How to identify and avoid buying defective beans? What is the effect of defective beans on baking?

As bean bakers, they all hope to buy suitable beans at the best price.

As we know, coffee raw beans can be divided into fine beans and commercial beans. How to make sure that you buy high-quality beans and how to select defective beans correctly?

1. Color

two。 Smell (coffee beans are at risk of absorbing odors when the water is dry)

3. Moisture: 8 to 13% moisture content is critical to the integrity of raw coffee-SCAA criteria: Natural process 10-13%; Washed coffee 10-12% (too high moisture: risk of mold or mold; too low moisture: risk of poor uniformity and loss of flavor). In addition, moisture can also affect the density of beans.

4. Density

5. Bean size: bean particle size also determines the price and value, and the uniformity of bean particle size is also very important for baked beans.

6. Treatment method

7. Storage or transport conditions: improper drying and storage of molds or molds that may cause odors

How to select defective beans:

All black bean

Whole sour bean

Fungal infection of bean

Desquamation is not enough.

Partial black bean

Sundries

Local sour bean

Locally infected bean

Pericarp

Fruit shell

Floating bean

Unripe bean

Withered bean

Light worm boiled bean

Severe insect damage

Dried gum fruit

shell

Damaged bean

Changes in baked beans

Generally speaking, baked beans can be divided into three stages: dehydration or frying, the chemical reactions that take place during baking and the physical reactions that take place during final cooling. Usually there are several changes in the process of baking beans, some can be observed with the naked eye, and some can not be seen with the naked eye.

1. Surface:

Color: green-white-yellow-orange; color difference darkens to brown when the temperature increases

Size: the water of the coffee bean evaporates during the baking process, carbon dioxide and other gases are discharged, the cell structure becomes more elastic and expands, and the raw bean size expands.

Surface: cracks and "blow holes" occur on the bean surface during the release of steam, and the water loss can be reduced by about 1%, while that of moderate baking is reduced to about 2-3%.

two。 Physical changes:

Temperature:

When the temperature reaches about 100 degrees, the beans begin to absorb heat, the water is being discharged, and the hot water is vaporized:

During the first explosion, the weight, gas and organic objects will change (for example, the first explosion will produce water vapor, the second explosion will produce carbon dioxide), the more air flow, the faster the heat conduction, the more hot air, the faster the heat conduction. Too much wind will increase the radiant heat, and the bean heart will turn black or not ripe in the middle.