Changes Of Some Engineering Properties Of Coffee Beans Due To Roasting Process

Ashri Indriati, Dadang D Hidayat, Cecep E Andriansyah, Ari Rahayuningtyas, Arie Sudaryanto


The changes in physical, mechanical, and colours after roasting in two-level were investigated. Aims of this study were to evaluate changes in the physical, mechanical, and colours due to the roasting process of the Arabica and Robusta coffee bean grown in Cisalak Sub-District, Subang District-West Java. Results of analysis determined that the roasting process resulted in decreasing the moisture content of green coffee bean from 13.8% to 6,54% of first-level roasted bean and 6.24 of the second-level roasted bean, while that of robusta decreased from  11.22% to 7.56 and 6.12%. First-level roasting was categorised as a light roast, while the second-level was a medium roast. The Roast Weight Loss of arabica and robusta from green to light roast bean were 19.45 % and 16,24%, respectively, and that to medium roast bean was 26.20% and 22.37%, respectively. The roast volume change of arabica and robusta from green to light roast bean were 50.55% and 44.30 % respectively, and that to medium roast bean were 54.65% and 55.92 % respectively. The total colour differences between green with light and medium roast bean of arabica were 6.39 and 2.52, while that of robusta were 6.19 and 2.49, respectively.


Coffee Beans; Roasting Process; Engineering Properties; Coffee Beans Process

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The World Bank, Agro-Industry Proffles: Coffee, Report FAU-14 (The World Bank), Washingto DC, 1985.

Mohammed sani A A, “Physical Quality Analysis of Roasted Arabica Coffee Beans Subjected to Different Harvesting and Postharvest Processing Methods in Eastern Ethiopia” Journal of Food Science and Quality Management, Vol.57, 2016.

Kah Yau Ee, Jian Zhao, Ata-Ur Rehman Samson Agboola, “Effects of roasting on the characteristics of Australian wattle (Acacia Victoriae Bentham) seed and extracts” International Journal of Food Properties vol. 16, No. 5, pp.1135– 1147, 2013.

Ola Lasekan, Alfi Khatib, Kassim A Abbas, “Volatile compounds of roasted and steamed Malaysian tropical almond nut (Terminalia catappa L.)”, International Journal of Food Properties, Vol. 15, No. 5, pp.1120–1132, 2012.

Joanna Oracz, Ewa Nebesny, “Antioxidant properties of cocoa beans (Theobroma cacao l.): influence of cultivar and roasting conditions” International Journal of Food Properties, Vol. 19, No. 6, pp.1242-1258, 2016.

Sievetz, Desrosier, Coffee Technology. Westport: AVI Publishing Company.In Niya Wang. 2012. Physicochemical Changes of Coffee Beans During Roasting, (The University of Guelph) Canada, 1979.

Anna G Fiore, Carla Severini, Roberto Romaniello, Giorgio Peri, “Study of Physical Properties of Coffee Beans during Roasting. Application of Hyperspectral Image Analysis”, In 21st International Conference on Coffee ScienceAt: Montpellier (France), 2016.

Niya Wang, Physicochemical Changes of Coffee Beans During Roasting (The University of Guelph), Canada, 2012.

J Vosloo, Heat and mass transfer model for a coffee roasting process (the North-West University), Afrika, 2017.

Cameron Kelly, The Art of Coffee Roasting, Investigations into Sensor Development for the Application of Controlling Coffee Roasting, (The University of Waikato) New Zealand, 2018.

Jokanović R Marija, Džinić R Natalija, Biljana Cvetkovic, Grujic Slavica, Odžaković Božana, “Changes of physical properties of coffee beans during roasting”, Acta Periodica Technologica, Vol. 43, pp. 21-31, 2012.

A Illy, R Viani, Espresso Coffee, Second Edition: The Science of Quality (Academic Press), Amerika, 2005.

J A Hernándeza, B.Heyd, C Irles, Valdovinos, G Trystram, “Analysis of the heat and mass transfer during coffee batch roasting”, Journal of Food Engineering, Vol. 78,No. 4, pp.1141-1148, 2007.

A M Fareez Edzuan, A M Noor Aliah, H L Bong, “Physical and Chemical Property Changes of Coffee Beans during Roasting”, American Journal of Chemistry, Vol. 5, No. 3, pp.56-60, 2015.

