Chemical composition and antioxidant activity of the silverskin of three varieties of Coffea arabica L.
Keywords:
phytochemical analysis, coffee, extraction methods, nutraceutical potential, agro-industrial by-product
Abstract
The silverskin (SS) of Coffea arabica L., a byproduct of coffee processing, represents a potential source of bioactive compounds with nutraceutical properties. The chemical composition (residual moisture, ash, fats, proteins, and minerals) and antioxidant capacity of the SS from three varieties of C. arabica (Acauã [AW], Sarchimor Rojo [CR], and Catucaí Amarillo [CA]) from the province of El Oro, Ecuador, were evaluated. The extraction of secondary metabolites (total phenols and caffeine) was performed for 60 min using ultrasound (US: 30 °C, 40 Hz) and dynamic digestion (D: 60 °C, 60 rpm), employing an ethanol:water mixture of (70:30 % v/v) and a plant material:solvent ratio of 20:80 % w/v. Total phenols were quantified using the Folin-Ciocalteu method, and caffeine analysis was performed through high-performance liquid chromatography (HPLC) with DAD detection. The evaluated samples met the residual moisture (RM) and total ash content requirements according to the NTE INEN standards, also exhibiting low percentages of fat and protein. The CR variety stood out with 44.8 mg.g⁻¹ of K and 24.9 mg.g⁻¹ of N. Method D extracted the highest amount of phenolic compounds, with CR recording the highest content at 85.0 mg GAE.g⁻¹ of dry extract (DE), which positively correlated with a higher Trolox equivalent antioxidant capacity (DPPH: 108.61 mg TEAC.g⁻¹ DE; FRAP: 122.96 mg TEAC.g⁻¹ DE). In contrast, caffeine levels were higher for the AW variety extracted by US (128.44 mg.g⁻¹ DE), being statistically different from the rest. The three varieties meet regulatory standards and demonstrate that SS is a raw material of great interest to the food and pharmaceutical industries.
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References
Association of Official Analytical Chemists, Inc. (AOAC). (1990). Official methods of analysis. Association of Official Analytical Chemists, Inc.
Barreto Peixoto, J. A. B., Andrade, N., Machado, S., Costa, A. S. G., Puga, H., Oliveira, M. B. P. P., Martel, F., & Alves, R. C. (2022). Valorizing coffee silverskin based on its phytochemicals and antidiabetic potential: From lab to a pilot scale. Foods, 11(12), Artículo 1671. https://doi.org/10.3390/foods11121671
Benzie, I. F. F., & Strain, J. J. (1996). The ferric reducing ability of plasma (FRAP) as a measure of "antioxidant power": The FRAP assay. Analytical Biochemistry, 239(1), 70-76. https://doi.org/10.1006/abio.1996.0292
Biondić Fučkar, V., Božić, A., Jukić, A., Krivohlavek, A., Jurak, G., Tot, A., Serdar, S., Žuntar, I., & Režek Jambrak, A. (2023). Coffee silver skin-health safety, nutritional value, and microwave extraction of proteins. Foods, 12(3), 518. https://doi.org/10.3390/foods12030518
Bobková, A., Poláková, K., Demianová, A., Belej, Ľ., Bobko, M., Jurčaga, L., Gálik, B., Novotná, I., Iriondo-DeHond, A., & del Castillo, M. D. (2022). Comparative analysis of selected chemical parameters of Coffea arabica, from cascara to silverskin. Foods, 11(8), Artículo 1082. https://doi.org/10.3390/foods11081082
