Loading...
Thesis
Browse
7 results
Search Results
ThesisItem Restricted Performance evaluation of double layered polyethylene greenhouse solar dryer for drying of selected horticultural produce(Punjab Agricultural University, Ludhiana, 2017) Pinki; Mahesh KumarThe present study was conducted with an objective to evaluate the performance of double layered greenhouse solar dryer for drying of horticultural crops cabbage, spinach, onion and carrot that uses solar energy. Greenhouse solar dryer used was of 10×6 square ft area with polyethylene layering over trays. Exhaust fan was used at speed of 2.08 m/sec for forced convection. The performance evaluation of greenhouse solar dryer was done for drying of cabbage, spinach, onion, carrot and compared with open sun drying, single layer natural convection solar drying, double layer natural convection solar drying, single layer forced convection solar drying, double layer forced convection solar drying. All the four crops cabbage, spinach, onion and carrot were given physical treatment i.e. cutting; drying kinetics of all the crops chosen was studied by open sun drying, single layer natural convection solar drying, double layer natural convection solar drying, single layer forced convection solar drying, double layer forced convection solar drying techniques. The quality parameters included colour, ascorbic acid, polyphenol content, shrinkage ratio, rehydration ratio and overall acceptability. Double layer solar drying under forced convection took the minimum drying time i.e. 480, 275, 585, 385 min for cabbage, spinach, onion, carrot respectively followed by double layer solar drying under natural convection i.e. 785, 495, 665, 885 min for cabbage, spinach, onion, carrot respectively; accompanied by final moisture content 6-7% (db) for all crops. The quality of double layer solar drying under forced convection found comparable with open sun drying.ThesisItem Restricted Design, development and performance evaluation of solar assisted mechanical tray dryer for chillies(Punjab Agricultural University, Ludhiana, 2017) Arora, Sakshi; Mittal, T.C.The present study was conducted with an objective to design and develop a solar assisted mechanical tray dryer to dry red chillies that uses solar energy during sunshine hours and backup energy during non-sunshine hours to dry the product continuously. The developed dryer consists of 20 tube (1800 mm long)- evacuated tube type solar collector, 4 U-type finned electrical heaters (1kW) and an AC motor (1HP) and blower assembly to provide the required air flow rate. The performance evaluation of designed dryer was done for drying red chilli (CH-27) and compared with sun drying, improved sun drying and mechanical drying. Chillies were given physical pretreatment i.e. chopping; drying kinetics of whole and chopped chillies were studied at 2.5, 5 and 7.5 kg/m2 loading density by sun drying, improved sun drying and mechanical drying technique. The quality parameters included colour, ascorbic acid, capsaicin and colouring matter. Solar assisted mechanical dryer took the minimum time i.e. 54.5 hours to dry whole chillies at 7.5kg/m2 loading density followed by mechanical drying (62 hours), sun drying and improved sun drying both of which took nearly 15 days; accompanied by the lowest final moisture content for both whole (5.20 ± 3.47%) and chopped samples (3.97 ± 1.13%). The quality of the product dried using the developed dryer was found comparable to mechanical drying. 33.69 ± 1.36% saving in energy consumption was observed when solar + electrical mode of designed dryer was used as compared to only electrical heater mode.ThesisItem Open Access Engineering characterization of kinnow and tomato for grading using image processing(Punjab Agricultural University, Ludhiana, 2017) Sandhya; Mahesh KumarThe present study was undertaken for characterization of kinnow and tomato based on engineering parameters using digital image processing. The images of kinnow and tomato of different grades were acquired using a digital camera. An algorithm using MATLAB was developed to quantify and process these digital images. The geometric parameters such as axial dimensions, mass, volume, density, sphericity, aspect ratio and ellipsoid ratio were recorded. The size of kinnow varied between 62.50-87.41 mm while tomato had size varying from 30.00-77.62 mm. Results of image analysis showed variation of major axis length from 1597.21 pixels to 1987.1 pixels for kinnow. The bulk density was found to be maximum (0.40 g/cc) for kinnow having size 72-74mm whereas it was highest (0.26 g/cc) for tomato of size 57-66mm. The sphericity varied in the range of 0.92-0.94 for kinnow while tomatoes of variety Punjab Chhuhara were found to be oblong. The results obtained by digital image analysis were compared and verified with the experimental observation