%, T2), negative control + 300 g t -1 protease (T3), negative control + 400 g t -1 protease (T4) and negative control + 500 g t -1 protease (T5). Growth, blood serum, carcass quality and meat quality parameters were measured. Data were analysed using one-way Analysis of Variance. The highest live weight (2.86 ± 0.07 kg), weight gain (2.66 ± 0.05 kg) and the lowest feed conversion ratio (1.84 ± 0.06) were observed in birds fed with T5. There was no influence of treatments (p>0.05) on NH3 emission from litter, dressing percentage, meat quality and blood serum parameters. The feed cost per producing 1 kg of live weight and sellable carcass weight was significantly low (p<0.05) in T5. Thus, it can be concluded that low protein diets supplemented with protease enzyme at 500 g t -1 support better growth performances in broiler chicken with a lower cost of production.