How to judge the quality of coffee beans? How to tell if coffee beans are fresh?

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The judgment of the quality of coffee beans

Good baked beans have no color spots, and the heat is uniformly connected from the outside to the inside, almost no defective beans can be seen as a whole, incomplete baking, good expansion, and good-looking tone and gloss formed by firepower can be called good-quality baked beans. Coffee beans wrapped in soot during baking can be distinguished by their appearance because the black fine particles are attached to the beans, so that the surface of the beans will blacken and look dirty.

To judge whether the baking is good or bad, in addition to the method mentioned above, you can also use fingernails and knives to cut the coffee beans to observe its cross section, or grind a few coffee beans and spread them out to see if they have the same hue. Another way is to take out two or three coffee beans and bite them. If they are crunchy, they will crack as soon as they bite, and they will not only bite hard, but also contain the entrance. They will feel very fresh, and the bitter taste accompanied by the aroma will spread all over the tongue, which means it is a good baked bean. In addition, it is based on whether the aroma is reduced as the standard, because the aroma is the life of coffee, that is to say, how much the aroma disappears, it represents the deterioration of its quality.

The tasting life of light-roasted coffee beans is affected by the acid composition. If the freshness becomes worse and there is moisture during preservation, oxidation will bring a strong and unpleasant taste and smell, especially new beans. For the preservation of deep-roasted coffee beans, special attention should be paid to the foul smell and scorched smell caused by firepower, exhaust and cooling, and more attention should be paid to fat. The surface of deep-roasted coffee beans will ooze fat that can not be seen by shallow baked beans. If the preservation period is prolonged, the effects of sunlight and temperature will promote fat oxidation, making it produce a unique stench, and the sealed way is used to keep the coffee beans fresh. But this will cause the temperature in the container to rise, and such a vicious circle will promote its deterioration, and the rotten smell it produces can not be emitted because the container is airtight, and when filled with the container, it will strongly seep back into the bean, aggravating its deterioration.

Based on the point of view of oxidation caused by contact with air, vacuum packaging or filling with inactive gas (gas) is generally adopted, but no matter how well the packaging is done, we should pay attention to sealing the fresh coffee beans. In addition, with the sun and temperature conditions, keep them in a dark place as far as possible, and abide by the preservation period of these three items, there will be no problems at all.

The freshness of coffee beans starts when they are roasted.

Freshly roasted coffee beans will begin to exhaust for about 5 days. When the gas is completely discharged (about a week), the freshness of coffee beans will begin to decline over time.

Judging the freshness of coffee:

1. Oil output: shallow baking to medium baking, no oil can be seen; deep baking, the deeper the baking degree, the more oil. So if you see deep baked beans coming out of oil, please calm down, this is normal, but if you see it in shallow baked beans, then it is recommended not to drink.

two。 Aroma: freshly roasted coffee beans will have a strong aroma.

3. Foam: there is more or less unemitted gas in fresh coffee beans, so filter bag expansion is not to increase nitrogen, but to pack fresh beans.

When hot water is poured on the ground coffee powder, there will be foam on the surface, and the coffee beans will have some bubbles and grease as if they are breathing. This is why there is this step of steaming, which is to accelerate the exhaust of coffee powder and reduce the appearance of channel effect.

The coffee bag packaging of Qianjie coffee is a bag with an one-way exhaust valve to vent the air from the bag, because fresh beans will release carbon dioxide to vent the gas in the bag, keeping the beans fresh and reducing oxidation.

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