Discrimination of Defective (Full Black, Full Sour and Immature) and Nondefective Coffee Beans by Their Physical Properties

2014 ◽  
Vol 37 (5) ◽  
pp. 524-532 ◽  
Author(s):  
Abebe Belay ◽  
Yirgalem Bekele ◽  
Ataklti Abraha ◽  
Dagne Comen ◽  
Hyung Kook Kim ◽  
...  
2020 ◽  
Vol 24 (1) ◽  
pp. 39-48
Author(s):  
Yishak Worku Wondimkun ◽  
Shimelis Admassu Emire ◽  
Tarekegn Berhanu Esho

AbstractEthiopia is known for its specialty Arabica coffees affected by mix-up. Physical and sensory properties of dry processed green coffee beans have been reported for the influence on the sensorial quality and coffee process optimization. The aim of this study was to investigate physical and sensory properties of sixteen varieties and to determine relationship of attributes. Physical properties of coffee beans were taken by measuring linear dimensions, densities and weight. Moreover, professional cuppers were analyzed sensory properties by using standard procedures. In this study, the longest (10.40 mm), the widest (6.82 mm) and the thickest (4.48 mm) varieties were Odicha, Feyate and Challa, respectively whereas the shortest (8.28 mm), narrowest (5.59 mm) and thinnest (3.52 mm) were 74110, Mocha and Bultum, respectively. The shape & make value of variety Bultum was “fair good” whereas variety Feyate was “very good”. Furthermore, the results of “shape & make” were significantly correlated with measured physical properties. The results indicate that most physical and sensory properties of coffee varieties have significant (P ≤ 0.05 differences. These properties were influenced by growing regions and variety difference. The outcome of this study can be used for coffee bean characterization and process optimization to improve beverage quality.


Author(s):  
Erick Baruch Estrada‐Bahena ◽  
Ricardo Salazar ◽  
Mónica Ramírez ◽  
Ma. Elena Moreno‐Godínez ◽  
Javier Jiménez‐Hernández ◽  
...  

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Ezana Getaneh ◽  
Solomon Workneh Fanta ◽  
Neela Satheesh

Optimum flavor and aroma of the coffee are developed during the roasting process. However, certain problems exist in the coffee roasting process such as partial charring, over roasting, and poor temperature distribution across the coffee bean (due to the low thermal conductivity of bean), if conditions are not optimized. Hence, uniform temperature distribution across the coffee bean in the roasting process is highly desirable. To achieve these requirements, the broken coffee beans were positioned in a single layer packed bed arrangement using the closed system by circulating hot air. In this experiment, three factors were arranged in a completely randomized design with three levels and three replications. The first factor considered was roasting temperature (200°C, 230°C, and 260°C), second factor was roasting time (5 min, 10 min, and 15 min), and third was particle size (4–6 mm, 2.36–3.35 mm, and 1.7–2.36 mm). The initial moisture content of raw beans (cv. Limu) was determined. The data were collected on selective physical properties of roasted coffee beans and sensory acceptability of prepared beverage. The results showed that the physical properties and sensory acceptability are significantly high ( P < 0.001 ). It depends on the interaction effect of all the studied factors. Among the studies parameters, roasting temperature of 230°C with a particle size range of 4–6 mm showed the steady transition in dry mass loss and change in bulk density with increase in roasting duration. Coffee roasted at 230°C for 10 min with a particle size of 4–6 mm showed the highest sensory acceptability score (89.21). In conclusion, it can be said that a temperature of 230°C, a time of 10 min, and a particle size between 2.36–3.35 mm and 4–6 mm are recommended conditions for the roasting process of coffee beans.


Author(s):  
Paulo C. Corrêa ◽  
Gabriel H. H. de Oliveira ◽  
Wander L. Vasconcelos ◽  
Guillermo A. Vargas-Elías ◽  
Fábio L. Santos ◽  
...  

ABSTRACT The determination of physical properties is an important factor in the design of machinery and the scaling of post-harvest operations. The present study evaluates the influence of the level of roasting and the size of grinding on the physical properties of coffee during storage. The following physical properties were evaluated: true and bulk density, and intergranular porosity. Raw coffee beans (Coffea canephora and Coffea arabica), hulled and dried, were roasted to two different levels: medium light (SCAA#65) and moderately dark (SCAA#45). The beans were then grinded into three different sizes: fine (0.59 mm), medium (0.84 mm) and coarse (1.19 mm). An additional coffee lot was kept whole. Following grinding, samples were stored at two different temperatures (10 and 30 ºC) and analyzed after five different storage durations (0, 30, 60, 120 and 180 days). The medium light roast had higher values for each of the measured physical properties. Finely ground samples had higher true and bulk densities, and porosities. It is concluded that the size of grinding, level of roasting and duration of storage significantly affect the physical properties of coffee.


2018 ◽  
Vol 112 ◽  
pp. 839-845 ◽  
Author(s):  
Jaime Daniel Bustos-Vanegas ◽  
Paulo Cesar Corrêa ◽  
Márcio Arêdes Martins ◽  
Fernanda Machado Baptestini ◽  
Renata Cássia Campos ◽  
...  

1976 ◽  
Vol 32 ◽  
pp. 365-377 ◽  
Author(s):  
B. Hauck
Keyword(s):  

The Ap stars are numerous - the photometric systems tool It would be very tedious to review in detail all that which is in the literature concerning the photometry of the Ap stars. In my opinion it is necessary to examine the problem of the photometric properties of the Ap stars by considering first of all the possibility of deriving some physical properties for the Ap stars, or of detecting new ones. My talk today is prepared in this spirit. The classification by means of photoelectric photometric systems is at the present time very well established for many systems, such as UBV, uvbyβ, Vilnius, Geneva and DDO systems. Details and methods of classification can be found in Golay (1974) or in the proceedings of the Albany Colloquium edited by Philip and Hayes (1975).


Author(s):  
Frederick A. Murphy ◽  
Alyne K. Harrison ◽  
Sylvia G. Whitfield

The bullet-shaped viruses are currently classified together on the basis of similarities in virion morphology and physical properties. Biologically and ecologically the member viruses are extremely diverse. In searching for further bases for making comparisons of these agents, the nature of host cell infection, both in vivo and in cultured cells, has been explored by thin-section electron microscopy.


Author(s):  
K.P.D. Lagerlof

Although most materials contain more than one phase, and thus are multiphase materials, the definition of composite materials is commonly used to describe those materials containing more than one phase deliberately added to obtain certain desired physical properties. Composite materials are often classified according to their application, i.e. structural composites and electronic composites, but may also be classified according to the type of compounds making up the composite, i.e. metal/ceramic, ceramic/ceramie and metal/semiconductor composites. For structural composites it is also common to refer to the type of structural reinforcement; whisker-reinforced, fiber-reinforced, or particulate reinforced composites [1-4].For all types of composite materials, it is of fundamental importance to understand the relationship between the microstructure and the observed physical properties, and it is therefore vital to properly characterize the microstructure. The interfaces separating the different phases comprising the composite are of particular interest to understand. In structural composites the interface is often the weakest part, where fracture will nucleate, and in electronic composites structural defects at or near the interface will affect the critical electronic properties.


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