How to make coffee drink bitterness? The latest study finds that the source of astringency is not tannin.

How to make coffee drink bitterness? The latest study finds that the source of astringency is not tannin.

New research shows that the astringency in coffee is mainly caused by quinic acid and gluconic acid, not tannin.

The chlorogenic acid in coffee is degraded into dicaffeoquinic acid by baking, which condenses the lubricating protein of saliva and produces a wrinkled astringency in the epithelial tissue. Although dicaffeoylquinic acid is bitter in the mouth, it is a powerful antioxidant and a good medicine for the treatment of AIDS and hepatitis.

In terms of species, Arabica coffee is less bitter than spirobusta beans, and defective beans can also bring bitterness and other defective flavors.

In terms of raw coffee beans,

In the case of raw beans, the factors that produce bitterness:

Raw bean varieties contain too much chlorogenic acid, Robusta and related hybrids, Coffee defect rate is high: moth-eaten beans, immature beans, coffee fruits are harvested before maturity.

The dryness of coffee is similar to eating raw fruits and vegetables, such as bananas, and the taste of the tongue is the same as that of the mouth. If the coffee is of high quality, it won't make you feel bad.

In terms of coffee brewing,

In the extraction, the number of stirring should not be too much. Moderate stirring can improve the extraction rate of coffee, if excessive stirring, it will cause excessive extraction of coffee, astringency will be produced. When cooking, the extraction time should not be too long. Unless after a series of studies, using special brewing methods, the total extraction time of coffee is best controlled within the recommended brewing time. If you want to avoid the strange smell when brewing coffee, you need to grasp the honey spot extraction of the coffee. The sweetness of coffee can balance the taste of coffee, enhance the taste buds' perception of the thickness of caffeine, and cover the defects of astringency.

In terms of baking,

Quick-fried roasted coffee beans in shallow beans are prone to astringent and metallic taste, because quick-frying will develop more dicaffeoyl quinine, which is also the main source of bitterness.

In the baking process, the smoke exhaust is not smooth or the air valve is too small, the taste of roasted coffee beans is easy to mix, not only astringent, but also accompanied by a strong sense of smoke.

After the beans are heated to a certain extent, the beans will begin to swell and explode to a certain extent, the first explosion will begin to enter different degrees of culture, different temperatures will produce different flavors, and the second explosion will enter deep carbon culture.

Very shallow roasted beans can also cause obvious astringency, some use shallow roasting to show the acid of coffee, and even rescue the beans before the end of an explosion, especially for high-hardness coffee beans such as Kenya, if you save the beans before another explosion, you can almost avoid a bad taste.

In the baking process, if the force is too strong, it is easy to produce astringent taste and raw bean flavor due to uneven "diplomatic endogenesis".

The dehydration period is too short, that is to say, the water is insufficient, the bean core is not ripe, and chlorogenic acid stays too long in the process of water decomposition, which will also produce excessive caffeic acid and quinic acid, thus dealing with the bitterness of the coffee.