The main aim of this study was to evaluate the impact of mechanical drying on the sensory quality of specialty coffee produced on three Colombian coffee farms. The technique involved a study of the coffee bean drying process parameters, such as temperature (35, 45 and 55 ℃), airflow (100 m3/min∙m2) and thickness (0.2 m) for mechanical drying, vs conventional drying in the open sun until 11% of moisture content was reached. For mechanical drying, the effective diffusion coefficient, electrical conductivity and drying kinetics were evaluated. A sensory test was performed for three storage periods (3, 6 and 9 months) using the Specialty Coffee Association (SCA) protocol. The results showed that the effective diffusion coefficient varied from 3.21 to 8.02 × 10−7 m2/s for mechanical drying and from 4.21 × 10−11 m2/s for drying in the open sun. The time drying time was established at 20.35 ± 0.06, 29.10 ± 0.09 and 71.52 ± 0.11 hours for mechanical drying at 55 ℃, 45 ℃ and 35 ℃ respectively and 54.48 ± 11.37 hours for drying in the open sun system. The average moisture content at the end of all drying operations was 12.5%. Electrical conductivity rose from 11.71 to 16.86 µS/cm∙g at drying temperatures ranging from 35 to 55 ℃. The sensory test revealed that storage duration had no effect on the quality of the coffee drink when in touch with the drying process, with mechanical drying yielding higher sensory ratings. The coffee beans were dried at 55 ℃, yielding coffee samples with SCA scores more than 85 points. In overall, it is determined that the convective mechanical drying method is a viable approach for the processing of specialty coffee beans since it allows for the retention of high-quality sensory qualities, allowing it to command higher market pricing.
Citation: Esteban Largo-Avila, Carlos Hernán Suarez-Rodríguez, Jorge Latorre Montero, Madison Strong, Osorio-Arias Juan. The influence of hot-air mechanical drying on the sensory quality of specialty Colombian coffee[J]. AIMS Agriculture and Food, 2023, 8(3): 789-803. doi: 10.3934/agrfood.2023042
The main aim of this study was to evaluate the impact of mechanical drying on the sensory quality of specialty coffee produced on three Colombian coffee farms. The technique involved a study of the coffee bean drying process parameters, such as temperature (35, 45 and 55 ℃), airflow (100 m3/min∙m2) and thickness (0.2 m) for mechanical drying, vs conventional drying in the open sun until 11% of moisture content was reached. For mechanical drying, the effective diffusion coefficient, electrical conductivity and drying kinetics were evaluated. A sensory test was performed for three storage periods (3, 6 and 9 months) using the Specialty Coffee Association (SCA) protocol. The results showed that the effective diffusion coefficient varied from 3.21 to 8.02 × 10−7 m2/s for mechanical drying and from 4.21 × 10−11 m2/s for drying in the open sun. The time drying time was established at 20.35 ± 0.06, 29.10 ± 0.09 and 71.52 ± 0.11 hours for mechanical drying at 55 ℃, 45 ℃ and 35 ℃ respectively and 54.48 ± 11.37 hours for drying in the open sun system. The average moisture content at the end of all drying operations was 12.5%. Electrical conductivity rose from 11.71 to 16.86 µS/cm∙g at drying temperatures ranging from 35 to 55 ℃. The sensory test revealed that storage duration had no effect on the quality of the coffee drink when in touch with the drying process, with mechanical drying yielding higher sensory ratings. The coffee beans were dried at 55 ℃, yielding coffee samples with SCA scores more than 85 points. In overall, it is determined that the convective mechanical drying method is a viable approach for the processing of specialty coffee beans since it allows for the retention of high-quality sensory qualities, allowing it to command higher market pricing.