Bojórquez-Quintal, E., Xotlanihua-Flores, D., Bacchetta, L., Diretto, G., Maccioni, O., Frusciante, S., Rojas-Abarca, L. M., & Sánchez-Rodríguez, E. (2024). Bioactive compounds and valorization of coffee by-products from the origin: A circular economy model from local practices in Zongolica, México. Plants, 13(19), Artículo 2741. https://doi.org/10.3390/plants13192741
Brand-Williams, W., Cuvelier, M. E., & Berset, C. (1995). Use of a free radical method to evaluate antioxidant activity. LWT - Food Science and Technology, 28(1), 25-30. https://doi.org/10.1016/S0023-6438(95)80008-5
Campo Fernández, M., Palacios Marín, M. C., Panta Cuenca, A. P., Matute Castro, N. L., Cuesta Rubio, O., Márquez Hernández, I., & Jaramillo Jaramillo, C. G. (2024). Composición química y capacidad antioxidante de tres variedades de cascarilla de café (Coffea arabica). Revista Colombiana de Química. 53(2), 3-12. https://doi.org/10.15446/rev.colomb.quim.v53n2.117439
Campo-Fernández, M., Granja-Rizzo, D. F., Matute-Castro, N. L., Cuesta-Rubio, O., & Márquez-Hernández, I. (2021). Microencapsulación mediante secado por atomización a partir de un extracto de los cálices de Hibiscus sabdariffa L. Revista Colombiana de Química, 50(1), 40-50. https://doi.org/10.15446/rev.colomb.quim.v50n1.88424
Eticha, S., & Bedassa, T. (2020). Determination of caffeine in coffee samples by high performance liquid chromatography and ultra violet-visible spectrophotometry methods from Wollega. International Journal of Biochemistry, Biophysics & Molecular Biology, 5(1), 8-15. https://doi.org/10.11648/j.ijbbmb.20200501.12
Fonseca-García, L., Calderón-Jaimes, L., & Rivera, M. (2014). Antioxidant capacity and total phenol content in coffee and coffee by-products produced and marketed in Norte de Santander (Colombia). Vitae, Revista de la Facultad de Química Farmacéutica, 21(3), 228-236. http://www.scielo.org.co/pdf/vitae/v21n3/v21n3a08.pdf
Franca, A. S., Basílio, E. P., Resende, L. M., Fante, C. A., & Oliveira, L. S. (2024). Coffee silverskin as a potential ingredient for functional foods: Recent advances and a case study with chocolate cake. Foods, 13(23), Artículo 3935. https://doi.org/10.3390/foods13233935
Gottstein, V., Bernhardt, M., Dilger, E., Keller, J., Breitling-Utzmann, C. M., Schwarz, S., Kuballa, T., Lachenmeier, D. W., & Bunzel, M. (2021). Coffee silver skin: Chemical characterization with special consideration of dietary fiber and heat-induced contaminants. Foods, 10(8), Artículo 1705. https://doi.org/10.3390/foods10081705
Hayes, C., Nurkolis, F., Laksemi, D. A. A. S., Chung, S., Park, M. N., Choi, M., Choi, J., Darmaputra, I. G. N., Gunawan, W. B., Lele, J. A. J. M. N., Khumaidi, M. A., Taslim, N. A., & Kim, B. (2023). Coffee silverskin phytocompounds as a novel anti-aging functional food: A pharmacoinformatic approach combined with in vitro study. Molecules, 28(20), Artículo 7037. https://doi.org/10.3390/molecules28207037
Jamovi project. (2022). jamovi (Versión 2.3.2) [Software de computadora]. https://www.jamovi.org
Jung, S., Gu, S., Lee, S. H., & Jeong, Y. (2021). Effect of roasting degree on the antioxidant properties of espresso and drip coffee extracted from Coffea arabica cv. Java. Applied Sciences, 11(15), Artículo 7025. https://doi.org/10.3390/app11157025
