To tamp or not to tamp that’s the question. Well, not for much longer. Should you tamp the coffee grounds in a moka pot filter? Here’s what you need to know.
The coffee grounds in a moka pot should not be tamped down. Just scoop the grounds into the filter basket and distribute them evenly to create a flat bed that sits flush with the basket rim. Tamping down the grounds can result in bad coffee or even a moka pot failure in the worst case.
Why you shouldn’t tamp down the grounds and what can happen if you do? Keep reading to find out.
Should you tamp down coffee grounds in a moka pot?
The quick answer is; No, you shouldn’t tamp down the coffee grounds in a moka pot.
While a moka pot is often called a stovetop espresso maker, you shouldn’t treat it like an espresso machine. To make espresso in a ‘real’ espresso machine, the grounds do have to be tamped down. In a moka pot they shouldn’t be.
An espresso machine works under very high pressure. Pressures around 9 bar or even higher are common in espresso machines. That is a much higher pressure than you will create in a moka pot which will be around 2 bar.
Espresso machines are built to handle that high pressure and there are many safety mechanisms to keep everything safe. If you tamp down the coffee grounds, you need a higher pressure to make sure the water actually goes through the coffee grounds and brew coffee. In an espresso machine that is possible because it’s designed to create those high pressures. On the flipside, an espresso machine needs the grounds to be tamped down so you create enough resistance so this pressure can be created in the first place.
A moka pot is in no way designed or built to produce or withstand 8 bar of pressure. However, if you tamp down the coffee grounds, you create a lot of resistance for the water. A moka pot works at about 1.5 bar which means you can’t build enough pressure to get the water through the coffee grounds and actually brew coffee.
Let’s take a deeper look into what effects this can have.
What happens if you tamp down coffee in a moka pot?
There are a few things that could happen when you compact the grounds in a moka pot filter. Not all of them are disastrous but in none of the cases you end up with good coffee.
- The moka pot start leaking. The most likely thing to happen is that the moka pot starts leaking at the coupling of the boiler and collector. The place where you screw both big parts together is where you’re most likely to see leaks. Especially if you didn’t screw it on super tight and/or your silicone gasket isn’t in the best shape. If leaking out that way provides less resistance than going into the collector, that’s the way the pressure will go.
- The water channels through the grounds. Pressure will always follow the path of least resistance. If there is no way out, the steam will find a way or even make its own. One thing that can happen is that the steam channels through the grounds. Basically it digs a tunnel. Instead of evenly going through the grounds and thereby brewing coffee, it moves the grounds in one part of the filter basket and the steam all escapes through there. This way you actually get weak coffee because the pressure and steam escape without picking up much of the coffee on the way.
- The pressure will be relieved through the safety valve. If there is no way for the pressure to get out, at some point the safety valve will be opened. Steam will shoot out the little valve to prevent worse things from happening.
- The moka pot could explode. The safety valve is there to prevent this from happening but there are situations where it could malfunction. Maybe it’s stuck or maybe it’s too small to relieve the pressure fast enough. This can cause the pressure to get too high. Moka pots aren’t built to withstand super high pressures so what can happen is that the upper part blows off the lower part of the pot. You can imagine that when this happens the coffee won’t be the only brown substance being released in that kitchen…
Of course it also depends on how strongly you compact the coffee grounds. If you just tap it slightly, it’s very unlikely to cause any problems. However, if you tamp it down like you would in an espresso machine, you’re likely to run into one of the problems outlined above.
What if my moka pot coffee isn’t strong enough?
You might be tempted to tamp down your coffee grounds in your moka pot because the coffee you made last time wasn’t strong enough (for your tastes) and you want to get a stronger coffee out of it.
Then tamping down might seem attractive because;
- You can fit more grounds in the filter basket.
- You think the higher pressure will make for better extraction of the grounds.
I’ve already explained above why this approach isn’t a good idea. So what can you do to get stronger coffee from your moka pot?
In no particular order;
- Ratio: Lower the ratio of water to grounds. You want to keep the amount of grounds in the filter basket about the same. That means you can use a little less water for the same amount of coffee. Don’t go too low however. If you don’t use enough water it can be difficult to get the right pressure.
- Grind: How finely the coffee is ground has a pretty big impact on the final results. For a moka pot the grind should be a bit coarser than for an espresso machine. If you want a stronger brew, you can try a slightly finer grind. This creates more surface area on the granules which means you can extract more compounds from them. However, don’t go too fine because it could clog the holes in the filter.
- Roast: You can also try a different roast of coffee. The roast influences the taste and caffeine content of your coffee. However, roast vs. strength is not as straightforward as you might think. Check out this post for more information. What you perceive as “strong” could also be something different than the next person. So read up on the effects of roasting on the final product.
- Beans: If you really want coffee with a kick, try Robusta beans. Robusta tends to have a much bolder taste and almost double caffeine content compared to Arabica. On the flipside, the taste is not as clear and bright as a good Arabica. Give it a try. If you like it but it’s a bit too much, you can try blending Robusta and Arabica.
Favorite Moka Pot Products
You don’t need many things to brew good coffee with a Moka pot. Here are the few things you need to make the best possible coffee.
- Moka Pot: Just buy a high quality Moka pot from the get go. The cheaper ones can be messy when brewing. Bialetti is the original and still one of the best with it’s classic looks. They cost a bit more than the cheap ones but these can last for decades and the parts that wear out are easily available for the Bialetti Moka pots. The 3 cup size is good for a single person (Amazon)
- Beans: Good coffee starts with good beans. You can’t make bad beans taste good. Espresso roast beans are good for a Moka pot and will get you closer to that typical espresso taste. Peet’s coffee does a great 100$ Arabica espresso roast. Give it a try, you can get it here on Amazon
- Grinder: Using whole beans means you need to grind them at home. This improves the taste because the grounds are much fresher. A Hario Slim (Amazon) is a great starting point for the starting home barista. If you want a good hand grinder for a good price, check out the TimeMore C2 (Amazon)
- Scales: To get consistent results, a set of accurate scales is essential. Check out this Apexstone scale (Amazon). I’ve been using it for more than a year and while it doesn’t look the sleekest, it’s cheap and just as accurate as more expensive coffee scales. It just reacts a little slower.