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ThesisItem Open Access Drying Kinetics And Storage Behaviour Of Black Soybean(G.B.Pant University Of Agriculture And Technology Pantnagar : Uttaranchal, 2005) Kumar,Kaushal.; Gupta,D.K.ThesisItem Open Access Drying characteristics and quality changes during tray and fluidized bed drying of carrot shreds(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2009-08) Keshri, Satish Kumar; Kulshreshtha, ManojA study on drying characteristics and quality changes during tray and fluidized bed drying of carrot shreds was under taken. Experiments were conducted to study the drying kinetics of carrot shreds, to compare the predictive models and to evaluate the quality, and b-carotene loss during tray and fluidized bed drying. Tray drying experiments were conducted under unblanched and blanched conditions, with and without turning at 50, 60 and 700C, and loading density of 1.5, 3.0 and 4.5 kg/m2. Fluidized bed drying experiments were carried out in unblanched and blanched conditions at 50, 60 and 700C with a sample size of 100, 200 and 300g at velocities of 2.22 and 1.81 m/s that corresponded to full and half opening of flap. Quality was studied in terms of moisture content, bulk density, true density, porosity, rehydration ratio, rehydration fraction, color and b-carotene content. In both tray and fluidized bed drying, Page’s model performed best in describing the drying behavior, while the Power law model did not fit the drying data. Drying took place under falling rate and there was no constant drying period. Analysis of variance indicated that in case of tray drying loading density had most significant effect on overall drying rate followed by turning, and temperature. In case of fluidized bed drying; only sample size and temperature had significant effect. Blanching did not have a significant effect on the drying rate in any case. Drying rate was 3-4 times higher in fluidized bed drying than in tray drying. In case of tray drying, turning had a significant effect on drying rate while flap opening did not have a significant effect on drying rate. Total drying time in tray drying ranged from 2-12h, while it was 0.5-2.5h in fluidized bed drying indicating a substantial saving of time in fluidized bed drying compared to tray drying. Physical characteristics (bulk density, true density, porosity) of dried shreds were similar in tray and fluidized bed drying. Rehydration ratio was higher for blanched sample, dried at lower temperature in both tray and fluidized bed drying. Rehydration ratio and rehydration fraction were slightly higher in fluidized bed drying. Blanching and temperature had a significant effect on quality of dried products. b-carotene was more in blanched samples dried at lower temperature in both cases. There was no significant difference on b-carotene and color in fluidized bed dried shreds and tray dried shreds. Overall there is no significant advantage in fluidized bed drying over tray drying in terms of quality of dried shreds.ThesisItem Open Access Hot air drying characteristics of sweet potato (Ipomoea batatas L.) cubes, its modeling using artificial neural network (Ann) and quality changes during storage of dried product(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2009-06) Singh, Ngankham Joykumar; Pandey, R.K.Sweet potato (Ipomoea batatas L.), rich in carbohydrate and other protective nutrients like vitamin A, carotene, calcium and phosphorus and contains small quantity of fat, protein, riboflavin, niacin and vitamin C etc, is an important tuber crop which is widely used in ready-to-eat foods, etc. Sweet potatoes have a very poor shelf-life and undergo spoilage due to deterioration of vascular and parenchymal tissues due to formation of blue vascular streaks. Hot air-drying characteristics of sweet potato cubes were investigated in a laboratory scale hot air dryer. The thin-layer drying was carried out under five air temperatures 50, 60, 70, 80 and 90oC, five air velocities of 1.5, 2.5, 3.5, 4.5 and 5.5 m/s and three sweet potato cube sizes of 5, 8 and 12 mm. Empirical models namely page’s, generalized exponential and logarithmic were fitted to drying data of moisture ratio. The model was selected on the basis of maximum R2 and standard deviation (SD). Page’s model gave better prediction for moisture ratio. Artificial Neural Network model was fitted in drying data. ANN modeling was done at two hidden layer (1 and 2) and ten neurons (2, 4, 6, 8 and 10). The optimum architecture of ANN for training at different drying characteristics such as moisture content, drying rate and moisture ratio was found to be two hidden layers with 8 and 4 nodes in first and second hidden layer, 2 nodes in first and 8 in second layer and 2 in hidden layer and 4 nodes in second layer, respectively. Hardness, Springiness, cohesiveness and resilience decreased slightly with increase in temperature and increased with increase in cube thickness; however adhesiveness and gumminess increased slightly with drying temperature. Based on quality attributes, the optimum conditions recommended for drying of sweet potato were 70oC drying air temperature, 5.5 m/s air velocity and 0.5 cm cube size. Dried sweet potato cubes could be stored in sealed polythene package for more than six months without much deterioration in its quality. Vacuum packaging resulted in better quality of stored sweet potato cubes as compared to the normal packaging method.