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  • ThesisItemOpen Access
    Development and evaluation of process protocol for vacuum fried carrot chips (Daucus Carota L)
    (Department of Processing and Food Engineering, KCAET, Tavanur, 2021) Babu, P; KAU; Rajesh, G K
    Carrots are highly nutritious vegetable, which can be consumed in raw and processed form throughout the world. Carrot plays a vital role in the development and protection of human body. Carrot contains vitamins viz., B1(Thiamine), B2(Riboflavin), B6(Niacin) and B12 (Cobalamin) besides rich in source of βcarotene and dietary fibre which are helpful to prevent cancer and other dreadful diseases occur in human body. In Kerala state, carrot production is very limited, but its consumption is more. The postharvest losses of carrot were estimated as 18- 20%. The development of value-added products from carrot was an idealistic solution to reduce the postharvest losses by adopting new processing technologies. At present, due to consumer’s awareness, there is a lot of demand for healthy and tasty snack products with less oil content which provide good health. In this context, investigation on processing technologies focus on producing high quality fried products with less oil content and good textural property. The technology of vacuum frying is a best option for the production of novel snacks which fulfil the consumers demand and meet nutritious requirements. Vacuum frying is a novel technology, in which the food is heated under lower temperature and pressure(<6kPa). Vacuum frying lowers the water activity, oil content, retains the color and preserve nutrients in the fried product. The batch type vacuum frying system consists of two chambers viz., frying chamber (3kg capacity) and oil storage chamber (30-35L capacity). The refined palm oil was used for vacuum frying and de-oiling was done at 1000 rpm for 10 min. After every batch of vacuum frying, the oil was collected for quality analysis. Prior to the research, the physico-chemical properties of raw carrot (Ooty-1) was determined. The pre-treatments viz., blanching, blanching cum drying, blanching cum freezing, freezing and gum coating were optimized based on the quality of vacuum fried carrot chips. The freezing pre-treatment obtained the best results among other pre-treatments in terms of less oil content (14.48 %), water activity (0.214), moisture content (2.67%), hardness (1.282 N) and red color retention of a* value (22.85). The standardization of process parameters were done using RSM (CCRD) based on the quality characteristics of VF-carrot chips. The process parameters seected in this study were frying temperature (100,110 and 1200C), frying pressure (11,13 and 15 kPa) and frying time (16,18 and 20 min). The optimum operating conditions of vacuum frying viz., frying temperature, vacuum pressure and frying time were found to be 100°C, 11 kPa and 16 min respectively. At optimum operating conditions of 100°C, 11 kPa and 16 min, the quality parameters were oil content (11.31%), bulk density(0.873 g/cm3 ), true density(1.714 g/cm3 ), moisture content(3.28%), water activity (0.384), hardness (1.31 N),thickness expansion (60.42%), L*(43.48), a*( 14.36) b*(28.12) and energy content(1021 KJ/100g). Packaging and storage studies were conducted for the treatments which had high sensory score. The laminated aluminium flexible pouch with N2 gas filling was found to be the best packaging technique to enhance the shelf life of VF carrot chips to a storage period of 4 months. The oil quality parameters viz., total polar compounds (TPC), viscosity, peroxide, free fatty acids (FFA) etc were within the allowable limits even after 40 batches of vacuum frying. The total production cost of 1kg of vacuum fried carrot chips was found to be Rs. 355/-.
