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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 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 EFFECT OF ENZYMATIC TREATMENT ON OIL RECOVERY USING MECHANICAL EXPRESSION FROM MUSTARD SEEDS(PAU Ludhiana, 2011) Pawanpreet Singh Grewal; A.K. SinghThe experiments were carried out with the objectives to determine various engineering characteristics and determining the operational parameters for better recovery of oil from two varieties of Mustard seed i.e. PBR-91 and RLC-1. The experiments were designed using response surface methodology for making various combinations of moisture content (6, 9, 12, 15 and 18%w.b.), heating time (2,4,6, 8 and 10 min), heating temperature (40,60,80,100 and 120°C) and enzyme concentration (1, 2, 3, 4 and 5%) and the experiments were conducted using single chamber oil expeller. The quality of oil was determined using acid number and peroxide value. The effect of independent variables i.e. moisture content, enzyme concentration and heating temperature on oil yield and residual oil in cake of PBR-91 and RLC-1 variety were found significant however the effect of the heating time was found non-significant in both the varieties. The highest amount of oil yield is 32.30% at 9% moisture, 4% moisture content, 60°C heating temperature and 8 minute heating time for PBR-91 and 32.09% for RLC-1 at 9% moisture content, 60°C heating temperature and 8 minute heating time. There is 8% increase in the yield of the oil for PBR-91 extracted at optimum level of parameters whereas in RLC-1 there is 8.89% increase in the oil yield compared to untreated seeds. Flow behaviour of oil was studied at different temperatures ( 10, 20, 30, 40 and 50°C) and different moisture level (6, 9, 12, 15 and 18%) at constant shear rate 15 S-1 showed decreasing trend of viscosity with increase in temperature.The flow behaviour of the samples were predicted by the values of consistency coefficient and flow behavoiur index. The range for consistency of oil was found to be 1.32 to 90.12 (PBR-91) and1.13 to 65.12 (RLC-1) for Power law model where as in Casson model it was 4.14 to 24.2 (PBR-91) and 3.12 to 17.3 (RLC-1). The flow behaviour index of PBR-91 ranged from -0.68 to0.94 whereas it varied from 0.18 to 0.96 for RLC-1 in Power law model . The range of yield stress was found to be 4.37 to 432 (PBR-91) and 2.1 to 400.1 (RLC-1) for Casson model.ThesisItem Restricted MULTI-LAYER DRYING OF GINGER (Zingiber officinale(PAU Ludhiana, 2011) Tarun Garg; Satish KumarInvestigations were carried out to study the effect of drying parameters on multi-layer drying of ginger. The drying parameters studied were moisture content, drying rate, temperature and relative humidity of outgoing air, product temperature and heat utilization factor. Quality attributes included rehydration ratio, coefficient of rehydration, shrinkage ratio, volatile oil content, colour. The multi layer drying was carried out at 60°C in Satake mechanical drier till an average moisture content of 5-6 % was achieved. The total drying time was between 5-16.5 hours. It was observed that moisture content, drying rate, relative humidity of outgoing air and heat utilization factor decreased with drying time but opposite trend was observed for temperature of outgoing air and product. The decrease in moisture content increased with increase in air velocities whereas opposite trend was observed for loading densities. Drying rate was higher for higher air velocity but opposite for loading density. A maximum heat utilization factor was observed for high loading density and low air velocity. Increase in air velocity resulted in decrease in heat utilization factor and relative humidity however temperature of outgoing air and product showed the opposite trend. Similar effect was observed for loading density. At air velocity 3.11 m/s the drying rate was maximum (8.45% db/min) for loading density 27.99 kg/m2 and heat utilization factor was maximum (1.00) for loading density 87.01 kg/m2. The rehydration ratio and coefficient of rehydration were maximum for sample having low loading density and air velocity but shrinkage ratio and volatile oil content were minimum for combinations having high loading density and low air velocity. There was a significant change in colour of fresh and rehydrated samples. The optimum conditions for multi-layer drying of ginger were observed to be 44.66 kg/m2 loading density and 3.5 m/s air velocity and corresponding values of rehydration ratio, coefficient of rehydration, shrinkage ratio, volatile oil and colour change were 4.98, 0.64, 1.87, 1.15 and 5.72 respectively.ThesisItem Restricted SPRAY DRYING OF TOMATO JUICE(PAU Ludhiana, 2011) Wungshim Zimik; Mahesh KumarA study was conducted to produce tomato powder using spray dryer (LSD-48) in the food engineering laboratory. The rheological parameters of fresh tomato juice and reconstituted juice were evaluated with the help of CVO-100 rheometer in engineering properties laboratory. A full factorial central composite rotatable design was used. The variable selected were air inlet temperature (140-160oC), feed flow rate (2.1-4.1 ml/min) and maltodextrin concentration (22.5-32.5%). The responses used in the analysis includes: recovery, lycopene