The causes of defective beans and how to affect the taste? What's the taste of defective beans?

The causes of defective beans and how to affect the taste? What's the taste of defective beans?

Yesterday we briefly introduced the defect requirements of SCAA (American Fine Coffee Association) for premium Arabica coffee beans. Today, we will introduce in detail the causes of various defective beans and how to affect the taste of coffee.

[all black beans / some black beans]

Introduction: raw beans with completely blackened internal or external surfaces are opaque black.

Cause: excessive fermentation caused by organic microorganisms.

Cup test performance: fermentation or smelly, dirty, acidity, mildew taste, phenolic flavor.

[whole sour beans / partial sour beans]

Introduction: fermented raw beans with light yellow or reddish brown as a whole.

Cause: fermentation caused by microbial infection in the process of harvest and treatment. The specific reasons may be: harvesting ripe coffee cherries or coffee cherries that fall on the ground; water pollution during processing; or coffee cherries hanging from trees in wet conditions over-ferment.

Cup test performance: according to the degree of fermentation, there may be odor, acidity, fermentation taste.

[fungal infection]

Introduction: raw beans with yellow or reddish brown because of mildew.

Cause: the temperature and humidity in the process of harvest and storage are suitable for mold breeding.

Cup test performance: may produce fermentation, mildew taste, dirty taste, phenolic flavor.

[foreign matter]

Introduce: foreign body other than coffee such as stone or branch.

Cause: it may occur in any process of raw bean processing.

Cup test performance: let the coffee lose its taste.

[dried coffee cherries / pods]

Introduction: some or all of the raw beans wrapped in black peel.

Causes: the pulp removal process of washing beans is incomplete or the treatment is not complete when the floating matter is removed by entering the water; the treatment of sun-dried beans is not in place in shelling or sorting.

Cup test performance: fermentation, mildew taste, phenolic flavor.

[serious worm-eaten beans / light worm-eaten beans]

Introduction: the worm gnawed out less than 3 (light worm boiled beans) or more than 3 (serious worm boiled beans) raw beans with a diameter of 0.3~1.5mm hole.

Cause: mainly affected by coffee worm (berry borer beetle).

Cup test performance: affect the appearance of ripe beans, may bring dirty flavor, Rio flavor, or mildew flavor.

[broken beans]

Introduction: broken raw beans or fragments of raw beans.

Cause: improper machine debugging in the process of raw bean treatment and pulp removal.

Cup test performance: soil taste, dirty taste, acidity, fermentation.

[uncooked beans]

Introduction: the silver skin is firmly glued to the surface of raw beans, and the bean body is sunken, small in size, sharp at the end, and slightly in the shape of a ship.

Cause: harvesting under immature condition.

The cup test shows that the taste of grass, straw and green astringency are the main sources of the astringency of coffee.

[atrophic beans]

Introduction: raw beans with wrinkles, small size and deformity like raisins.

Causes: insufficient water supply and excessive sunshine during development.

Cup test performance: grass flavor, straw flavor.

[shell beans]

Introduction: a shell with thin skin or an abnormal raw bean in the shape of an ear.

Cause: gene.

Cup test performance: scorched taste.

[floating beans]

Introduce: the raw bean that turns white or fades floats on the water because of its light posture.

Cause: improper storage or drying. Shell beans are left in the corner in a dryer or drying rack to form discolored, low-density beans. Or shell beans are stored in high humidity.

Cup test performance: there may be fermentation, straw flavor, straw flavor, soil flavor, mildew flavor, or it may dilute the flavor without letting the coffee lose its flavor.

[parchment shell beans]

Introduction: dried parchment is completely or partially wrapped with raw beans.

Cause: improper machine calibration in the process of treatment.

[bean shell]

Introduction: with dark pieces of dried fruit.

Cause: the sun-dried beans are not cleaned in the process, and the pulp removal machine is improperly calibrated.

Cup test performance: can bring dirty taste, soil flavor, mildew flavor, fermentation flavor, phenolic flavor.

[Quick beans]:

Introduction: it is not fully fried when baking, and the color is far lighter than other coffee cooked beans.