Coffee Tampers: How to Get the Most From Espresso Machines

You may have noticed the barista at your favourite coffee house doing it; he or she grinds the coffee and dispenses just the right amount into the portafilter (the handle with the cup on the end that receives the coffee and attaches to the espresso machine). With me so far? Good.

Then what happens? The barista uses a plastic or metal device that looks a bit like an old fashioned rubber stamp and pushes it into the coffee. Or at least, they should!!!

This step is known as tamping. Tamping results in the coffee being pressed firmly into a condensed layer within the portafilter. If you don't usually do this when you are making coffee at home then this is a quick and easy way to greatly improve the quality of the coffee you produce.

So why does it make any difference?

It's to do with what happens when you attach the portafilter to the machine and turn it on. The water (as steam) will be forced through the layer of coffee that is sitting in the porta filter. It follows the path of least resistance; any unevenness in the layer of coffee provides a route for the steam to move through that bypasses a lot of the coffee that you have paid for and placed there so lovingly. What a waste!!

By tamping you foil the steam's sneaky attempts to find an easy way through; it has no choice but to work its way through all of the coffee. This way you maximise the potential of all of the coffee that you have placed into the porta filter.

So how do you tamp?

It's really quite simple and should only take 30 seconds. Once you've dosed the right amount of coffee into the portafilter, you are ready for the first tamp. Place the tamper (use a metal tamper; not a plastic one) on top of the coffee and press gently (apply about 5lbs of pressure). Once you have done this, you will notice that some of the grounds will stick to the side of the basket in the portafilter. Knock these back onto the tamped coffee by tapping the whole porta filter gently against your hand or something solid.

Finally, you need to apply the finishing tamp to incorporate these grounds into the tamped coffee mass. This time you can press much more firmly (apply about 30lbs of pressure). You can practice by tamping on some scales until you are comfortable achieving the right amount of pressure.

Make sure you tamp as evenly as possible. If you want you can rotate the tamper to give a smoother surface to the coffee.

And that's it! Your coffee is now properly tamped and ready to make you great espresso with a rich flavour and fantastic crema!