E R Dutra, L S Oliveira, A S Franca, V P Ferrez, R J Afonso, “A preliminary study on the feasibility of using the composition of coffee roasting exhaust gas for the determination of the degree of roast”, Journal of Food Engineering, Vol. 47, pp.241–246, 2001.

P Pittia, M C Nicoli, G Sacchetti, “Effect of moisture and water activity on textural properties of row And roasted coffee beans”, Journal of Texture Studies, Vol. 38, pp.116-134, 2007.

Verônica Belchior, What Happens During Coffee Roasting: The Physical Changes, In Online available on physical-changes/ Accessed on 9/16/2019, 2019.

W, Burubai, A J Akor, A H Igoni, Y T Puyate, “Effects of temperature and moisture content on the strength properties of African nutmeg (Monodora myristica)”, International Agrophysics, Vol. 21, pp.217–223, 2007.

N N Mohsenin, Physical properties of plant and animal materials, (Gordon and Breach Publishers) New York, 1986.

A A Mohammedsani, “Physical Quality Analysis of Roasted Arabica Coffee Beans Subjected to Different Harvesting and Postharvest Processing Methods in Eastern Ethiopia”, Food Science and Quality Management, Vol.57, 2016.

V Chandrasekar, R Viswanathan, “Physical and thermal properties of coffee”, Journal of Agricultural Engineering Research, Vol. 73, pp.227-234, 1999.

Bart-Plange A, Edward A. Baryeh, “The physical properties of Category B cocoa beans”, Journal of Food Engineering, Vol. 60, pp.219–227, 2003.

K K Singh, T K Goswami, “Physical properties of cumin seed”, Journal of Agricultural Engineering Research, Vol. 64, pp.93-98, 1996.

S H Suthar, S K Das, “Some physical properties of karinga seeds”, Journal of Agricultural Engineering Research, Vol. 65, pp.15-22, 1996.

F J Ruiz, Nuria Agell, Cecilio Angulo, Monica Sanchez, “A qualitative learning system for human sensory abilities in adjustment tasks” In 26th International workshop on qualitative reasoningAt: Playa Vista, California, Estados Unidos de América, 2012.

A S Franca, J C F Mendonca, S D Oliveira, “Composition of green and roasted coffees of different cup qualities”, LWT - Food Science and Technology, Vol. 38, No. 7, pp.709–715, 2005.

A Putranto, X D Chen, “Roasting of Barley and Coffee Modeled Using the Lumped-Reaction Engineering Approach (L-REA)” Drying Technology, Vol. 30, No. 5, pp.475–483, 2012.

R P Kachru, R K Gupta, A Alam, Physicochemical constituents and engineering properties Of food crops (Scientific Publishers), Jodhpur, 1994.

R L Stroshine, Physical properties of agricultural materials and food products (West Lafayette, Ind), New York, 2004.

B M Stahl, Grain bin measurements, (USDA Circular), Washington DC, 1950.

R T Fowler, F A Wyatt, “The effect of moisture content on the angle of repose of granular solids”, Australian J. Chem.Eng, Vol.1, pp.5-8, 1960.

G A Anderson, C J Bern, Dynamic Angle of Repose of Corncobs Placed by Three Mechanical Means, (IOWA State University), Inggris, 1984.

Edward Lau (Deceased), Preformulation Studies in Separation Science and Technology-Handbook of Modern Pharmaceutical Analysis Copyright, (Academic Press A Harcourt Science and Technology Company), USA, 2001.

J Khazaei, S Ghanbari, “New method for simultaneously measuring the angles of repose and frictional properties of wheat grains”, International Agrophysi, Vol. 24, pp.275-286, 2010.

J Baggenstoss, L Poisson, R Luethi, R Perren, F Escher, ”Influence of Water Quench Cooling on Degassing and Aroma Stability of Roasted Coffee”, J. Agric. Food Chem, vol. 55, no. 16, pp. 6685–6691, 2007.

H G Schwartzberg, Batch Coffee Roasting; Roasting Energy Use; Reducing That Use. (In Yanniotis, S., Taoukis, P., Stoforos, N.G. & Karathanos, V.T., eds. Advances in Frood Process Engineering Research and Applications. 1st ed (Springer), New York, 2013.

B Lokker, Coffee Roasts from Light to Dark, Coffee Crossroads, In Online available at: . Accessed on 09/16/2019, 2013

Mattia, How Coffee Roasting Levels Affect Flavors, In Online available at:J Accessed on 9/16/2019. 2017



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