Kiss, A., Papp, V. A., Pál, A., Prokisch, J., Mirani, S., Toth, B. E., & Alshaal, T. (2025). Comparative study on antioxidant capacity of diverse food matrices: Applicability, suitability and inter-correlation of multiple assays to assess polyphenol and antioxidant status. Antioxidants, 14(3), Artículo 317. https://doi.org/10.3390/antiox14030317
Kristanto, G. A., & Wijaya, H. (2018). Assessment of spent coffee ground (SCG) and coffee silverskin (CS) as refuse derived fuel (RDF). IOP Conference Series: Earth and Environmental Science, 195(1), Artículo 012056. https://doi.org/10.1088/1755-1315/195/1/012056
Machado, M., Espírito Santo, L. E., Machado, S., Lobo, J. C., Costa, A. S. G., Oliveira, M. B. P. P., Ferreira, H., & Alves, R. C. (2023). Bioactive potential and chemical composition of coffee by-products: From pulp to silverskin. Foods, 12(12), Artículo 2354. https://doi.org/10.3390/foods12122354
Martins de Sá, D. L., Brayon Batista, E., Hasper de Souza, M. C., Massarolo, K. C., & Lopes Ricardo, L. (2024). Métodos de extração de compostos fenólicos da casca melosa do Coffea arábica L. Revista JRG de Estudos Acadêmicos, 7(14), Artículo e141225. https://mail.revistajrg.com/index.php/jrg/article/view/1225/1033
Martuscelli, M., Esposito, L., Di Mattia, C. D., Ricci, A., & Mastrocola, D. (2021). Caracterización de la cáscara plateada del café como posible ingrediente alimentario seguro. Foods, 10(6), Artículo 1367. https://doi.org/10.3390/foods10061367
Ministerio de Agricultura y Ganadería [MAG]. (2021). Informe de rendimientos objetivos de café 2021. Sistema de Información Pública Agropecuaria (SIGMA). https://sipa.agricultura.gob.ec/index.php/rendimientos-de-cafe-2021
Nolasco, A., Squillante, J., Esposito, F., Velotto, S., Romano, R., Aponte, M., Giarra, A., Toscanesi, M., Montella, E., & Cirillo, T. (2022). Coffee silverskin: Chemical and biological risk assessment and health profile for its potential use in functional foods. Foods, 11(18), Artículo 2834. https://doi.org/10.3390/foods11182834
Pillco Cochan, C.J., Guzmán Loayza, D., & Cuéllar Bautista, J.E. (2021). Composición físico química y análisis proximal del fruto de sofaique “Geoffroea decorticans (Hook. et Arn.)” procedente de la región Ica-Perú. Revista de la Sociedad Química del Perú, 87(1), 14-25. https://doi.org/10.37761/rsqp.v87i1.319
Prakash, P., & Doan, H. V. (2022). Effect of coffee silverskin enriched diet to enhance the immunological and growth parameters of Nile tilapia (Oreochromis niloticus). Archives of Razi Institute, 77(3), 1281-1289. https://doi.org/10.22092/ARI.2021.356820.1920
Prandi, B., Ferri, M., Monari, S., Zurlini, C., Cigognini, I., Verstringe, S., Schaller, D., Walter, M., Navarini, L., Tassoni, A., Sforza, S., & Tedeschi, T. (2021). Extraction and chemical characterization of functional phenols and proteins from coffee (Coffea arabica) by-products. Biomolecules, 11(11), Artículo 1571. https://doi.org/10.3390/biom11111571
Santanatoglia, A., Alessandroni, L., Mannozzi, C., Marconi, R., Piatti, D., Sagratini, G., & Caprioli, G. (2024). Valorization of spent coffee ground and coffee silverskin as a source of nutrients and bioactive compounds. Future Postharvest and Food, 1(1), 61-81. https://doi.org/10.1002/fpf2.12007
Servicio Ecuatoriano de Normalización [INEN]. (2016). Café tostado en grano o molido. Requisitos (NTE INEN 1123).
Servicio Ecuatoriano de Normalización [INEN]. (2017). Hierbas aromáticas. Requisitos (NTE INEN 2392).
