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ThesisItem Open Access Design, development and performance evaluation of LHAassisted hybrid solar dryer for onion (Allium Cepa L.)(Punjab Agricultural University, Ludhiana, 2018) Attkan, Arun Kumar; Alam, M.S.The study was conducted to design, develop and evaluate LHA-assisted hybrid solar drying system. The 3D-CAD model of the hybrid dryer was designed and prepared in NX-8 CAD drawing software on the basis of design calculations. Experiments were conducted to test the developed low humidity air (LHA) system for its regeneration capacity using silica gel for regeneration temperature (60-100ºC), air velocity (3-5 m/s) and loading weight (1-3 kg) using three factors, three levels Box-Behnken design. The optimized regeneration process parameters obtained were 100°C regeneration temperature, 4.77 m/s air velocity and 1.73 kg loading weight resulting in 0.255 kg/hr of regeneration rate, 160 minutes regeneration time, 0.83 kWh power consumed by blower and 0.75 kWh power consumed by heater. In order to evaluate the developed dryer, drying experiments were conducted on onion slices by varying the drying air temperatures (50, 60 and 70°C), KMS pre-treatment (0.1, 0.3 and 0.5%) and loading weight (10, 20 and 30 kg). RSM was employed for optimizing the drying process parameters of onion slices for the developed hybrid solar dryer and found the optimized drying process parameters were 64.98°C drying air temperature, 10 kg loading weight and 0.5% KMS pre-treatment resulting in maximum pyruvate content, rehydration ratio, color L-value, overall acceptability and minimum drying time, color change and power consumed by blower and heater. Mathematical model was developed by writing the heat and mass balance equations for developed dryer. Eight thin layer drying models (Newton, Page, Modified Page, Exponential, Asympotic, Two-term exponential Wang and Singh and Logistic) were fitted to mass transfer data and their adequacy of fit was investigated. Page equation accurately describes the drying behavior of onion slices Six EMC models (Modified Exponential, Modified Halsey, Modified Oswin, Modified Chung-Pfost, Guggenheim-Andersonde Boer (GAB) and BET) were fitted to the EMC data to investigate the sorption behavior of onion slices. Modified exponential equation was found superior for explaining the sorption behavior of onion slices with in the selected temperature and relative humidity range. A computer program was written in VISUAL BASIC language to develop the model. The developed computer model showed close agreement between the measured and predicted values and was quite effective in predicting the drying behavior of treated onion slices with average % error of 9.31, 11.43% and 2.93% for moisture content, moisture ratio and product temperature respectively. The cost economics of the developed hybrid solar dryer was evaluated on the basis of benefit cost ratio (Rs. 1.49), breakeven point (101.96 kg) and payback period (0.092 year) of dried onion powder at selling price of Rs. 400/- per unit respectively. Overall, the developed hybrid solar dryer was found quite energy efficient, economically viable and capable in maintaining the quality of dried onion slices.ThesisItem Open Access Development and Evaluation of Refraction Based System for Dehydration of Potato(Punjab Agricultural University, Ludhiana, 2018) Zalpouri, Ruchika; Preetinder KaurThe present study was conducted to develop and evaluate a refraction based system for dehydration of potato. Refraction based drying system was developed in Pilot plant, Department of Processing and Food Engineering, Punjab Agricultural University. The potatoes were peeled, cut into quarters, hot water blanched and immersed in 0.2% KMS solution for 15 min. After pretreatment, the potatoes were processed into puree and a known amount of distilled water was added to the puree to achieve desired TSS levels. The potato puree was dried by different drying methods viz. convective tray drying and refraction based drying system. The drying experiments were carried out at different TSS (8, 10 and 12º Brix), different blanching time (3, 4 and 5min) and at varying drying temperature 50, 60 and 70°C in convective tray drying and 70, 80 and 90oC in the refraction based drying system. It was observed that the physical properties of potato flakes were significantly affected by blanching time (p< 0.05). The moisture content ranged from 6.16-1.57% (db) and 7.61-3.46% (db) of potato flakes dried in refraction based drying system and convective tray dryer. Color values varied significantly (p<0.05) with respect to the drying method. Response Surface Methodology was used for optimization of process parameters. For refraction based drying system, the optimum operating conditions for drying temperature, blanching time and TSS were 70.00°C, 5.00 min and 11.54°Brix. At optimum condition, the values of responses were as follows protein content (31.66 mg/g), starch content (144.04 mg/g), reducing sugars (0.75 mg/g) and total sugars (6.25 mg/g) of dried potato flakes. For convective tray drying, optimum operating conditions for drying temperature, blanching time and TSS were 50.00°C, 4.23 min and 12.00°Brix. At optimum condition, the values of responses were as follows protein content (19.40 mg/g), starch content (16.47 mg/g), reducing sugars (0.94 mg/g) and total sugars (6.41 mg/g) of dried potato flakes. After considering all the parameters, it was found that refraction based drying system was more efficient as compared to the convective tray dryer.ThesisItem Open Access Development and evaluation of energy efficient tunnel dryer for chilli(Punjab Agricultural University, Ludhiana, 2018) Harmanpreet Kaur; Sharma, S.R.The study was conducted to develop and evaluate an energy efficient solar tunnel dryer. The dryer had dimensions of 12 X 8 X 4 m made of galvanized steel pipes and covered with 200µ thick polyethylene sheet having anti-mist and anti-drip properties. Three turbine fans were installed at the roof top of the dryer to provide natural ventilation. The performance evaluation of developed dryer was done