Effects of Roast Levels on the Physical Properties, Microbial Contaminants, and Cup Quality of Arabica Coffee

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Andres A. Basalong Von Y. Amado Hazen Lyn B. Talbino

Abstract

Turning raw green coffee beans into roasted coffee beans and other products cannot be completed without the roasting process. However, information on the influence of roast levels on the essential qualities of Arabica coffee is scant. This study was conducted to determine the effects of roast levels on the physical properties, microbial contaminants, and cup quality of Arabica coffee. Wet processed BSU-Red Bourbon Arabica coffee green coffee beans were roasted in a 250g-capacity drum-type roaster at three roast levels: light, medium, and dark. The changes in physical properties such as roasted bean dimensions and volume, roast volume, weight loss, and bulk density were observed and analyzed. Results indicated that dark roasted coffee had the highest change in bean size and volume, roast volume, weight loss, and lowest bulk density. Fungal species Saccharomyces cerevisiae and Penicillium sp. were found in the green coffee beans before roasting but were not detected in the roasted coffee beans. Arabica coffee roasted in the three roast levels were all classified as specialty although medium roast scored better than light and dark roasts. The result can be used as a guide in enhancing the development of roasted coffee products towards satisfaction in the consumption of quality Arabica coffee.

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References

Abasanbi, A. (2010). Assessment of Coffee Quality and Its Related Problems in Jimma Zone of Oromia Regional State. MSc thesis in Agriculture (Horticulture). 141p. Jimma (Ethiopia): Jimma University. https://cgspace.cgiar.org/handle/10568/2453

Alvindia, D.G., & Acda, M.A. (2010). Mycoflora of coffee beans in the Philippines. Int. Soc. Southeast Asian Agric. Sci., 16: 116-125.

Ameyu, M.A. (2016). Physical Quality Analysis of Roasted Arabica Coffee Beans Subjected to Different Harvesting and Postharvest Processing Methods in Eastern Ethiopia. Food Science and Quality Management, 57: 1-9. https://core.ac.uk/download/pdf/234684472.pdf

Basalong, A., Amado, V., & Talbino, H. (2020). Impact of the different postharvest processing methods on the occurrence of Ochratoxin A and cupping quality of Arabica coffee. Mountain Journal of Science and Interdisciplinary Research, 80(1): 87-97.

Bustos-Vanegas, J. (2018). Developing predictive models for determining physical properties of coffee beans during roasting process. Industrial Crops and Products, 112: 839-845

Clarke, R. (1985). Green coffee processing. In: Clifford, M., and Wilson, K. Coffee botany, biochemistry and production of beans and beverage. Croom Helm, London. 149-196.

Clifford, M.N. (1985). Chlorogenic Acids Chap. 5. In R.J. Clarke & R. Macrae (Eds.), Coffee volume 1: Chemistry (pp. 153–202). Amsterdam: Elsevier Applied Science.

Coffee Review. (n.d.) Roast names. https://www.coffeereview.com/coffee-reference/coffee-basics/coffee-language/roast-names/

Culiao, A.L., & Barcelo, J.M. (2015). Fungal and mycotoxin contamination of coffee beans in Benguet Province, Philippines. Food Addit Contam Part A Chem Anal Control Expo Risk Assess, 32(2): 250-260. https://doi.org/10.1080/19440049.2014.1001796

Department of Agriculture-Cordillera Administrative Region. (2016). Value chain analysis: Coffee. Department of Agriculture. Philippine Rural Development Project. Regional Project Coordination Office-Cordillera Administrative Region. Pp. 4-36.

Dinçer, F., Gedik, S., & Guzel, S.O. (2016). New Approach In Gastronomy: Third Wave Coffee. The Journal of International Social Research, 9: 811-814.

Dutra, E.R., Oliveira, S., Franca, S., Ferraz, V., & Alfonso, R. (2001). 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, 47: 241-246.

Franca, A., Mendoca, C., & Oliveira, S. (2005). Composition of green and roasted coffees of different cup qualities. Food Science and Technology, 38: 709-715.

Frisullo, P., Delnobile, M., Barnaba, M., Navarini, L., & Suggiliverani, F. (2010). Coffee Arabica beans microstructural changes induced by roasting: An X-Ray Microtographic Investigation. Proceedings of 23rd International Scientific Conference on Coffee Science (ASIC), Bali, Indonesia. 553-558.

Frisvad, J., & Samson, R. (2004). Polyphasic taxonomy of Penicillium subgenus Penicillium. A guide to identification of food and air-borne terverticillate Penicillia and their mycotoxins. Studies in Mycology, 49: 1-174.

Feria-Morales, A.M. (2002). Examining the Case of Green Coffee to Illustrate the Limitations of Grading Systems/Expert Tasters in Sensory Evaluation for Quality Control. Food Qual. Prefer., 13(6), 355–367. https://doi.org/10.1016/S0950-3293(02)00028-9

Illy, A., & Viani, R. (2005). Espresso coffee: the science of Quality (2nd Ed.). London: Elsevier Academic Press.

