What effect does defective beans have on coffee? Coffee Bean Defect Definition Coffee Main Defect Bean

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It is often seen that roasters bake coffee and baristas pick out some defective beans before brewing coffee, so what exactly are defective beans? What is the effect of defective beans on coffee?

First of all, let's find out what are the defective beans.

Common impurities in coffee beans:

1. Stone

Coffee beans dried naturally in the sun are likely to be mixed with pebbles, gravel, wood chips and other foreign bodies. Occasionally a piece of glass or coins will be found.

2. Cereals

Like stones, coffee beans that are naturally dried in the sun may be mixed with cereals or seeds such as corn, and pepper grains have been seen.

Common defective bean patterns:

1. Shell beans, broken beans

Beans that become shell-shaped because of developmental problems are called "shell beans"; beans that are damaged during treatment or transportation are called "broken beans", both of which can cause uneven baking.

2. Fermented beans

When treated by water washing method, polluting fermented beans are produced in the fermentation tank. Delayed processing or improper preservation can also occur after harvest, and beans will smell funny when baked.

3. Moth-eaten beans

Because pests such as coffee bark beetles lay eggs on coffee trees, and the hatched larvae eat coffee fruits to form cavities, which is the reason for the turbid or strange taste of coffee.

4. Moldy beans

Beans that are moldy due to incomplete drying, transportation or improper preservation will remain moldy even after baking.

5. Unripe beans

Beans harvested before the coffee fruit is ripe. Coffee mixed with unripe beans will have a strong fishy smell, giving off a disgusting, smelly smell.

6. Black beans

Beans that fall black before harvest, or beans that are completely fermented and damaged. It is the source of the foul smell and rotten smell of coffee.

7. Dead beans

Beans that fail to bear fruit normally will lead to weak flavor and strange taste of coffee. The color after baking is also not good, so it is easier to distinguish after baking.

8. Smelly beans

The beans are dried when the flesh is attached, or the flesh is not completely removed. Stinky beans give off the smell of iodine or soil.

9. Sheepskin membrane beans

Due to incomplete shelling and other reasons, the beans with residual endocarp are the reasons for the astringent or miscellaneous taste of coffee.

What is the effect of defective beans on coffee?

Dry incense: Tamiya model water-based solvent, tomato, choke flavor, medicinal alcohol, it seems to have a faint smell of corpse?!

Shixiang: I can't tell you the strange smell. It's a little sour, but it's weird.

Palate: salty and bitter

Defective beans not only make coffee taste bad, but also hurt the body, and may also cause damage to bean grinders and equipment.

In fact, after the seeds produced by healthy coffee trees are removed, they are washed, sunburned, fermented, dried and shelled. The whole post-processing process is flawless, and the color of coffee beans should be blue-green, light green or yellowish green, which are all healthy and delicious colors.

If there are other harmful colors or spots, it is a warning of defective beans. Because the precursor aromatic components of defective beans-protein, sucrose, fat, trigonelline and organic acids-are oxidized or eroded by molds and fungi, the color of the beans is strange, so since the chemical composition has deteriorated, the color and smell of the coffee will not be good. Drinking it may be harmful to your health.

Coffee production from cultivation, fertilization, irrigation, picking, peeling, fermentation, drying, shelling, transportation and other post-processing to storage process, are variables, a little carelessly will deteriorate into defective beans. According to the statistics of the International Coffee Organization (ICO), on average, about 15% of the defective beans in the world-black beans, fermented beans, mildew beans, moth-eaten beans, wilted beans, unripe beans, shell beans, shell beans, broken beans, floating beans, etc., will cause animal flavor, rotten fruit, bleached water, iodine, sour, potato, fishy, rotten wood and miscellaneous bitterness in coffee, and may contain biotoxins. It's bad for your health.

But you should know the difference between defective beans and beans of uneven size. Take Ethiopian coffee as an example, because of the variety, it seems to be of different sizes and even uneven roasting, which are normal and cannot be called defective beans!