Engineering Properties of Coffee Beans from Various Colors of Coffee Cherries

Yuwana, Yuwana; Silvia, Evanila; Bosman, Sidebang

doi:10.1016/j.aaspro.2015.01.052

Cited by 10 publications

(14 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The coffee beans tend to the spherical shape by increasing moisture, causing a slight increase in the sphericity (Equation 6), as shown in Figure (between 0.827 ± 0.009 and 0.842 ± 0.007). The operational sphericity (Mohsenin, ; Wadell, ) of the coffee beans (Equation 3) were between 0.695 ± 0.009 and 0.732 ± 0.007, which approximate to the values obtained for the coffee bean by other researchers (Afonso Júnior et al, ; Belay et al, ; Dias, ; Yuwana, Silvia, & Sidebang, ). The effect of moisture on the dimensions and on sphericity of coffee beans were best described by the power law model (Equation 13; coefficients on Table ).…”

Section: Resultssupporting

confidence: 77%

Diffusion of water and caffeine in coffee beans using the hemispherical geometry approach

Huamaní-Meléndez

Darros‐Barbosa

2018

J Food Process Engineering

View full text Add to dashboard Cite

Geometrical, morphological, and shape factors are crucial for the accurate prediction of mass transfer rate of caffeine and water in the extraction of caffeine in aqueous medium from coffee beans. A new expression for the sphericity was deduced considering the hydrated coffee bean as a triaxial semilipsoid with moving boundaries applied to a nonsteady state analytical solution to describe the diffusion phenomena for the hemispherical geometry to best represent the morphology of the coffee bean during the caffeine extraction at varying temperatures from 30 to 60 °C. The sphericity increases with moisture in a power law trend. The hemisphere mathematical model presented an excellent adjustment to the data, with diffusion coefficients between 1.03 ×·10−11 and 9.00 ×·10−10 m2/s for caffeine and 0.69 ×·10−10 and 2.03 ×·10−10 m2/s for water; strongly influenced by temperature with activation energy of 59.93 and 41.24 kJ/mol, respectively, for caffeine and water. Practical applications The decaffeination of coffee beans satisfies an important segment of the coffee market. Currently, many industries use the decaffeination technology based on organic solvents; others extract caffeine in aqueous medium and on a smaller scale the supercritical fluid extraction process. The present research provides important properties and a mathematical model to better represent the mass transfer phenomena, with the associated diffusion coefficients, along with a suitable expression for the size and shape of the coffee beans changing with the process, which can be used for the proper and accurate design and control of the extraction process. The proposed model used the hemispherical geometry approach with a reduced number of variables (e.g., only one equivalent radius), unlike other approaches that need three dimensions to represent the coffee bean size and the associated shape factor, which makes it time consuming, requiring more complex calculations, and not necessarily more accurate.

show abstract

Section: Resultssupporting

confidence: 77%

Diffusion of water and caffeine in coffee beans using the hemispherical geometry approach

Huamaní-Meléndez

Darros‐Barbosa

2018

J Food Process Engineering

View full text Add to dashboard Cite

show abstract

“…A esfericidade operacional segue o mesmo comportamento (Equação 7, com R 2 = 0,996) com valores entre 0,695±0,009 a 0, 732±0,007. Resultados aproximados aos obtidos por Yuwana et al (2015) com esfericidade operacional entre 67,8 a 69,1 para grãos de café com 12,2% de umidade em base úmida. Belay et al (2014) encontrou valores entre 0,67 a 0,64 para grãos de café com 10,22% de umidade em base úmida.…”

Section: Resultsunclassified

“…Pela dificuldade em determinar com exatidão a área superficial da partícula por apresentar irregularidades na sua estrutura, Wadell (1933) introduz um conceito de esfericidade operacional (Equação 2) que é amplamente usada para definir a esfericidade dos grãos de café e outras partículas. Consiste na relação entre o volume do sólido e o volume de uma esfera que possui diâmetro igual ao diâmetro principal da partícula de modo que possa circunscrever a partícula (BELAY et al, 2014;MOHSENIN, 1986;SEVERA;BUCHAR;NEDOMOVÁ, 2012;YUWANA;SILVIA;SIDEBANG, 2015), considerando o grão de café como um elipsoide triaxial pode ser representada pela Equação 3.…”