| [1] | International Coffee Organization (ICO) (2020) Coffee Market Report. Available from: http://www.ico.org/documents/cy2020-21/cmr-1020-e.pdf. |
| [2] | Franca AS, Oliveira LS (2019) Chapter 17—Coffee. In: Pan Z, Zhang R, Zicari S (Eds.), Integrated Processing Technologies for Food and Agricultural By-Products, Academic Press, 413–438. https://doi.org/10.1016/B978-0-12-814138-0.00017-4 |
| [3] | Torga GN, Spers EE (2020) Chapter 2—Perspectives of global coffee demand. In: de Almeida LF, Spers EE (Eds.), Coffee Consumption and Industry Strategies in Brazil, Woodhead Publishing, 21–49. https://doi.org/10.1016/B978-0-12-814721-4.00002-0 |
| [4] |
Magalhães Júnior, AI, de Carvalho Neto, DP, De Melo Pereira GV, et al. (2021) A critical techno-economic analysis of coffee processing utilizing a modern fermentation system: Implications for specialty coffee production. Food Bioprod Process 125: 14–21. https://doi.org/10.1016/j.fbp.2020.10.010 doi: 10.1016/j.fbp.2020.10.010
|
| [5] |
de Melo Pereira GV, de Carvalho Neto DP, Magalhães Júnior AI, et al. (2019) Exploring the impacts of postharvest processing on the aroma formation of coffee beans–A review. Food Chem 272: 441–452. https://doi.org/10.1016/j.foodchem.2018.08.061 doi: 10.1016/j.foodchem.2018.08.061
|
| [6] |
Osorio-Arias J, Delgado-Arias S, Cano L, et al. (2020) Sustainable management and valorization of spent coffee grounds through the optimization of thin layer hot air-drying process. Waste Biomass Valorization 11: 5015–5026. https://doi.org/10.1007/s12649-019-00793-9 doi: 10.1007/s12649-019-00793-9
|
| [7] | Sabarez S (2016) Drying of Food Materials, Elsevier. |
| [8] |
Saavedra J, Córdova A, Navarro R, et al. (2017) Industrial avocado waste: Functional compounds preservation by convective drying process. J Food Eng 198: 81–90. https://doi.org/10.1016/j.jfoodeng.2016.11.018 doi: 10.1016/j.jfoodeng.2016.11.018
|
| [9] | Duarte Y, Chaux A, Lopez N, et al. (2017) Effects of blanching and hot air drying conditions on the physicochemical and technological properties of yellow passion fruit (Passiflora edulis Var. Flavicarpa) by‐products. J Food Process Eng 40: e12425. |
| [10] | Roa-Mejía G, Oliveros-Tascón C, Ramírez-Gómez C (2000) Utilice la Energía Solar para Secar Correctamente el Café. Avances Técnicos Cenicafé 281: 1–4. |
| [11] | Sanz-Uribe JR, Yusianto, Menon SN, et al. (2017) Chapter 3—Postharvest processing-revealing the green bean. In: Folmer B (Ed.), The Craft and Science of Coffee, Cenicafé FNC, Manizales, Colombia: Elsevier Inc., 51–79. https://doi.org/10.1016/B978-0-12-803520-7.00003-7 |
| [12] |
Silva CF, Batista LR, Abreu LM, et al. (2008) Succession of bacterial and fungal communities during natural coffee (Coffea arabica) fermentation. Food Microbiol 25: 951–957. https://doi.org/10.1016/B978-0-12-803520-7.00003-7 doi: 10.1016/B978-0-12-803520-7.00003-7
|
| [13] | Roa-Mejía G, Oliveros-Tascón CE, Parra-Coronado A, et al. (2000) El Secado Mecánico Del Café. |
| [14] |
Dong W, Hu R, Chu Z, et al. (2017) Effect of different drying techniques on bioactive components, fatty acid composition, and volatile profile of robusta coffee beans. Food Chem 234: 121–130. https://doi.org/10.1016/j.foodchem.2017.04.156 doi: 10.1016/j.foodchem.2017.04.156
|
| [15] |
Sanz-UribeJR, Velásquez-Henao J (2022) Producción de café con fermentaciones incompletas y fermentaciones prolongadas utilizando el Fermaestro®. Rev Cenicafé 73: e73105. https://doi.org/10.38141/10778/73105 doi: 10.38141/10778/73105
|
| [16] | Peñuela-Martínez AE, Pabón J, Sanz-Uribe JR (2013) Método Fermaestro: para determinar la finalización de la fermentación del mucílago de café. Av Téc Cenicafé 2013: 1–8. |
| [17] | Jurado JM, Montoya EC, Oliveros CE, et al. (2009) Método para medir el contenido de humedad del café pergamino en el secado solar del café. |
| [18] | Oliveros CE, Peñuela AE, Jurado JM (2009) Controle la humedad del café en el secado solar, utilizando el método Gravimet. Av Téc Cenicafé 387: 1–8. |
| [19] | Heldman DR, Lund DB, Sabliov C (2006) Handbook of food engineering, 2nd Edition, CRC press. https://doi.org/10.1201/9781420014372 |
| [20] | Onwude DI, Hashim N, Janius RB, et al. (2016) Modeling the thin‐layer drying of fruits and vegetables: A review Compr Rev Food Sci Food Saf 15: 599–618. https://doi.org/10.1111/1541-4337.12196 |
| [21] | Cranck J (1975) The Mathematics of Diffusion 10: 306–4549. |
| [22] | Akoy EOM (2014) Experimental characterization and modeling of thin-layer drying of mango slices. Int Food Res J 21: 1911. |