  • ThesisItemOpen Access
    Investigations on high rate anaerobic bioreactor for energy production from rubber latex processing effluent
    (Department of Farm Machinery and Power Engineering, Kelappaji College of Agricultural Engineering and Technology,Tavanur, 2020) Megha, A S; KAU; Shaji James, P
    Agro-processing industries often contribute significantly in pollution due to discharge of untreated effluents. By anaerobic digestion of these organic effluents, methane rich gas can be produced which is suitable to generate electricity and process heat. But conventional biogas plants are slow in operation with long hydraulic retention times of 35 to 40 days which necessitates large digester volumes. So, anaerobic digestion of high volume agro-processing effluents is feasible only through high rate bioreactors which can reduce hydraulic retention time to few hours. Rubber latex processing effluent (RLPE) is a dilute waste water for which high rate anaerobic treatment can be an affordable technology. Hence, an investigation was taken up to study the performance of Up-flow Anaerobic Hybrid Bioreactor for energy conversion of rubber latex processing effluent (RLPE). Physico-chemical characteristics of RLPE samples were tested and found that RLPE was a dilute waste water with pH in the acidic range. BOD: COD ratio of 0.44 obtained in this study showed good biodegradability of RLPE. A batch anaerobic digestion study was conducted as a preliminary experiment to investigate the biomethanation characteristics of RLPE. The experiment consisted of four treatments having different composition of RLPE with inoculums replicated thrice. This study could prove that RLPE could be subjected to biomethanation and cow dung slurry can be used as inoculum. Even at a lower inoculum: substrate ratio of 1:2, the system could be started up yielding substantial amount of biogas coupled with good TS reduction. Performance of field scale Up-flow Anaerobic Hybrid Bioreactors (UAHBR) was assessed by operating them at different HRTs of 10, 7, 5, 3 and 2 day. During the study an interruption of 2 months in operation occurred due to shut down of the processing unit due to Covid 19. After interruption of 2 months reactor recovered within one month and it proved that hybrid bioreactor could be restarted easily after a shutdown for few months. Reactor was stable in operation during 10, 7, 5, 3 and 2 day HRTs and exhibited good process efficiency with better pollutant reduction and biogas production. Performance was seen deteriorated beyond 5 day HRT. The bioreactors were operated successively at reduced loading rates corresponding to the longer HRTs after reaching the shortest HRT of 2 day. It was observed that there was no considerable difference in daily biogas production with the earlier values obtained during the progressive decrease in HRT. This revealed that the bioreactors would have achieved the maximum possible microbial population already and there was no further improvement in performance on further passage of time. The performance parameters obtained in the investigations with field scale reactors were used for evolving guidelines to design a full scale anaerobic bioreactor. The UAHBR performance was quite satisfactory at 5 day HRT with respect to pollutant reduction as well as energy production. Hence as criteria, full scale plant was proposed to be operated at 5 day and the corresponding reactor volume was 27 m 3 with 7.2 m 3 gas holder volume. The biogas expected to be produced from the full scale plant can be used in a biogas fired rubber sheet dryer which can save about 500 kg of fire wood per day currently used for drying rubber sheets.
  • ThesisItemOpen Access
    Investigations on soil crop and machine parameters towards the development of a root crop harvester
    (Department of Farm Machinery and Power Engineering, Kelappaji College of Agricultural Engineering and Technology,Tavanur, 2020) Basavaraj; KAU; Jayan, P R
    The tractor drawn root harvester was designed and developed by considering soil, crop and machine parameters and performance evaluation of the machine was carried out in the experimental area at KCAET, Tavanur and different farmers’ fields at Palakkad and Thrissur districts. The developed machine mainly consists of main frame, power transmission system, digging and soil separator units. The effect of three blade geometries viz., straight edge, V-type and crescent blades at three rake angles of 15, 20 and 25 deg. and at three forward speeds of 1.5, 2.0 and 2.5 km h-1 for the digging unit of the harvester were evaluated in terms of draft, digging efficiency, per cent damage of tuber/rhizome and fuel consumption of tractor mounted harvester for harvesting coleus, ginger and turmeric. The best optimal condition was observed at a forward speed of 2.0 km h-1 with 20 deg. rake angle for V-type blade. The soil separator unit of the harvester was evaluated along the digging operation. The soil