International Trade Center. (2002). Coffee An exporter's guide. International Trade Centre UNCTAD/WTO. Geneva. pp. 243-289

Kreger-van Rij, N.J.W. (1984). The Yeasts: A Taxonomic Study. Elsevier Biomedical Press, Amsterdam, Holland.

Kurtzman, C., Fell, J., Boekhout, T., & Robert, V. (2011). Methods for Isolation, Phenotypic Characterization and Maintenance of Yeasts. Yeasts 5th Edition. https://doi.org/10.1016/B978-0444-52149-1.00007-0

Lokker, B. (2020). Coffee roasts from light to dark. Coffee Crossroads. https://www.coffeecrossroads.com/coffee-101/coffee-roasts-from-light-to-dark

Martini, A., & Martini, A. (1993). A Taxonomic Key for the Genus Saccharomyces. Systematic and Applied Microbiology, 16(1): 113-119. https:// doi.org/10.1016/S0723-2020(11)80255-9

Masoud, W., Cesar, L.B., Jespersen, L., & Jakobsen, M. (2004). Yeast involved in fermentation of Coffea arabica in East Africa determined by genotyping and by direct denaturating gradient gel electrophoresis. Yeast, 21(7): 549-556.

Mekonen, H. (2009). Influence of Genotype, Location and processing methods on the quality of coffee (Coffee arabica L.). An M.Sc. Dissertation, presented to the school of Graduate studies of Hawasa University, Hawasa, Ethiopia. Pp. 42-71

Mendes, C., De Menezes, C., Aparecida, M., & da Silva, A. (2001). Optimization of the roasting of robusta coffee (C. canephora conillon) using acceptability tests and RSM. Food Quality Preference, 12, 153-162.

Mwithiga, G., & Jindal, V. (2007). Changes in properties of coffee brew due to roasting. World Applied Science Journal, 2(5): 527-535.

Mwithiga, G., & Jindal, V. (2003). Physical changes during coffee roasting in rotary conduction-type heating units. J. Food Process Engineer, 26: 543-558.

Noor-Aliah, A., Fareez-Edzuan, A., & Noor-Diana, A. (2015). A review of quality coffee roasting degree evaluation. Journal of Applied Science and Agriculture, 10(7): 18-23.

Oksnevad, D. (2019). The differences between 1st, 2nd and 3rd wave coffee. https://www.drivencoffee.com/blog/coffee-waves-explained/

Petracco, M. (2000). Organoleptic properties of Espresso coffee as influenced by coffee botanical varieties. In: Sera, T.; Soccol, C.R., Pandey, A. and Roussos, S. (Eds.), Coffee Biotechnology and Quality. Kluwer academic Publishers, Dordrecht. pp. 347-355.

Philippine Coffee Board. (2017). Philippine Coffee Board, Inc. Kape Pilipino – Green Coffee Quality Grading Competition Score Sheet. http:// philcoffeeboard.com/wp-content/uploads/2017/03/kp-results-v3.pdf

Philippine Coffee Quality Competition. (2018). TOP 12: Arabica Category. https://www.facebook.com/phcoffeeQC/

Philippine Information Agency-Cordillera Administrative Region. (2018). Benguet-grown Arabica coffee dominates 2018 Philippine Coffee Quality Competition. Herald Express. https://www.baguioheraldexpressonline.com/benguet-grown-arabica-coffee-dominates-2018philippine-coffee-quality-competition/

Pitt, J.I. (2000). A laboratory guide to common Penicillium species. 3rd ed. CSIRO, 197 p.

Pittia, P., Nicoli, M., & Sacchetti, G. (2007). Effect of moisture and water activity on textural properties of raw and roasted coffee beans. Journal of Texture Studies, 38: 116-134.

Prodolliet, J. (2005). Coffee Quality Assurance: Current Tools and Perspectives. In: 20th International Scientific Colloquium on Coffee. Bangalore. pp. 120-145

Raper, K.B., & Thom, C. (1949). A Manual of the Penicillia. The Williams & Wilkins Company, Baltimore.

Rodrigues, M., Borges, M., Franca, A., Oliveira, L., & Correa, P. (2002). Evaluation of physical properties of coffee during roasting. Agricultural Engineering International: the CIGR Journal of Scientific Research and Development. Presented at the ASAE Annual International Meeting/CIGR XVth World Congress. Chicago, Il.

Silva, C., Schwan, R., Dias, E., & Wheals, A. (2000). Microbial diversity during maturation and natural processing of coffee cherries of Coffea Arabica in Brazil. Int. J. Food. Microbiol., 60: 251–260.

Sualeh, A., Mohammed, A., & E. Solomon. (2014). Processing method, variety, and roasting duration effect on physical quality attributes of roasted Arabica coffee beans. Sky Journal of Agricultural Research, 3(5): 53-61.

Thom, C. (1930). The Penicillia. The Williams & Wilkins Company, Baltimore.