Today one way valve talks about coffee extraction, there are four main aspects: the ratio of coffee powder and water, over extraction, insufficient extraction, and extraction time.
The ratio of powder and water means the ratio of coffee powder and water. It’s mainly to obtain the best flavor balance. Every gram coffee powder and every milliliter water are most crucial.
Extraction time means the fusion time between coffee powder and water, and it’s the most important variable factor for the good coffee. Others noun like brewing time or soaking time, they are also means extraction time.
Insufficient extraction means the fusion time between coffee powder and water are too short so that they cannot extract all the flavors from coffee powder, it will make you feel the coffee taste is too thin and unbalance bitterness. The others reason for insufficient extraction imputes for the coffee powder grinding too coarse or low water temperature. If the ratio of coffee powder and water are too high, you will get the strong coffee of insufficient extraction. This kind of coffee is not only lack of it’s feature, but also with bitter taste.
Over extraction means the fusion time between coffee powder and water are too long, or the ratio of coffee powder and water are too low. Using the drip coffee machine and brewing espresso, the coffee powder grinding too thin will result in over extraction. If brewing coffee by hand, it maybe causes by the long extraction time, and if water temperature is too high that will result in over extraction. In fact, over extraction will extract too much unneeded chemicals, such as caffeine, and also it will make coffee become bitter and unbalanced taste.