separator unit was tested with different operational parameters viz., diameter of crank 40, 60 and 80 mm and spring tension 800, 1200 and 1600 N m-1. The best optimal operational conditions were observed at a spring tension of 1600 N m-1 with 80 mm diameter of crank. The maximum draft of 2009.52 N was recorded in straight blade while the minimum of 1418.66 N was observed in V-type blade. The maximum digging efficiency of 99.89 per cent was noticed in V-type blade, whereas the lowest of 84.15 per cent in straight edge blade. The least damage coleus of 0.59 per cent was observed in V-type blade whereas highest of 5.5 per cent was obtained in crescent blade. Among the different type of blades tested, the less fuel consumption of 3.80 l h-1 was noticed for V-type blade, whereas the maximum of 4.98 l h-1 for straight edge blade. In the case of harvesting ginger, the maximum draft of 2176.33 N was recorded in straight edge blade while the minimum of 1374.31 N was observed in V- type blade. The maximum digging efficiency of 99.57 per cent was noticed in V-type blade, whereas the lowest of 80.40 per cent in straight edge blade. The least damage coleus of 0.86 per cent was observed in V-type blade whereas highest of 6.05 per cent was obtained in crescent blade. Among the different type of blades, the less fuel consumption of 3.74 l h-1 was noticed for V-type blade, whereas the maximum of 5.19 l h-1 for straight edge blade. In the case of harvesting of turmeric, the maximum draft of 2192.08 N was recorded in straight edge blade while the minimum of 1390.06 N was observed in V-type blade. The maximum digging efficiency of 99.50 per cent was noticed in V-type blade, whereas the lowest of 81.91 per cent was recorded with the straight edge blade. The least per cent damage coleus of 0.74 per cent was observed in V-type blade whereas highest of 7.3 per cent was obtained in crescent blade. Among the different type of blades, the less fuel consumption of 4.0 l h-1 was noticed for V- type blade, whereas the maximum of 5.57 l h-1 for straight edge blade. The field capacity of the machine for coleus, ginger and turmeric were 0.15, 0.16 and 0.16 ha h-1 respectively and the field efficiencies were 86.11, 88.89 and 88.89 per cent respectively. The soil separation indices of root crop harvester for coleus, ginger and turmeric were found out as 82.71, 73.22 and 68.82 per cent respectively where as the conveying efficiencies were 90.70, 87.55 and 89.71 per cent respectively. The estimated cost of the prototype tractor drawn root crop harvester was as Rs. 60,000. The cost of operation was found out as Rs. 767.57 per hour. The saving in cost over root crop harvester for three root crops was 89 per cent. The machine has BEP of 40 h, PBP as 1.5 years and BCR as 10.7.
  • ThesisItemOpen Access
    Development of automated drip fertigation system using GSM based controller
    (Kelappaji college of Agricultural Engineering and Technology, Tavanur, 2019) Akhila Shiney, P; KAU; Sajeena, S
    Lack of sufficient water to grow enough crops for meeting the food demand of the increasing population is the major threat to Indian agriculture. The surface irrigation techniques cause seepage losses, erosion and water logging problems, deep percolation, salinization and runoff. To get satisfactory growth, application of right quantity of water at right time and at right place is very important and this can be accomplished only through micro irrigation techniques. Through automated drip fertigation, we can easily attain the agriculture intensification. The present study was focused on the development of GSM based automated drip fertigation system. In this study, calibration of capacitance type soil moisture sensors were carried out in laboratory for different soil types viz. laterite soil, black soil and costal alluvium soil. Field study was carried out with an Ujwala (KAU) variety of chilli crop under three treatments such as 100 percent irrigation and 100 percent fertigation with automation (T1), 100 percent irrigation and 100 percent fertigation without automation (T2) and 100 percent irrigation and 70 percent fertigation with automation (T3). The automated drip fertigation system consists of four capacitor type sensors, electronic fertilizer injection pump and fertilizer mixing device. Total yield and crop growth parameters showed better performance under 100 percent irrigation and 100 percent fertigation with automation (T1). Combination of 100 percent irrigation and 70 percent fertigation with automation (T3) also gave the good result which was on par with T1. Therefore, it could be concluded that with 30 percent less fertilizer, better performance of crop was obtained with automated drip fertigation system. It could also be shown that the right quantity of water at right time at right place is giving better performance of crop. The developed automated drip fertigation system is cost effective, portable, can perform better in field.