for drying red chillies (CH-27). The maximum temperature recorded inside the dryer was 78°C which was 60.2 % higher than the corresponding ambient air temperature of 47°C. The corresponding relative humidity was 9.6 % against ambient air relative humidity of 21 %. The drying behaviour of pretreated red chillies was studied and colour of dried chilli was measured. The final moisture content ranged from 2.07% (d.b.) to 8.54% (d.b). In solar tunnel drying technique, the maximum drying time was found to be 31 sunshine hours for control whole chillies against 45 sunshine hours in open sun drying whereas the minimum drying time was found to be 12 sunshine hours for chemically treated chopped chillies against 15 sunshine hours in open sun drying. Also quality of chilli powder after grinding dried chillies was determined in terms of colour, colouring matter, capsaicin content and oleoresin content. Solar tunnel drying technique was much better than open sun drying technique in terms of drying behaviour and quality parameters. Solar tunnel dryer was found to be economical with pay-back period of 2.5 months and cost-benefit ratio greater than 1.ThesisItem Restricted Modeling and optimization of extrusion process for utilization of vegetable waste(Punjab Agricultural University, Ludhiana, 2018) Choudhary, Kanupriya; Alam, M.S.Investigations were carried out to determine the best blanching pre-treatment and drying method for the development of dried radish leaves and pea pods (vegetable waste; VW) powder. The experiments were conducted using completely randomized design (CRD) by varying the blanching pre-treatments viz. hot water (HB), potassium metabisulphate (KMS), citric acid (CB) and drying methods viz. sun drying , solar drying and convective drying ( 55, 65 and 75°C). All the results were statistically analysed to estimate the significant difference between blanching pre-treatments and drying methods on the basis of physico-chemical quality attributes namely drying time, equilibrium moisture content, amino acid content, lignin content, crude fibre, color change and overall acceptability. The best quality dried vegetable waste powder was utilized in development of vegetable waste incorporated soy-cereal based product. Rice based extruded product were developed by replacing the base material (rice) with vegetable waste (VW)-soy powder (SP) mixed in equal proportion. The vegetable waste i.e. Radish leaves and pea pods powder mixed in equal proportion. Response surface methodology (RSM) was employed for optimization of extrusion process using four factor, three level Box-Behnken design. The extrusion process parameters i.e. VW-SP proportion (%), feed moisture content (% wb), die temperature (°C) and screw speed (rpm) for rice based extrudates were optimized for the responses namely bulk density (BD), specific mechanical energy (SME), expansion ratio (ER), water absorption index (WAI), water solubility index (WSI), protein content (PC), crude fibre (CF), hardness (H), color change (CC) and overall acceptability (OA). In addition to the optimization of extrusion process the modeling of extrusion process variables by using RSM and genetic algorithms (GAs) was done. The developed models were fitted to the extrusion data and their adequacy of fit was investigated. The hot water blanched radish leaves, convectively dried at 65°C was found to be best for utilization in the extruded product. The untreated samples (UT) of pea pods dried convectively at 75°C was found to be best for utilization in the extruded product. For rice based extrudates the optimum values of process parameters obtained by using RSM were: 35% VW-SP (i.e. 65% rice proportion) with 13.17% feed moisture content, 152.29°C die temperature and 360.42 rpm screw speed. Results obtained from RSM and GA were comparable. The vegetable waste and defatted soy flour can be successfully incorporated @ 35% i.e. 17.5% vegetable waste i.e. 8.75% radish leaves powder, 8.75% pea pods powder and 17.5% defatted soy flour powder.ThesisItem Open Access Development of pectin-based bio nanocomposite films for food packaging(Punjab Agricultural University, Ludhiana, 2018) Nitin Kumar; Preetinder KaurThe present study was carried out to extract pectin from kinnow fruit peels and to assess its potential application in fabrication of pectin-based bio nanocomposite films. Pectin was extracted with nitric and citric acid and the effect of extraction time (30 to 60 min), temperature (60 to 80°C) and pH (1.5 to 2.5) was investigated on various physico-chemical properties of extracted pectin. The values of pectin yield, degree of esterification, intrinsic viscosity and molecular weight were higher in citric acid extraction of pectin as compared to nitric acid extraction. The extracted pectin and magnesium hydroxide nanoparticles were mixed with glycerol to develop bio nanocomposite films. The effect of pH (7 to 10) of the mix and sonication levels (20 to 100%) was significant on various film properties. At optimised levels of pH (9.80) and sonication (98.45%), the corresponding values of thickness, area, moisture absorption, tensile strength, elongation at break, water vapour transmission rate and gas transmission rate were 0.028 mm, 444.95 cm2, 5.51%, 4.44 MPa, 42.95%, 65.11 g m-2day-1 and 19.72 cm3 mm m-2day-1atm-1 respectively. The developed bio nanocomposite films had melting point of 7.38°C and glass transition temperature (-17.4°C). The film completely degraded in soil (25% M.C) 110 days and exhibited antimicrobial properties (inhibition zone = 7.89 mm) against E coli. The developed films were then compared with commonly used polymers (low density polyethylene and polypropylene) by packaging fresh cherry tomatoes (CV ) and storing under ambient (30°C, 61% RH) and low temperature storage conditions (10°C, 90% RH). The type of packaging material and storage conditions affected the physico-chemical parameters of the packaged produce viz. PLW, firmness, lycopene content, TSS and titratable acidity. The total cost of pectin-based bio nanocomposite films was estimated as Rs. 1075 per kg.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.