Taweekayujan, S., Somngam, S., & Pinnarat, T. (2023). Optimization and kinetics modeling of phenolics extraction from coffee silverskin in deep eutectic solvent using ultrasound-assisted extraction. Heliyon, 9(7), Artículo e17942. https://doi.org/10.1016/j.heliyon.2023.e17942
Ullah, S., Ullah, M., Rahim, G., Khan, S., & Ullah, I. (2023). Proximate analysis and mineral composition of some selected medicinal plants of Malakand Division, Pakistan. Natural Products Chemistry & Research, 11, 8-12. Downloads/75afee1a-ee27-44e5-83b9-b73edd64432c..pdf
Vargas-Sánchez, R. D., Torres-Martínez, B. D. M., Torrescano-Urrutia, G. R., & Sánchez-Escalante, A. (2023). Caracterización fisicoquímica, tecno-funcional y antioxidante de la piel plateada del café. Biotecnia, 25(1), 43-50. https://doi.org/10.18633/biotecnia.v25i1.1755
Zengin, G., Sinan, K. I., Mahomoodally, M. F., Angeloni, S., Mustafa, A. M., Vittori, S., Maggi, F., & Caprioli, G. (2020). Chemical composition, antioxidant and enzyme inhibitory properties of different extracts obtained from spent coffee ground and coffee silverskin. Foods, 9(6), Artículo 713. https://doi.org/10.3390/foods9060713
Barreto Peixoto, J. A. B., Andrade, N., Machado, S., Costa, A. S. G., Puga, H., Oliveira, M. B. P. P., Martel, F., & Alves, R. C. (2022). Valorizing coffee silverskin based on its phytochemicals and antidiabetic potential: From lab to a pilot scale. Foods, 11(12), Artículo 1671. https://doi.org/10.3390/foods11121671
Benzie, I. F. F., & Strain, J. J. (1996). The ferric reducing ability of plasma (FRAP) as a measure of "antioxidant power": The FRAP assay. Analytical Biochemistry, 239(1), 70-76. https://doi.org/10.1006/abio.1996.0292
Biondić Fučkar, V., Božić, A., Jukić, A., Krivohlavek, A., Jurak, G., Tot, A., Serdar, S., Žuntar, I., & Režek Jambrak, A. (2023). Coffee silver skin-health safety, nutritional value, and microwave extraction of proteins. Foods, 12(3), 518. https://doi.org/10.3390/foods12030518
Bobková, A., Poláková, K., Demianová, A., Belej, Ľ., Bobko, M., Jurčaga, L., Gálik, B., Novotná, I., Iriondo-DeHond, A., & del Castillo, M. D. (2022). Comparative analysis of selected chemical parameters of Coffea arabica, from cascara to silverskin. Foods, 11(8), Artículo 1082. https://doi.org/10.3390/foods11081082
Bojórquez-Quintal, E., Xotlanihua-Flores, D., Bacchetta, L., Diretto, G., Maccioni, O., Frusciante, S., Rojas-Abarca, L. M., & Sánchez-Rodríguez, E. (2024). Bioactive compounds and valorization of coffee by-products from the origin: A circular economy model from local practices in Zongolica, México. Plants, 13(19), Artículo 2741. https://doi.org/10.3390/plants13192741
Brand-Williams, W., Cuvelier, M. E., & Berset, C. (1995). Use of a free radical method to evaluate antioxidant activity. LWT - Food Science and Technology, 28(1), 25-30. https://doi.org/10.1016/S0023-6438(95)80008-5
Campo Fernández, M., Palacios Marín, M. C., Panta Cuenca, A. P., Matute Castro, N. L., Cuesta Rubio, O., Márquez Hernández, I., & Jaramillo Jaramillo, C. G. (2024). Composición química y capacidad antioxidante de tres variedades de cascarilla de café (Coffea arabica). Revista Colombiana de Química. 53(2), 3-12. https://doi.org/10.15446/rev.colomb.quim.v53n2.117439
Campo-Fernández, M., Granja-Rizzo, D. F., Matute-Castro, N. L., Cuesta-Rubio, O., & Márquez-Hernández, I. (2021). Microencapsulación mediante secado por atomización a partir de un extracto de los cálices de Hibiscus sabdariffa L. Revista Colombiana de Química, 50(1), 40-50. https://doi.org/10.15446/rev.colomb.quim.v50n1.88424