recorded by vernier caliper. The volume computed from the images of longitudinal view and lateral view of kinnow and tomato of all the grades showed good correlation with the true volume measured by water displacement method. The Bland-Altman approach was used to plot the agreement between the values measured by both the methods and differences between two methods were normally distributed and were estimated to lie between M - 1.96SD and M + 1.96SD, known as 95% limits of agreement. The paired samples t-test results showed that parameters determined with image processing method was not significantly (P>0.05) different from the same parameters measured with vernier caliper. A linear relationship between mass of the kinnow and tomato and the projected area, volume and axial dimensions was also developed for prediction of mass using image processing.ThesisItem Open Access Ultrasound assisted aqueous enzymatic extraction of maize (Zea Mays L.) germ oil(Punjab Agricultural University, Ludhiana, 2017) Datt, Samridh; Sidhu, Gagandeep KaurIn the present study ultrasound assisted aqueous enzymatic extraction of maize germ was carried out. A three-variable, three-level response surface methodology using Box–Behnken design (BBD) was applied for optimizing the extraction condition in order to obtain the high oil recovery from the maize germ. The three independent variables set were extraction temperature (40-60°C), ultrasonic pre-treatment time (40-60) min, and water to seed ratio (4:1-6:1w/w) at the three levels. A total of seventeen experiments were designed. By considering all the responses simultaneously for optimization, it was found that the optimum conditions for extraction of maize germ using UAAE method was found as incubation temperature of 40°C, time 60 min and water to seed ratio of 4.86:1 respectively. The maximum oil recovery under these was found as 86.20%. The optimized samples had a saponification value of 189.27 (mg KOH/g), acid value 3.15 (mg KOH/g), FFA 1.58 (mg KOH/g), peroxide value of 5.01 (millieq), density 883.55 (kg/m3), color change 20.08, refractive index of 1.50 respectively and total extraction time was 7.5 h and it was taken as the basis for the comparison with solvent extraction method. It was found that oil recovery from solvent extraction was nearly same as that of UAAE but the quality parameters of the UAAE extracted oil was better than that of solvent extracted oil. The oil extracted by the optimized parameters of UAAE oil and the oil extracted by the solvent extraction method were subjected to storage in the glass and HDPE bottles in dark and light under ambient conditions. There was considerable change in the quality parameters in the solvent extracted oil and UAAE oil was quite stable even after the 90 days of storage. The extraction method was also subjected to economic analysis, it was clear that an initial investment of `2479360, the project gives profit of `370685 and payback period of 0.30 years and can provide employment to 2-3 persons.ThesisItem Open Access Fabrication of ventilated structure for storage of onion(Punjab Agricultural University, Ludhiana, 2017) Nancydeep Kaur; Mahesh KumarOnion is an important crop of the country that is consume throughout the year. Recently due to greater economic return associated with this crop, the farmers in our state have also paid enough attention for the cultivation of this crop. Looking at the physiology of this crop there is a lack of proper storage structure for keeping the bulb for such a long time so the present study was undertaken to develop suitable storage structure. As storage life of the onions is linked with its harvesting at proper stage followed by thorough curing. Properly harvested onion crop at vegetable farm of PAU was field cured. It was also cured in shade as well as in mechanical drier. Using this information a ventilated onion storage structure of capacity 1.25 tonn was fabricated. The results indicated that the highest losses (22.55 %) were recorded when the onion cured at the open field for 5 days, followed by shade curing treatment (18.08 %) for 9 days and the lowest losses were 15.8 % for the artificial curing treatment at the end of storage period. Physical characteristics of onions i.e. average size, angle of repose and bulk density was calculated as 32.75-68.67 mm, 26⁰ and 560 kg/mᶟ respectively. Ventilated storage structure was (size 1.2m х 1.2m х 1.5m) made up of angle iron frame and MS 1 inch square mesh. For ease of loading and unloading the onion, an inclined surface at the base with angle of repose 26 degrees has been provided. Three axial flow fans at the base of ventilated storage structure created variable air flow rate with air velocities of 0.27 m/s, 0.32 m/s, 0.69 m/s, 0.9 m/s and 1.38 m/s. Onions in bulk were filled in the structure and samples of 10 kg of 5 onion bags were