Coffee tamping is an essential part of the espresso making process. Along with other important variables including the grind, tamping can make or break an espresso. The aim of espresso tamping is to produce a compacted coffee pellet through which water from the traditional espresso machine can penetrate evenly. It is imperative that water is able to evenly permeate the coffee for optimal extraction. An uneven tamp will result in uneven extraction.
Once you have dosed the coffee grounds from your commercial coffee grinder into the porta filter gently shake the group handle to distribute the coffee grounds more evenly. Hold your espresso tamper so that the base of the handle is in the palm of your hand. Keeping your wrist straight, place the tamper into the porta filter and apply 5 pounds of pressure. Some of the grounds will have stuck to the sides of the filter basket therefore gently tap on outside of the porta filter using your tamper to release the grounds onto the flat pellet formed. Now you need to finish the tamp; place the tamper into the porta filter and apply a further 30 pounds of pressure, then polish the surface of the tamped coffee by rotating the tamper 720° in the porta filter. You should now have an even flat pellet of coffee ready for extraction.
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