Drip brewing, or filtered coffee, is a method for brewing coffee which involves pouring water over roasted, ground coffee beans contained in a filter. Water seeps through the coffee, absorbing its oils and essences, solely under gravity, then passes through the bottom of the filter. The used coffee grounds are retained in the filter with the liquid falling (dripping) into a collecting vessel such as a carafe or pot.
Paper filters (invented in Germany by Melitta Bentz in 1908) are commonly used for drip brew all over the world. One benefit of paper filters is that the used grounds and the filter may be disposed of together, without a need to clean the filter. However, metal filters are also common. These are made of thin perforated metal sheets that restrain the grounds but allow the coffee to pass, thus eliminating the need to have to purchase separate filters which sometimes cannot be found in some parts of the world. Additionally, many machines now use permanent plastic filters, which are made of a fine mesh. These of course add to the maintenance of the machine, but reduce overall cost and produce less waste.
Drip brewing is a widely used method of coffee brewing, particularly in North America owing to the popularity of domestic coffeemakers. There are, however, several manual drip-brewing devices on the market, offering a little more control over brewing parameters than automatic machines, and which incorporate stopper valves and other innovations that offer greater control over steeping time and the proportion of coffee to water. There also exist small, portable, single serving drip brew makers that only hold the filter and rest on top of a cup. Hot water is poured in and drips directly into the cup.
Brewing with a paper filter produces clear, light-bodied coffee, which is free of sediments, although lacking in some of coffee's oils and essences, which are trapped in the paper filter.[1] Among these are certain diterpenes that appear to increase risk of coronary heart disease. Metal filters do not remove these components.[2]
A less familiar form of drip brewing is the reversible or “flip” pot commonly known as the Napoletana.
3. Hand Drip Coffee