Strietman brewing guide

First steps

When brewing with the Strietman CT2, you can safely ignore the commonplace ‘rules’ of espresso. Free yourself from thinking in terms of 15g, 92°C, and 9 bars of pressure, and you’ll find your coffee naturally improving. For instance, lighter roasts can benefit from temperatures of up to 96°C, and the total extraction time can even extend to one minute.

As such, the following information is intended as a rough guide. We encourage you to take your time and trust your senses. The CT2 is a fully manual machine. And you are the most important component.

Coffee beans

Whatever your taste preference, using freshly roasted coffee will produce the best result. Beans will taste best a week or two after roasting, and will lose most of their taste approximately two months later. We encourage you to buy your beans from a local coffee roaster so that you know they are fresh. Many speciality roasters will be investing in a sustainable supply chain and trade directly with the coffee producers. This means that everyone involved is paid a fair price for their work.

Grinder

Good espresso requires a good grinder. It’s important to grind your coffee right before you use it. Flat burr grinders are especially good at delivering an even grind, which produces a clean-tasting coffee. Large conical burr grinders create more variation in particle size. The additional fines will create a more full-bodied espresso and higher extraction yield. Whatever your choice, you will need to fine-tune the grind size to dial in your espresso.

Dosage

Depending on your filter basket, the maximum dosage is 15g or 18g of ground coffee. You may notice a light imprint of the shower screen on the coffee puck after the extraction has been completed. This indicates that you are brewing with the maximum dosage. Depending on the bean, grinder, and your own experience, you can adjust the dosage in small (around 0.5g) increments.

Grind

To extract as much flavour as possible from your coffee, you’ll want to use a relatively fine grind. This will increase the contact area, exposing more coffee particle surface to the hot water and making it easier to extract. It’s better to use slightly less coffee at a finer grind than a larger dosage with a coarser grind. If in doubt, try tightening your grind and reducing the dosage slightly.

Tamp

There is no ‘right’ way to tamp coffee. Some people compress the puck with their whole body weight, some use only the lightest touch to even out the surface. We recommend you start in the middle and experiment. When using the Strietman tamper, the top edge of the tamper base should be just below the rim of the filter basket after tamping down. The rest is up to you.

Pre-infusion

Preinfusion is one of the most important steps of the extraction process. With the Strietman CT2, you have an incredible level of control over your pre-infusion. Preinfusion starts when the hot water reaches your coffee bed. The ground coffee will swell and the first aromas will come to the surface. Lighter roasts benefit from a longer preinfusion time. This allows the individual coffee particles to swell slowly and evenly, helping to achieve an even extraction without channeling. Conversely, darker roasts favour a shorter preinfusion and extraction. Use a coarser grind with these to avoid unwanted bitterness.

Water

Espresso consists of 85% water, so it's essential to get this component right. Espresso favours water with some hardness, as the minerals will help to extract flavour from the ground coffee. But water with too much mineral content will cause excess scaling in your machine. As always, it’s about finding the right balance. A pH level between 7 and 7.5 is recommended.

To find out more about water quality and how to keep your machine free of scale, check our maintenance guide.

Brewing

Fill the boiler with filtered water.

Turn on the machine by flipping the switch, the white light will illuminate.

Set the boiler temperature and wait until the indicator light turns red. While the boiler is heating up you can grind your coffee, preheat your cup, and prepare the filter basket for extraction.

When the desired temperature has been reached, lock the filter holder into place and gently lift the lever arm upwards. Take 4 to 6 seconds to raise the lever fully. This will ensure no air is drawn into the chamber.

For light and medium roasts, slowly push the lever down until you feel resistance. Hold the lever in position for 8 to 10 seconds as the first droplets form on the bottom of the filter basket. This is the preinfusion – make sure to keep light tension on the lever during this stage. Then, increase your pressure to the maximum resistance. Try to maintain a consistent flow of coffee throughout the remainder of the lever’s journey down. You will notice that less pressure is required further through the shot. Be sure to take your time, the total extraction time can even extend to one minute.

For darker roasts, a shorter preinfusion is preferable. Push the lever down until you feel resistance, but only hold it in this position for around 3 seconds. Then immediately apply pressure up to the full resistance, pulling the lever all the way down. Stop the extraction after a maximum of 30 seconds.

Troubleshooting

Only adjust one variable at a time!

Extraction too fast?

Try a finer grind. Then gradually increase the dosage.

Extraction too slow?

Try a coarser grind. Then gradually reduce the dosage.

Espresso too bitter?

Lower the boiler temperature. You can also reduce the extraction time and experiment with smaller dosages.

Espresso too sour?

Raise the boiler temperature. You can also increase the extraction time and experiment with larger dosages.

Espresso too watery?

Try a finer grind and aim for a longer extraction.

There is no clear central stream of espresso during extraction?

This is called channeling. The pressured water searches for the path(s) of least resistance, and may flow unevenly through the coffee bed, compromising your extraction. When channeling happens, the extraction will turn lighter brown and watery, and you will notice it flowing more quickly. Splashes of coffee on the edge of the cup are a common indicator of this issue.

To avoid channeling, take care to distribute the grounds evenly in the filter basket. Tamp them down firmly and keep pressure on the lever arm at all times during the extraction. A longer preinfusion will also minimise the risk of channeling.

The lever goes down very easily and you get a small shot volume?

Be sure to take 4 to 6 seconds to raise the lever fully. This will ensure no air is drawn into the chamber.