kept at different location within the structure and at different air velocities for this study. The variations in vital parameters were compared with commercially cold stored onions in cold stores (0 to -1⁰C). It was observed that PLW, sprouting, TSS, colour difference, moisture content, hardness, ascorbic acid and reducing sugars during 3 months of storage varied significantly at CD 5% level of significance. This study indicates that onions which were stored at air speed 1.38 m/s and cold stored showed minimum loss and maximum retention of chemical properties. But due to high rent of cold stored onions, cold storage is not normally preferable in India.ThesisItem Open Access Development and evaluation of percussion based machine for quality management of stored grains and their milled products(Punjab Agricultural University, Ludhiana, 2017) Jindal, Shilpa; Alam, M.S.The study was carried out to develop a machine for non-chemical disinfestation of stored grains and milled products. The machine was designed on the principle of physical disturbance to control the insect-pests of grains /milled products. The developed machine was evaluated for grains (wheat and bengal gram) and their milled products (wheat flour, maida and besan). The developed machine process parameters i.e. Operational speed (OS) (500-1500 rpm for grains and 2000-2800 rpm for milled products) and Number of passes (NOP) (1-3) were optimized using response surface methodology (RSM). Optimization was done aiming at minimum broken % and maximum mortality percentage for grains while the goal for milled products was maximum mortality % with minimum change in size, moisture content and colour. The optimized machine process parameters obtained for disinfestation of wheat grains and bengal gram were 1300 rpm and 1450 rpm OS with one pass respectively. For milled products, the optimized machine parameters obtained were 2800 rpm, 2650 rpm OS with single pass for wheat flour and besan respectively whereas, for maida two pass with 2600 rpm OS was adjudged to be the best. In order to evaluate the efficacy of physical treatment, storage period and packaging material, the samples developed at optimized condition were stored in different packaging material (Steel, PET containers and PP bags) under ambient condition and were monitored for change in quality attributes at 15 days interval. Treatment followed by storage days and packaging material significantly affected (p<0.05) the quality attributes (moisture content, colour change, insect incidence, insect infestation and overall acceptability) of the samples. Machine treated samples showed no change in quality attributes in comparison to untreated sample irrespective of the selected commodity. The samples packed in steel containers were adjudged to be the best in retaining quality of stored product at the end of three months. Overall the developed machine was found to be highly effective in controlling the stored grains and milled product insect-pests.ThesisItem Open Access Effect of Aloe vera gel coating on shelf life and quality attributes of kinnow (Citrus deliciosa Ten.)(Punjab Agricultural University, Ludhiana, 2017) Surpreet Kaur; Gupta, Satish KumarKinnow is the major citrus fruit grown in Punjab and being perishable in nature, it cannot be stored for long periods at ambient conditions. In the present study, the impact of Aloe vera gel coating on quality attributes and shelf life of kinnow was assessed. Four concentrations of Aloe vera gel and water i.e. (0:1), (1:0), (1:1), (2:1) and (3:1) with standard amount of chitosan, pectin and glycerol (1% w/v) were utilized. Kinnow were stored at ambient and refrigerated conditions with LDPE packaging and without packaging. Physio-chemical characteristics- firmness, physiological weight loss, colour, TSS, titrable acidity, ascorbic acid content, TSS/acid ratio, juice content were assessed at an interim of 7 days during storage. The firmness, titrable acidity, ascorbic acid, juice content were gradually decreased more in case of untreated kinnow against the Aloe vera gel coated kinnow during storage. The physiological weight loss, colour change, TSS, TSS/acid ratio were increased during storage under ambient and refrigerated conditions however this increase was more in untreated kinnow when contrasted with treated kinnow. It was concluded that LDPE packed and coated kinnow had better quality and enhance shelf life up to 77 days against the unpacked and untreated kinnow which had 56 days of storage period under refrigerated conditions while in case of ambient storage, LDPE packed and treated kinnow had 10 days of storage while unpacked and untreated kinnow had just 6 days of storage life. It was inferred that Aloe vera gel coating could serve as an alternative option to lessen the post-harvest quality losses and enhance the shelf life of kinnow.