| [23] |
Hashim N, Daniel O, Rahaman E (2014) A preliminary study: Kinetic model of drying process of Pumpkins (Cucurbita Moschata) in a convective hot air dryer. Agric Agric Sci Procedia 2: 345–352. https://doi.org/10.1016/j.aaspro.2014.11.048 doi: 10.1016/j.aaspro.2014.11.048
|
| [24] |
Ayadi M, Ben Mabrouk S, Zouari I, et al. (2013) Kinetic study of the convective drying of spearmint. J Saudi Soc Agric Sci 13: 1–7. https://doi.org/10.1016/j.jssas.2013.04.004 doi: 10.1016/j.jssas.2013.04.004
|
| [25] |
Demir V, Gunhan T, Yagcioglu AK (2007) Mathematical modelling of convection drying of green table olives. Biosyst Eng 98: 47–53. https://doi.org/10.1016/j.biosystemseng.2007.06.011 doi: 10.1016/j.biosystemseng.2007.06.011
|
| [26] | ICONTEC (2005) Norma Técnica Colombiana NTC 2325. Café verde. Determinación de la pérdida de masa a 105 ℃. Colombia: Instituto Colombiano de Normas Técnicas y Certificación. |
| [27] |
de Andrade ET, Lemos IA, Dias CDA, et al. (2019) Mathematical modelling and immediate and latent quality of natural immature coffee under different drying conditions. Eng Agrícola 39: 630–638. https://doi.org/10.1590/1809-4430-eng.agric.v39n5p630-638/2019 doi: 10.1590/1809-4430-eng.agric.v39n5p630-638/2019
|
| [28] |
Rodriguez YFB, Guzman NG, Hernandez JG (2020) Effect of the postharvest processing method on the biochemical composition and sensory analysis of arabica coffee. Eng Agric 40: 177–183. https://doi.org/10.1590/1809-4430-eng.agric.v40n2p177-183/2020 doi: 10.1590/1809-4430-eng.agric.v40n2p177-183/2020
|
| [29] |
Velásquez S, Peña N, Bohórquez JC, et al. (2019) Volatile and sensory characterization of roast coffees—Effects of cherry maturity. Food Chem 274: 137–145. https://doi.org/10.1016/j.foodchem.2018.08.127 doi: 10.1016/j.foodchem.2018.08.127
|
| [30] |
Lawrence G, Symoneaux R, Maitre I, et al. (2013) Using the free comments method for sensory characterisation of Cabernet Franc wines: Comparison with classical profiling in a professional context. Food Qual Prefer 30: 145–155. https://doi.org/10.1016/j.foodqual.2013.04.005 doi: 10.1016/j.foodqual.2013.04.005
|
| [31] | Symoneaux R, Galmarini MV, Mehinagic E (2012) Comment analysis of consumer's likes and dislikes as an alternative tool to preference mapping. A case study on apples. Food Qual Prefer 24: 59–66. https://doi.org/10.1016/j.foodqual.2011.08.013 |
| [32] |
Chen XD (2007) Moisture diffusivity in food and biological materials. Dry Technol 25: 1203–1213. https://doi.org/10.1080/07373930701438592 doi: 10.1080/07373930701438592
|
| [33] | Cano Suárez HF, Ciro Velásquez HJ, Arango Tobón JC (2018) Efecto del secado y presecado mecánico previo al almacenamiento en la calidad del grano de café (Coffea arabica L.). Rev UDCA Actual Divulg Científica 21: 439–448. https://doi.org/10.31910/rudca.v21.n2.2018.1068 |
| [34] |
Dong W, Cheng K, Hu R, et al. (2018) Effect of microwave vacuum drying on the drying characteristics, color, microstructure, and antioxidant activity of green coffee beans. Molecules 23: 1146. https://doi.org/10.3390/molecules23051146 doi: 10.3390/molecules23051146
|
| [35] |
Kulapichitr F, Borompichaichartkul C, Suppavorasatit I, et al. (2019) Impact of drying process on chemical composition and key aroma components of Arabica coffee. Food Chem 291: 49–58. https://doi.org/10.1016/j.foodchem.2019.03.152 doi: 10.1016/j.foodchem.2019.03.152
|
| [36] |
Largo‐Avila E, Suárez‐Rodríguez CH, Maya JC, et al. (2023) Changes in fatty acids profile and sucrose concentration of coffee beans during drying process. J Food Process Eng 2023: e14385. https://doi.org/10.1111/jfpe.14385 doi: 10.1111/jfpe.14385
|
| [37] | Bastian F, Hutabarat OS, Dirpan A, et al. (2021) From plantation to cup: Changes in bioactive compounds during coffee processing. Foods 10: 2827. |
| [38] | Peñuela-Martínez AE, Zapata-Zapata AD, Durango-Restrepo DL (2018) Performance of different fermentation methods and the effect on coffee quality (coffea arabica L.). Coffee Sci 13: 465–476. https://doi.org/10.25186/cs.v13i4.1486 |
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Esteban Largo-Avila, Carlos Hernán Suarez-Rodríguez, Jorge Latorre Montero, Madison Strong, Osorio-Arias Juan. The influence of hot-air mechanical drying on the sensory quality of specialty Colombian coffee[J]. AIMS Agriculture and Food, 2023, 8(3): 789-803. doi: 10.3934/agrfood.2023042
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