content, solubility and ascorbic acid content. The air inlet temperature (145oC), feed flow rate (2.6 ml/min) and maltodextrin concentration (27.5%) were found to be optimum. Experiments were also performed to find out the total soluble solids, hue angle, chroma, titrable acidity, packed bulk density and moisture content. Results shows that with increase in air inlet temperature and feed flow rate, the moisture content, lycopene, packed bulk density, ascorbic acid, titrable acidity and solubility time decreased. Colorimetric analyses showed that the hue angle and chroma values changed with the inlet temperatures. The flow characteristics studies of the tomato juice and reconstituted juice of the optimized spray dried powder was undertaken at different processing temperatures. The flow behaviour of the samples were studied at different temperature levels from 40°C to 60°C at an interval of 5°C and shear rate range of 10 to 100 s-1 with 60.5oBrix total soluble solids. The flow behaviour of the samples was predicted by the values of consistency coefficient and flow behaviour index. The range for consistency coefficient of the fresh juice and reconstituted juice was found to be from 5.93 Pa sn to 20 Pa sn for Power law model and 1.47 Pa sn to 9.81 Pa sn for Herschel-Bulkley model. The flow behaviour index of fresh juice and reconstituted juice was found to be in the range of 0.70 to 0.89 for Power law and between 0.70 to 0.90 for Herschel-Bulkley model. Sensory evaluation and overall acceptability was also conducted for the fresh tomato juice and reconstituted juice on a 9-point hedonic scale.ThesisItem Open Access EFFECT OF PACKAGING MATERIAL AND STORAGE CONDITIONS ON SHELF LIFE AND QUALITY OF DRIED GINGER(PAU Ludhiana, 2011) Jasmeen Kaur; Satish Kumar, GuptaThe study on the effect of packaging material and storage conditions on shelf life of dried ginger was undertaken to select the suitable package material for extending the shelf-life of dried ginger based on physico-chemical quality and sensory evaluation. The ginger was peeled, cut and dried into three physical forms i.e. dried ginger flakes, dried rhizome and ginger powder and packaged in HDPE films, laminated aluminium films, PET containers and glass containers. These dried and packaged samples were stored under ambient conditions and refrigerated temperature (3+0.5°C). The analysis was carried out to estimate the quality and shelf-life of the stored dried ginger during whole storage period of four months. The parameters evaluated were colour change in terms of L value, chroma & hue angle, volatile oil (%), flavor (hedonic scale), shrinkage/swelling, weight change (g) and moisture content (% wb). Weight change (g) and moisture content (% wb) increased whereas colour change in terms of L value, chroma, lightness, flavour and volatile oil were decreased during storage period. Shrinkage/Swelling remained almost same during the storage period. Based on these physic-chemical quality parameters and sensory evaluation, it was found that the best physical form was powder followed by flakes and rhizome. Glass containers was the best packaging material followed by laminated aluminium films, HDPE films and PET containers for extending the shelf-life and maintaining the quality of dried ginger upto 4 months. Refrigerated conditions were observed as the better storage conditions than the room temperature. The statistical analysis was also done to check the significance of different packaging materials used under different storage conditions.ThesisItem Restricted STUDY ON ESSENTIAL OIL EXTRACTION OF SWEET BASIL (Ocimum basilicum)(PAU, 2013) Karanvir SinghThe present study was undertaken to find the kinetics of sweet basil oil extraction using steam and hydro distillation techniques, to access the quality of extracted oil and to optimize the process parameters for oil extraction. Sweet basil was procured from farms of Fieldfresh Foods Pvt. Ltd., VPO Ladhowal, Distt Ludhiana. The oil was extracted from fresh sweet basil leaves, shade dried sweet basil leaves and sun dried sweet basil leaves with moisture content 85.29%, 17.33% and 12.75% respectively. For extraction of oil from sweet Basil leaves at different moisture contents hydro distillation and steam distillation methods took 3-6 and 0.75- 1 hrs respectively. In case of hydro distillation method there is no oil recovery for each sample during first one hour and it started during second hour whereas in case of steam distillation method oil recovery started within 15 minutes. Maximum yield of 0.27% at 17.33% moisture content and minimum oil yield of 0.23% at 12.75% moisture content was observed in hydro distillation whereas in steam distillation method maximum yield of 0.62% at 85.29% moisture content and minimum yield of 0.16% at 12.75% moisture content was observed. The oil obtained from distillation methods was light yellowish to pale yellowish in color with very little greenish ting. Saponification value, acid value, specific gravity and refractive index were found to be 8.00, 1.90, 0.92 and 1.460 respectively. Sweet basil oil recovered was found to be insoluble in water. Steam distillation method was found to be the best method for oil extraction with maximum oil recovery and minimum time of extraction.