Hello, Lawnet would like to answer as follows:
According to TCVN 4193:2014, green coffee must meet a number of technical requirements such as:
(1) Grading the quality of green coffee
Grade |
Type of coffee |
|
Arabica coffee |
Robusta coffee |
|
Grade 1 |
A118a |
R118a |
A116a |
R118b |
|
A116b |
R116a |
|
- |
R116b |
|
- |
R116c |
|
Grade 2 |
A214a |
R213a |
A213a |
R213b |
|
A213b |
R213c |
|
Grade 3 |
… |
… |
(2) Color: Characteristic color of each type of green coffee.
(3) Smell: Characteristic smell of each type of green coffee, no strange smell.
(4) Humidity: Less than or equal to 12.5%.
(5) Allowable ratio of mixed coffee in each coffee grade.
Type of coffee |
Grade 1 |
Grade 2 |
Grade 3 |
Arabica coffee |
Not mixing R and C |
Mixing with R ≤ 1 % and C ≤ 0.5 % |
… |
Robusta coffee |
Mixing C ≤ 0.5 % and A ≤ 3 % is allowed. |
Mixing C ≤ 1 % and A ≤ 5 % is allowed. |
… |
Note |
- A: Arabica coffee, R: Robusta coffee, C: Chari jackfruit coffee - %: Calculated as a percentage of volume. |
(6) Maximum allowable percentage of defect volume (errors, impurities) for each grade of coffee
(7) Maximum mass ratio allowed for certain defects.
(8) Minimum weight ratio on round hole sieve specified for each grade of coffee; the size of the sieve hole is specified in Appendix C
According to Appendix A TCVN 4193:2014, regulations on defects related to visible appearance are as follows:
- Black bean and partly black bean: coffee beans whose insides (endosperm) are partially or completely black
- Black-green bean: unripe coffee bean, often with a wrinkled surface, dark green or almost black color and silvery skin.
- Brown bean (“ardido”): Coffee bean whose inside (endosperm) has a color range: from light reddish brown, brownish black, yellowish green to dark reddish brown and dark brown
NOTE 1: When roasted and soaked, it often has an unpleasant sour taste (bad smell).
NOTE 2: This kernel should not be confused with the mink-colored silk-shelled kernel (“melado”), the kernel is normally green inside, shown on the surface by light scratches, and does not lose the flavor of the kernel. brewed coffee.
- Amber beans: coffee beans are amber yellow, usually opaque
- Immature bean; "quaker" bean: Unripe coffee bean, often with a wrinkled surface, light green or silvery green skin, cell walls and internal structure that are not fully developed
- Waxy bean: Coffee bean has a translucent waxy appearance and has a color range from yellow-green to dark red-brown, this color has become the most typical; Cells and the surface of the nucleus show disintegrated fibers
- Blotchy bean; spotted bean: Coffee beans are greenish, whiteish or sometimes have unusual yellow spots
- Withered bean: The coffee bean is wrinkled and light in volume
- Spongy bean: The coffee bean is very light (meaning that when you press your fingernail on the tissue layer, you will see a mark appear); they are usually whitish in color
- White bean: The coffee bean has a slightly white surface.
- Black kernels and partial black kernels:
Due to the Colletotrichum coffeeanum fungus or other types of fungi attacking the coffee cherries/beans while still on the tree and on the ground, causing disease (ulcers) to the coffee berries.
Other possible causes are:
+ There is a lack of carbohydrates in the kernel due to poor farming practices;
+ Ripe kernels/fruits are over-fermented by yeast/mold and then dried.
- Green – black filling:
Young kernels, affected by high temperatures
Young beans, affected by improper drying of parchment coffee and coffee cherries (drying on the field or mechanical drying), e.g. high temperature (no microbial growth)
- Brown filling
Brown kernels can result from excessive handling during fermentation; The cause of the sour filling is unclear
With "brown" kernels, it is believed that these are ripe kernels that are dying during the fruit's drying process, and are affected by molds afterward.
Likewise, overripe fruit can ferment during the slow drying process by leaving the layer too thick, causing the internal temperature to rise too much and killing the embryo.
This may be caused by mold accidentally fermenting on ripe or young fruit before drying.
This can also be caused by Antestia aphids or aphids attacking young fruit, or by over-ripe fruit and improper rubbing techniques, or by over-ripe fruit or by prolonging the drying time of ripe fruit.
Best regards!
Please Login to be able to download