Eticha, S., & Bedassa, T. (2020). Determination of caffeine in coffee samples by high performance liquid chromatography and ultra violet-visible spectrophotometry methods from Wollega. International Journal of Biochemistry, Biophysics & Molecular Biology, 5(1), 8-15. https://doi.org/10.11648/j.ijbbmb.20200501.12
Fonseca-García, L., Calderón-Jaimes, L., & Rivera, M. (2014). Antioxidant capacity and total phenol content in coffee and coffee by-products produced and marketed in Norte de Santander (Colombia). Vitae, Revista de la Facultad de Química Farmacéutica, 21(3), 228-236. http://www.scielo.org.co/pdf/vitae/v21n3/v21n3a08.pdf
Franca, A. S., Basílio, E. P., Resende, L. M., Fante, C. A., & Oliveira, L. S. (2024). Coffee silverskin as a potential ingredient for functional foods: Recent advances and a case study with chocolate cake. Foods, 13(23), Artículo 3935. https://doi.org/10.3390/foods13233935
Gottstein, V., Bernhardt, M., Dilger, E., Keller, J., Breitling-Utzmann, C. M., Schwarz, S., Kuballa, T., Lachenmeier, D. W., & Bunzel, M. (2021). Coffee silver skin: Chemical characterization with special consideration of dietary fiber and heat-induced contaminants. Foods, 10(8), Artículo 1705. https://doi.org/10.3390/foods10081705
Hayes, C., Nurkolis, F., Laksemi, D. A. A. S., Chung, S., Park, M. N., Choi, M., Choi, J., Darmaputra, I. G. N., Gunawan, W. B., Lele, J. A. J. M. N., Khumaidi, M. A., Taslim, N. A., & Kim, B. (2023). Coffee silverskin phytocompounds as a novel anti-aging functional food: A pharmacoinformatic approach combined with in vitro study. Molecules, 28(20), Artículo 7037. https://doi.org/10.3390/molecules28207037
Jamovi project. (2022). jamovi (Versión 2.3.2) [Software de computadora]. https://www.jamovi.org
Jung, S., Gu, S., Lee, S. H., & Jeong, Y. (2021). Effect of roasting degree on the antioxidant properties of espresso and drip coffee extracted from Coffea arabica cv. Java. Applied Sciences, 11(15), Artículo 7025. https://doi.org/10.3390/app11157025
Kiss, A., Papp, V. A., Pál, A., Prokisch, J., Mirani, S., Toth, B. E., & Alshaal, T. (2025). Comparative study on antioxidant capacity of diverse food matrices: Applicability, suitability and inter-correlation of multiple assays to assess polyphenol and antioxidant status. Antioxidants, 14(3), Artículo 317. https://doi.org/10.3390/antiox14030317
Kristanto, G. A., & Wijaya, H. (2018). Assessment of spent coffee ground (SCG) and coffee silverskin (CS) as refuse derived fuel (RDF). IOP Conference Series: Earth and Environmental Science, 195(1), Artículo 012056. https://doi.org/10.1088/1755-1315/195/1/012056
Machado, M., Espírito Santo, L. E., Machado, S., Lobo, J. C., Costa, A. S. G., Oliveira, M. B. P. P., Ferreira, H., & Alves, R. C. (2023). Bioactive potential and chemical composition of coffee by-products: From pulp to silverskin. Foods, 12(12), Artículo 2354. https://doi.org/10.3390/foods12122354
Martins de Sá, D. L., Brayon Batista, E., Hasper de Souza, M. C., Massarolo, K. C., & Lopes Ricardo, L. (2024). Métodos de extração de compostos fenólicos da casca melosa do Coffea arábica L. Revista JRG de Estudos Acadêmicos, 7(14), Artículo e141225. https://mail.revistajrg.com/index.php/jrg/article/view/1225/1033
Martuscelli, M., Esposito, L., Di Mattia, C. D., Ricci, A., & Mastrocola, D. (2021). Caracterización de la cáscara plateada del café como posible ingrediente alimentario seguro. Foods, 10(6), Artículo 1367. https://doi.org/10.3390/foods10061367
Ministerio de Agricultura y Ganadería [MAG]. (2021). Informe de rendimientos objetivos de café 2021. Sistema de Información Pública Agropecuaria (SIGMA). https://sipa.agricultura.gob.ec/index.php/rendimientos-de-cafe-2021