  • ThesisItemOpen Access
    Development and evaluation of an automated pulse irrigation system
    (Department of Irrigation and Drainage Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2019) Prasang H Rank; KAU; Vishnu, B
    Irrigation sector consumes more than 80% of the fresh water resources in India. The irrigation efficiencies of the major irrigation systems in India are around 40%, increasing of which could save large amounts of water. The irrigation efficiencies could be increased through the adoption of cost-effective and efficient irrigation technologies, which will reduce water demands, increase agricultural production, minimize soil and water pollution and reduce the cost of agricultural production. Drip/Trickle irrigation is a highly efficient irrigation method which could save tremendous amounts of water when adopted in the place of the wild flooding irrigation. Pulse drip irrigation technology enables lower application rates - that will permit sufficient aeration in the root zone and alleviate plant stress due to inadequate root respiration– from an emitter with a higher application rate by intermittent water applications. This study attempted to develop and evaluate a sensor based automated pulse drip irrigation system which is affordable to the lowincome farmers of the nation. The soil properties of the experimental field were used to estimate the parameters of several soil water characteristics curve (SWCC) models. Among the models; van Genuchten (1980) model of SWCC, was found to be the best in representing the soil moisture retention characteristics of the soil used in the study. An open-source electronics platform, the Arduino was used for the development of the automation system using moisture content sensors and solenoid irrigation valves controlled through relays, by writing program coding in the Arduino programming language. The sensors were calibrated to read the moisture content, which was compared to the management allowed deficit (MAD) and field capacity (FC) soil moisture content values to control the start and stop of irrigation water application. Pulse irrigation design methodology was used to derive the ON and OFF time periods for the pulse cycle. The system was programmed to start the water application as per the designed pulse cycle at a moisture content defined by the MAD moisture content and to stop the water application at the field capacity (FC) moisture content sensed by the moisture sensor. The wetting front movements and the soil moisture contents in the root zone were measured at different time 182 intervals of 1 hour, 2 hours and 3 hours after the start of water application using both continuous irrigation and pulse drip irrigation under 2 LPH, 4 LPH and 8 LPH online drip emitters. The soil aeration was also determined for these treatments and was found to be better during the pulse irrigation as compared to the continuous drip irrigation. The pulse irrigation application was also found to be decreasing the deep percolation loss of water. The developed automated pulse drip irrigation system is found to provide the required aeration in the root zone with reduction in deep percolation loss of water.
  • ThesisItemOpen Access
    Runoff estimation of KCAET campus by curve number methods adopting remote sensing and GIS techniques
    (Department of Soil and Water Conservation Engineering , college of Agricultural Engineering and Technology, Tavanur, 2019) Anjana, S R; KAU; Jinu, A
    This study mainly focused to estimate the runoff of KCAET Campus using the curve number method. The study was carried out in GIS enviromuent using remote sensing data. Also the curve number method was validated for selected storm events in the study area. The analysis was done for tlie year 2004 to 2007, 2018 and 2019 upto June. The land use map was digitized from Google eartli of year 2006 and 2018. ArcGIS 10.2 was used for the analysis. About 28.5% of the total area belongs to high runoff potential class, 33.7% have medium mnoff potential and 37.7% of the area has low runoff potential. The runoff percentage from the annual rainfall varied from 16% to 23% for tlie study period. The runoff percentage in 2007 and 2018 were almost similar but the rainfall depths of both years were 3971.8 mm and 2919.8 mm respectively. The rainfall amount in the study area is showing a decreasing trend and runoff is showing increasing trend. Seasonal analysis showed that maximum rainfall deptli was observed in south west monsoon and thereby runoff yield. The runoff percentage was lower in the pre monsoon season as the major part of the rainfall will infiltrates into the soil. Also the runoff depth was highly influenced by antecedent moisture condition and potential maximum retention capacity. The curve number values for noimal conditions were 57.77 and 58.95 for the year 2006 and 2018 respectively. The cuiwe number value tends to increase as antecedent moisture condition increases. The simulated runoff was compared with observed runoff for selected storm events in the study area. The correlation coefficient was found to be 0.928. The integration of remote sensing and GIS along with NRCS curve number method was found to be a powerful tool in estimating runoff.
  • ThesisItemOpen Access
    Estimation of soil moisture indices using diffuse reflectance spectroscopy
    (Kelappaji college of Agricultural Engineering and Technology, Tavanur, 2019) Sarathjith, M C; KAU; Anu Varughese
    Rapid and reliable estimation of soil moisture constants namely, field capacity (FC) and wilting point (WP) is significant for scientific irrigation scheduling. The conventional methods for their estimation are cumbersome, time consuming and not suitable for their estimation at different space and time domains. An alternative would be the use of diffuse reflectance spectroscopy (DRS) for which the development of calibration functions that link the soil attributes with spectral signature is a major pre-requisite. In this study, the utility of spectral index, feature projection of full-spectrum and variable selection approaches namely, normalized difference reflectance index (NDRI), partial least squares regression (PLSR) and ordered predictor, selection (OPS), respectively to build accurate and less complex calibration functions was evaluated. The performance of calibration functions were judged in terms residual prediction deviation (RPD) criteria. The NDRI based calibration functions developed in this study do not comply witli the minimum accuracy level (RPD<1.4) expected from DRS analysis. In contrast, both full-spectrum based PLSR and OPS approaches yielded calibration functions which were capable for accurate (RPD>2.0) and moderate (1.42.0) estimation of FC and WP, respectively. Specifically, the full-spectrum based calibration function developed using second derivative of reflectance was found to be the best for both FC (RPD=2.01) and WP (RPD=1.74). The OPS approach in conjunction with variable indicators namely, combination of regression & correlation coefficient (/?- r) and combination of adjacency values of mutual information & signal-to-noise vector (AMl-StN) yielded best calibration functions in case of FC and WP, respectively. The calibration functions so developed consisted of only 19.09% (FC) and 34.39% (WP) of total number of spectral vaiiables as that in full-spectrum. Thus, the result of the study advocate the use of OPS approach to develop simple and parsimonious calibration functions to estimate FC and WP from spectral signature of soil.
