Physical Characteristics of Coffee Beans from Steaming Processin Single Column Reactor

Main Article Content

Sukrisno Widyotomo
Sri Mulato
Hadi K. Purwadaria
A.M. Syarief


One of important steps in decaffeination process is steaming. The aim of steaming is to expand coffee beans porosity in order to obtain optimal condition for decaffeination process. Steaming can be done in single column reactor using saturated water vapour as media. The objective of this research is to study physical characteristics of coffee beans after steaming process using single column reactor. Material tested was Robusta coffee with 13—14% moisture content after dry processing. Reactor capacity is 6 kg dried coffee beans and 30 l water to produce water vapour. Dried coffee beans classified in 4 grades, i.e. diameter size (d) d>7,5 mm; 6,5<d³7,5 mm; 5,5<d£6,5 mm; and d£5,5 mm. Period of steaming process varied from 1 up to 3.5 hours. The result showed that the coffee beans expanded 8.6—9.5% in length, 12.2—13.3% in width, and 18.3—20.6% in thickness. Coffee bean volume increased 30—50%. Coffee bean moisture content increased f. Aritmatic diameter increased 8—13% while geometric diameter increased 9—18%. Sphericity not affected. Surface area increased 18—37%. True density increased 19—30% while bulk density was while. Porosity increased from 13—18% to 24—39% while coffee beans texture decreased from 323—384 g/1 mm to 212—225 g/1 mm. Color change increased from 14—20 to 38—40. The optimum steaming process was 3 hours.Key words : Coffee, steaming, single column reactor, decaffeination.

Article Details

How to Cite
Widyotomo, S., Mulato, S., K. Purwadaria, H., & Syarief, A. (2010). Physical Characteristics of Coffee Beans from Steaming Processin Single Column Reactor. Pelita Perkebunan (a Coffee and Cocoa Research Journal), 26(1).
Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Authors who publish with this journal agree to the following terms:

    1. Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
    1. Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
    1. Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).


Most read articles by the same author(s)