Nolasco, A., Squillante, J., Esposito, F., Velotto, S., Romano, R., Aponte, M., Giarra, A., Toscanesi, M., Montella, E., & Cirillo, T. (2022). Coffee silverskin: Chemical and biological risk assessment and health profile for its potential use in functional foods. Foods, 11(18), Artículo 2834. https://doi.org/10.3390/foods11182834
Pillco Cochan, C.J., Guzmán Loayza, D., & Cuéllar Bautista, J.E. (2021). Composición físico química y análisis proximal del fruto de sofaique “Geoffroea decorticans (Hook. et Arn.)” procedente de la región Ica-Perú. Revista de la Sociedad Química del Perú, 87(1), 14-25. https://doi.org/10.37761/rsqp.v87i1.319
Prakash, P., & Doan, H. V. (2022). Effect of coffee silverskin enriched diet to enhance the immunological and growth parameters of Nile tilapia (Oreochromis niloticus). Archives of Razi Institute, 77(3), 1281-1289. https://doi.org/10.22092/ARI.2021.356820.1920
Prandi, B., Ferri, M., Monari, S., Zurlini, C., Cigognini, I., Verstringe, S., Schaller, D., Walter, M., Navarini, L., Tassoni, A., Sforza, S., & Tedeschi, T. (2021). Extraction and chemical characterization of functional phenols and proteins from coffee (Coffea arabica) by-products. Biomolecules, 11(11), Artículo 1571. https://doi.org/10.3390/biom11111571
Santanatoglia, A., Alessandroni, L., Mannozzi, C., Marconi, R., Piatti, D., Sagratini, G., & Caprioli, G. (2024). Valorization of spent coffee ground and coffee silverskin as a source of nutrients and bioactive compounds. Future Postharvest and Food, 1(1), 61-81. https://doi.org/10.1002/fpf2.12007
Servicio Ecuatoriano de Normalización [INEN]. (2016). Café tostado en grano o molido. Requisitos (NTE INEN 1123).
Servicio Ecuatoriano de Normalización [INEN]. (2017). Hierbas aromáticas. Requisitos (NTE INEN 2392).
Taweekayujan, S., Somngam, S., & Pinnarat, T. (2023). Optimization and kinetics modeling of phenolics extraction from coffee silverskin in deep eutectic solvent using ultrasound-assisted extraction. Heliyon, 9(7), Artículo e17942. https://doi.org/10.1016/j.heliyon.2023.e17942
Ullah, S., Ullah, M., Rahim, G., Khan, S., & Ullah, I. (2023). Proximate analysis and mineral composition of some selected medicinal plants of Malakand Division, Pakistan. Natural Products Chemistry & Research, 11, 8-12. Downloads/75afee1a-ee27-44e5-83b9-b73edd64432c..pdf
Vargas-Sánchez, R. D., Torres-Martínez, B. D. M., Torrescano-Urrutia, G. R., & Sánchez-Escalante, A. (2023). Caracterización fisicoquímica, tecno-funcional y antioxidante de la piel plateada del café. Biotecnia, 25(1), 43-50. https://doi.org/10.18633/biotecnia.v25i1.1755
Zengin, G., Sinan, K. I., Mahomoodally, M. F., Angeloni, S., Mustafa, A. M., Vittori, S., Maggi, F., & Caprioli, G. (2020). Chemical composition, antioxidant and enzyme inhibitory properties of different extracts obtained from spent coffee ground and coffee silverskin. Foods, 9(6), Artículo 713. https://doi.org/10.3390/foods9060713
Published
2026-06-15
How to Cite
Márquez, I., Campo , M., Bustamante , A., Echeverría , R., Cuesta , O., & Matute, N. (2026). Chemical composition and antioxidant activity of the silverskin of three varieties of Coffea arabica L. Revista De La Facultad De Agronomía De La Universidad Del Zulia, 43(3), e264334. Retrieved from https://produccioncientifica.luz.edu.ve/index.php/agronomia/article/view/45727
Issue
Section
Food Technology
Copyright (c) 2026 Ingrid Márquez Hernández, Mercedes Campo Fernández, Arantxa Ainoa Bustamante Quinde, Ronald Steeven Echeverría Loayza, Osmany Cuesta Rubio, Nubia Lisbeth Matute Castro
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
