Skip to Main content Skip to Navigation
Journal articles

Structure expansion of green coffee beans using instantaneous controlled pressure drop process

Abstract : Since 1988, when the first experiments with the Instantaneous Controlled Pressure Drop (DIC) process were performed, a lot of investigations have been carried out concerning the structure expansion, processing kinetics (drying, extraction and sterilization) and the improvement of the functional and organoleptic properties of fresh and dried foods. In this study, two DIC technologies were used to expand the structure of green coffee beans. Two varieties of commercial Arabica coffee beans of different agricultural and geographical origins (Brazilian and Ethiopian) were inspected. The effect of initial moisture content (7–40% dry basis), type of heating in the DIC process (steam and microwaves), processing parameters like pressure (0.4–0.7 MPa) and heating time (20–200 s) on bean expansion were investigated. The expansion was evaluated as the ratio of the tapped density of raw beans to that of the treated material. The hydration capacity of the beans was also studied. The Response Surface Methodology was employed to optimize the processing parameters. After the steam DIC treatment, the maximum expansion ratio of the Brazilian beans (e = 1.74) was higher than that of the Ethiopian beans (e = 1.59). For Brazilian beans, the steam DIC treatment resulted in a higher value of expansion ratio than the MW DIC treatment (e = 1.39). Concerning hydration capacity, the steam DIC treatment gave values of 78.6% and 48.2% d.b. for the Ethiopian and Brazilian beans, respectively. It means almost two-fold increase in the hydration capacity using DIC treatment. The steam DIC treatment increased and accelerated in twice the weight loss of beans during roasting.
Document type :
Journal articles
Complete list of metadata

Cited literature [17 references]  Display  Hide  Download
Contributor : Migration Prodinra Connect in order to contact the contributor
Submitted on : Sunday, May 31, 2020 - 8:03:22 AM
Last modification on : Thursday, October 21, 2021 - 4:12:48 AM


A4_Kristiawan IFST 2008_1.pdf
Files produced by the author(s)




Ibtisam M. Kamal, V. Sobolik, Magdalena Kristiawan, Sabah M. Mounir, K. Allaf. Structure expansion of green coffee beans using instantaneous controlled pressure drop process. Innovative Food Science and Emerging Technologies, Elsevier, 2008, 9 (4), pp.534-541. ⟨10.1016/j.ifset.2008.01.004⟩. ⟨hal-02666120⟩



Record views


Files downloads