  • ThesisItemOpen Access
    Evaluation and refinement of low cost automation system for naturally ventilated greenhouse
    (Department of Soil and Water Conservation Engineering, Tavanur, 2019) Jinu, A; KAU; Abdul Hakkim, V M
    Greenhouses are structures used for offseason cultivation of crops and also for obtaining maximum production from unit area. In greenhouses, crop growing environment as well as growing medium can be modified by adopting suitable technologies for microclimate control and water and fertilizer application. Manual controls of microclimate and water and fertilizer application are time and labour consuming and hence automation is required for the better greenhouse management. The study entitled “Evaluation and refinement of low cost automation system for naturally ventilated greenhouses” was conducted during the period July 2015 to February 2017 to modify the existing low cost automation system at ARS Anakkayam and also for its performance evaluation. Existing automation system has limitations such as it cannot manage temperature and relative humidity separately and also it cannot manage irrigation and fertigation. These problems were rectified in refined automation system. The refinement of the system was done by changing the microcontroller used in the automation system and also using a timer for the timely management of irrigation and fertigation. The refined system was capable of managing temperature and relative humidity separately and performing irrigation and fertigation operations inside the greenhouse. The refined automation system was tested without crop and with crop during three crop seasons with salad cucumber crop (variety Saniya) inside the greenhouse. The experiment was conducted inside a naturally ventilated greenhouse situated at the ARS, Anakkayam, under Kerala Agricultural University. For comparison, salad cucumber was cultivated inside another greenhouse which is manually controlled. Microclimate as well as crop data were collected from outside the greenhouse and both these greenhouses and compared. The temperature inside the AGH was less compared to NAGH and the relative humidity inside the automated greenhouse never exceeded above 70%. The yield and all other crop parameters were better in AGH compared to NAGH.
  • ThesisItemOpen Access
    Studies on pulsed electric field assisted extraction of anthocyanin from jamun
    (Department of Processing and Food Engineering, Tavanur, 2019) Akhila, J Chand; KAU; Prince, M V
    Colour is considered as one of the major quality parameter of food. Anthocyanins are water soluble pigments after chlorophylls and impart red to blue colours to various fruits, vegetables and storage organs. Jamun is one of the under processed minor fruit found commonly in different parts of Indian continent. It is a rich source of anthocyanin. Conventional methods of extraction of anthocyanin is less productive and the extracted product is inferior in quality. In this study pulsed electric field assisted extraction was carried out with an objective of increasing the yield and quality parameter. A pulsed electric field system was developed to carry out pretreatment prior to extraction. The developed system consists of an outer protective chamber, inlet unit, pulse generating system, treatment chamber, display unit and cooling system. Pulse generating system consists of a Line Output Transformer, micro controller and filter unit. The treatment chamber consists of electrodes and isolated feedback circuit. In order to evaluate the developed system towards extraction of anthocyanin from Jamun, the process variables such as electric field strengths of 5, 10, 15kV/cm, pulse frequencies of 60, 80 and 100 pulses/s and treatment time of 2, 3 and 4 minutes were selected and the results were compared with conventional extraction. The results were then analysed statistically for optimization of the process parameters. The optimized conditions of electric field strength, pulse frequency and treatment time were found to be 9.47 kV/cm, 60 pulses/s and 2.24 minutes. The quality parameters of PEF assisted extracted anthocyanin such as anthocyanin yield, antioxidant activity, colour values and refractive index were 11.9mg/100 of sample, 97.2%, L value of 2.1, a* value of 2.36, b* value of -2.23 and 1.38 respectively whereas, the same for conventional extraction process were 10mg/100g of sample, 82.3%, L value of 3.1, a* value of 1.23, b* value of -1.35 and 1.37. It was concluded from the study that PEF assisted extraction resulted in higher anthocyanin yield and increased quality characteristics compared to conventional extraction process.