[Experiment] Pegasus 900n bean grinder grinding with or without pressure chamber difference

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What we share today is a Pegasus 900n flat cutterhead grinder, which compares the grinding effect with and without bean pressing (gravity-driven).

Bean grinder information:

Flat cutter head of bean grinder

Use:

Bean grinder: Pegasus 900N

Italian machine: Pegasus E78

Grinding scale: look at the picture below

In the experiment, each group was extracted three times in the same way, because there is no concentration testing instrument, so it can not provide three times of concentration comparison, only through sensory judgment, combined with export sense and time description.

The first group of experiments:

Grinding and extraction in the case of 400g Italian cooked beans in the soybean warehouse.

Extract three times:

Similarly, 20g powder is used to extract 40g liquid.

The time is 28s.27s.28s.

Palate: smooth and full

Flavor: black preserved fruit, black sugar, nuts, black skillful

The second group of experiments:

Use the bean warehouse switch to separate the beans between the bean warehouse and the knife head. Without the gravity push of 400g beans in the first group, when the interlayer holds about 30g beans, grind out 20g powder to extract.

This group is also extracted three times:

Similarly, 20g powder is used to extract 40g liquid.

The extraction time is 26s.27s.27s.

It smells sour at first.

Flavor: black preserved fruit, nuts, black skillful

Taste: strong sour taste in the mouth, irritation will be felt when you stay for 3 seconds, and the whole tongue will be a little shaved.

Comparison results:

Compared with the two groups, there is no change in flavor and time, but the taste difference is obvious, from the soft acidity and high sweetness of the first group to the acidity of the second group.

There is a small difference in the effect of the powder particles between the two groups because of the different grinding conditions. it is seen to the naked eye that the particles of the second group will be a little thicker than the first group (because the pictures can not be clearly seen, so they will not be posted). Here we have to review the cutter head. The upper and lower cutters of the flat knife are placed in a parallel manner, so the coffee beans need to rely on the force of rotation of the cutter to push the coffee beans into the cutter. Therefore, the weight of coffee beans placed on the cutter head directly affects the effect of grinding. In the second group, due to the push without weight, jumping beans appear in the process, resulting in uneven grinding particles, resulting in insufficient extraction. So much so that it makes a difference in taste.

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