What is the best water temperature for hand-brewed coffee? what is the taste of coffee with high water temperature and low water temperature?

With the arrival of the boutique coffee wave, coffee shops around the world are brewing coffee under an extraction framework that includes four basic elements, such as water temperature, powder-to-water ratio, grinding degree, and time.

Water is a very strong solubility of the substance, it as the main component of coffee, its main role is to dissolve the substance in the coffee particles into the water, the higher the temperature, the more intense the water molecules, the stronger the extraction ability, and vice versa. In the case of high water temperature, generally above 93 degrees water temperature, due to strong molecular activity, it is easy to extract most of the substances in the coffee particles, and the extracted coffee liquid is easy to bitter. At a temperature below 88 degrees, the activity of water molecules is weak, coffee substances are not easily extracted, and the overall coffee solution is an under-extracted state, so the ideal water temperature is between 89-92 degrees, adjusted according to the different roasting degrees of beans.