| Author | Bui Boi Hai |
| Call Number | AIT Thesis no. AE-95-18 |
| Subject(s) | Food--Drying
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of
Engineering, School of Environment, Resources, and Development |
| Publisher | Asian Institute of Technology |
| Abstract | In this study, a spouted vortex-bed dryer was designed, constructed and tested for its
performance for a variety of liquid foods. The overall drying setup was modified from an
existing spray-drying unit. Teflon pellets were used to form the bed of inert material. The
surface of the moving pellets was wetted by the liquid feed and dried by the hot air
simultaneously.
The dried material was subsequently peeled off from the surface of pellets due to
vigorous agitation and collected in the form of tiny flakes in a cyclone separator.
The continuous agitation of pellets in drying chamber required the use of higher air
velocities which resulted in high pressure drops. The mass of pellets present in drying
chamber directly influenced the pellets movement, available contact surface area, and drying
capacity. Other parameters affecting the dryer performance induded the inlet and outlet
temperatures of hot air and liquid feed rate. It appeared that vortex-bed dryer could be used
economically for the small-scale operation.
The experimental vortex-bed dryer showed a good general performance in drying of
different kinds of liquid foods varying in solid content from 1 % (pedal leave extract) to
47.85% (egg yolks). Detailed results on drying of tomato juice indicated that both inlet and
outlet hot air temperatures affected the quality of final product in terms of the moisture
content and color index. The optimum values of inlet and outlet temperatures for drying of
tomato juice in the experimental vortex-bed dryer were determined to be 107 and 81 °C based
on the best color of the dried powder. |
| Year | 1995 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Jindal, V. K. |
| Examination Committee(s) | Athapol Noomhorm;Vincent, J. C.;Rakshit, S. K.
|
| Scholarship Donor(s) | Government of Norway
|
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1995 |