Studies of the fluidised bed drying of cherries in relation to the post-harvest handling of coffee in Viet Nam | |
| Author | Pham Tri Thong |
| Call Number | AIT Thesis no. AE-97-13 |
| Subject(s) | Crops--Postharvest technology--Vietnam Coffee--Vietnam |
| 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 | The on-farm postharvest handling systems and their effects on the Robusta coffee quality are studied in Viet Nam. This study estimates the postharvest losses occurring in the actual postharvest practices of Robusta coffee berry in Southern Viet Nam. Results of the experiments indicate that the quantitative losses expressing in terms of national and farming economic aspects are hundreds and tens of millions of dollars; respectively. Since the Robusta coffee crop in Viet Nam produces more and more, large quantities are not able to be dried by traditional methods; i.e. sun drying or natural drying, and the quality of Viet Nam Robusta coffee has not been evaluated as a nice cup of coffee yet due to traditional farming habits. To minimize losses, appropriate postharvest practices, specially fluidised bed drying of Robusta coffee, must be developed. Drying characteristics of Robusta cherry with fluidised bed dryer are determined at four levels of drying air temperatures 60, 70, 80, and 90°C. Changes of moisture content with drying time are fitted using two models, simple logarithmic and Page's model. Relationships between the drying parameters kl, k2 and n in these models with time are also determined through regression. The value of kl varies from 0.2580 to 0.7286. The value of k2 varies from 0.4205 to 0.8695 and n from 0.6716 to 0.7916. The increase of drying parameters with temperature increasing is reasonable. Linear relationship between kl, k2 and n with temperature increasing is reasonable. Results show that the modified log model yields close agreement between experimental and predicted moisture content profiles. Iris concluded that ll f the parameters concerning in fluidised bed drying-- of Robusta cherry could be determined. Results also indicate that there is no effect of drying air temperature on caffeine content of Robusta coffee and on color index of raw and roasted Robusta bean. The results of organoleptic tests are non significant difference among the drying air temperature due to applying high temperature and so far much more experimental cup tests should be carried out further. |
| Year | 1997 |
| 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) | Vincent, Jean Claude ;Athapol Noomhorm; |
| Examination Committee(s) | Jindal, Vined K.; |
| Scholarship Donor(s) | Ecumenical Scholarships Programme, Germany (Bread For The World) ; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1997 |