Section: Introductionunclassified

Efeito Da Umidade Nos Fatores De Forma Dos Grãos De Café / Effect of Moisture on Coffee Bean Shape Factors

Huamaní-Meléndez

Condori

Barbosa

2021

BJD

View full text Add to dashboard Cite

RESUMOO conhecimento dos fatores de forma dos grãos de café apresenta importância nos processos que envolvem transferência de calor e/ou massa como o torrado, a umidificação ou descafeinado, além de outras operações unitárias como a fluidização ou transporte pneumático. A modelação destes processos envolve o conhecimento do grau de aproximação dos grãos para uma forma geométrica regular, sendo a esfericidade a ferramenta mais usada para este propósito, modelando grande parte dos processos sob a consideração que o material pode-se modelar como uma esfera. No entanto, a dificuldade de calcular a superfície do grão de café, faz com que os pesquisadores adotem a esfericidade operacional para obter um valor de aproximação à esfera. Isto motivou para deduzir uma expressão para a esfericidade do grão de café baseado em que a sua forma aparenta ser um semielipsoide triaxial. Observou-se que as dimensões do grão de café e a sua esfericidade aumentam conforme aumenta a umidade dos grãos correlacionando-se ao modelo da Lei da Potência.

show abstract

“…The mean weight of a coffee bean or cherry [20] can be determined by weighing 1000-beans of a selected sample [21,22] with replications [23,24] using a digital balance with 0.0001g accuracy [7,20,25,26]. The bean screen having specific holes of 14/64-inch [20,25], and sieve number 19 [22] is generally used to determine the percentage weight of each variety [20]. To calculate the corresponding volume of green coffee, Eq.…”

Section: Weight Volume Density and Shell Contentmentioning

confidence: 99%

Physical and Mechanical Properties of Coffee Cherries and Beans in Africa: Review and the State of Arts

Bizimungu¹,

Ahouansou²,

Semassou³

et al. 2022

fst

View full text Add to dashboard Cite

Coffee is an important source of income for African smallholder farmers. The world is predominated by three coffee varieties, namely Arabica, Robusta, and Liberica originated in the African countries. However, the low coffee quality attributes can affect the coffee beans" price due to the improper post-harvesting processes. Therefore, this work is aimed to review the physical and mechanical properties of the African coffee cherries and beans on the country-wise level, and review the methods used to measure quality parameters and compare the key coffee quality parameters. This work was qualitatively conducted using secondary data on African Arabica and Robusta coffee from journals, conference proceedings, and reports. Methods used for determining the coffee beans" properties were explored country wise. The coffee attributes of the two coffee varieties were compared through statistical analysis using ANOVA. The review found that the coffee quality depends on geographical characteristics, agronomic factors, and post-harvesting processes. The coffee cherries de-pulping process is linked to the coffee quality to avoid the damage of parchment coffee beans based particularly on the size and shape of coffee cherries and beans. The analysed quality parameters showed that the Ethiopian Arabica coffee beans were larger than the Ghanaian Robusta coffee beans. While the size of Robusta coffee in Eastern African countries, particularly Uganda, is bigger than those in Western countries, especially Ghana. Therefore, the information on the coffee quality attributes can help to improve the performance parameters of the coffee de-pulping machine and enhance the price of African coffee.

show abstract

Engineering Properties of Coffee Beans from Various Colors of Coffee Cherries

Cited by 10 publications

References 8 publications

Diffusion of water and caffeine in coffee beans using the hemispherical geometry approach

Diffusion of water and caffeine in coffee beans using the hemispherical geometry approach

Efeito Da Umidade Nos Fatores De Forma Dos Grãos De Café / Effect of Moisture on Coffee Bean Shape Factors

Physical and Mechanical Properties of Coffee Cherries and Beans in Africa: Review and the State of Arts

Contact Info

Product

Resources

About