Paper Title
Study of Whole Bamboo Shoots Drying Process Using Hot Air Oven Dryer and Solar Dryer
Abstract
The study of whole ‘Beechey’ bamboo shoots drying process by using hot air oven and solar dryer with a temperature at 60ºC found that in preliminary experiment, boiling the bamboo shoots in water with sodium meta-bisulfite 0.01% (w/v) for 30 minutes and saline 12% (w/v) of concentration for 30 minutes methods before drying could not inhibit the enzymatic browning reaction of dried bamboo shoots. Grilling whole bamboo shoots for 15 minutes before removing husk and covering them with salt for 5 days method could inhibit the enzymatic browning reaction but dried bamboo shoots quality decreased, since some area of bamboo shoots flesh was burnt. Boiling the bamboo shoots in water for 30 minutes before removed husk and covering them with salt for 5 days method showed the best result since the enzymatic browning reaction was better inhibited. Preparation whereby covering the bamboo shoots with salt could protect color deterioration. Especially, the time for covering with salt is increased, the enzymatic browning reaction was decreased in bamboo shoots but the drying time is increased and rehydrating rate is decreased. The study of time interval on covering the bamboo shoots with salt, which affected in color maintenance, before drying was done in 6 methods and all bamboo shoots were boiled and removed husk before covering with salt. In the first method, the bamboo shoots were uncovered with salt. They were used as a controlled group. The second to the last method, the bamboo shoots were covered with salt for 1 to 5 days, respectively. The result found that the drying using hot air and solar dryer with a temperature about 60ºC can reduce the moisture content of the bamboo shoots at 70–90% (w.b.) into 8–10% (w.b.) within 171–237 and 270–390 hours for hot air and solar dryer, respectively. In quality assessment of sensory using Hedonic scale method found that the bamboo shoots boiled in water for 30 minutes before removing husk and covering with salt for 2 days, which was dried by solar dryer show the highest score in quality and the next rank is the bamboo shoots boiled in water for 30 minutes before removing skin and covering with salt for 4 days, which was dried by hot air oven.
Keywords- bamboo shoots, drying, hot air dryer, solar dryer.