Brewing Espresso

In this lesson we're going to go through the steps involved in brewing espresso.

Warming up

Miss Silvia is made with a heavy brass boiler, grouphead and portafilter that ensure even brewing temperatures when making espresso. However, all this metal takes a long time to heat up properly.

How to Warm up Miss Silvia

Turn on machine
Make sure there is sufficient water in the tank in the back of the machine and turn it on. We'll quickly want to move to priming or we may cause harm to the boiler.

Prime

It's important to prime the machine to ensure the boiler and plumbing are both full of water.
Step 1: place a large cup or pitcher under the steam wand
Step 2: turn the middle switch on the left to the on position, open the steam valve and wait several seconds until water comes out without a lot of air bubbles
Step 3: turn the steam valve off and quickly turn the middle switch on the left to the off position
Step 4: place pitcher under the grouphead and, turn the top left switch on and leave for a few seconds or until water comes out
The machine is now primed, and ready to warm up!

Insert portafilter
Begin the warmup process with the portafilter ready in position on the machine as this is part of the metal mass which needs to retain heat for the brewing process.

You'll also want to make sure the knob used for controlling steam and water is turned off to prevent any leaks. Many people have forgotten and returned to a flooded counter top.

20 - 30 minutes Later:

Grinding

Start the grinder - you want to grind only what is needed for the shot you are currently brewing, coffee when ground finely will quickly attract moisture and loose some freshness after only a minute. Before the grinder has finished, you'll want to move onto the next step and get Miss Silvia up to temperature.

Getting up to Temperature

Just before brewing we need to make sure Miss Silvia is at the right cycle with the boiler. Different than pre-heating, this step is done just seconds before brewing to ensure optimal temperature for brewing espresso.

Step 1: place a pitcher under the steam wand and open the steam valve
Step 2: turn the hot water switch to on and leave it on until the main boiler light goes on
Step 3: as soon as the light comes on - turn off the hot water button and shut off the steam valve
While waiting for the boiler to finish heating the machine, we move onto the next step - dosing!
Once the light goes back off, the machine is at the ideal temperature for brewing

Dosing While waiting for the machine to heat up, remove the portafilter from the machine, and dose the grounds into the filterbasket.

Leveling & Tamping

Leveling Leveling is an important step in the process to ensure grounds are packed evenly during the tamping process. Start by wiping the portafilter with your towel to dry the basket, fill with espresso grounds and level using your perfered leveling technique from the leveling lesson.

Tamping Now, tamp the grounds using your skills learned from the tamping lesson. When you've finished the final tamp, gently remove the tamper, and wipe excess grounds from the top of the filterbasked to ensure a proper seal between the filterbasket and the grouphead. An improper seal will prevent Miss Silvia from passing a full 9 bars of pressure through the grounds.
Insert the filled and tamped portafilter back into the machine, and turn until tight. The red dot on the grouphead should line up with the handle of the portafilter. If you are unable, or it is very difficult to turn the portafilter to the red dot, you might have too many grounds packed inside the filterbasket which will prevent a proper seal.

Espresso!

If you're quick and timed everything just right, the boiler light should be turning off just as you finish putting the portafilter back into the machine.

Press the brewing button to start running the shot.

Shot Timing

While you're learning, it's a good idea to time the espresso extraction because it will help you figure out if you are doing everything right. A 0.7 - 1.0 ounce espresso shot should take 20 to 30 seconds to extract, but since we're using the double filterbasket, you want 1.5 - 2.0 ounces of espresso in the same 20 to 30 seconds. Measure your shot to the top of the crema.

You should find that you are turning off the brewing switch just as the espresso coming out of the portafilter starts to lighten slightly.

If your shot takes less than 20 seconds to pour then you will end up with a sour underextracted shot. If the shot takes longer than 30 seconds the result will have a bitter overextracted flavour. Around 27 seconds seems to be the sweet spot with the beans we use, but it depends on your individual setup.

To correct the timing of your shot adjust the grind of your beans as discussed in the Grinding Basics lesson, adjusting finer to slow the extraction or more coarsely to speed it up.

A lot of people ask when do you start timing? There are two schools of thought on this. Some say you should start timing as soon as you flip the brewing switch (during the pre-infusion stage), while others go by when espresso first starts coming out of the portafilter. Both methods usually work out to around the same brewing time as the pre-infusion stage on the Silvia is around 5 seconds and usually someone timing from when the espresso first starts flowing until the last espresso drop will have a timing 5 seconds shorter than someone who starts timing right after flipping the switch.

Cleaning up

Remove the portafilter from machine, and use your knock box to discard the spent coffee puck.

Run some water through the grouphead and use it to rinse out the portafilter,
then return the portafilter to the unit so that it maintains temperature for the next espresso.
(video of cleaning the portafilter with water from the grouphead) ALREADY HAVE THIS