The truth that ordinary coffee makers don't want to tell.

The basic ingredients of a good cup of coffee are freshly roasted beans.

Once the coffee beans are roasted, the extremely important acidic fat and volatile fat in the coffee beans will change chemically once they come into contact with the air. The esters and aldolases in the aromatic compounds of coffee are the most volatile, which will worsen the taste of coffee. Not only is the volatile loss of aromatic substances, the oxygen in the air will also oxidize aromatic components, especially the oxidation of fat, resulting in the smell of decay.

Freshly roasted coffee beans usually have a life cycle of up to two weeks, and the aroma of coffee is easy to emit. Even in a coffee bag packed with an one-way exhaust valve, carbon dioxide from cooked beans can be discharged from the valve while outside air cannot enter, which is considered to be the best way to preserve it, which can be extended for up to a month. Because the coffee releases a lot of carbon dioxide within a month after it comes out of the oven, once the emission is finished, the flavor begins to decay and the one-way discharge valve cannot stop it.

Now it is all large-scale commercial baking, from the bean baker to the trader, then to the retailer (cafe), and then to your hand, I don't know when it is!

Sometimes you buy coffee powder directly for convenience. As soon as the coffee bean is ground into powder, the surface area of the coffee bean in contact with the air is several times higher than that of the original bean, and the decline rate of the coffee bean increases. What you buy and drink may only be the "mummy" of the coffee bean!

Bloggers sometimes see some cafes put the returned beans in glass jars for window display, and often bring them out to the guests speechless! The basic principle of keeping coffee beans fresh is to find ways to block oxygen, moisture, heat and sunlight. It is better to go to this kind of coffee shop less.