Written 2002-03-22
Updated 2007-03-17, 2006-04-04, 2004-02-11
This document was written for owners of the Rancilio Silvia espresso machine and the Rancilio Rocky coffee grinder, but anyone may find it of interest.
Prospective buyers should refer to the following articles to learn about the relative merits of the Silvia machine:
Silvia is a pump-driven semi-automatic espresso machine. Make sure you understand what this means. You will need to budget enough money for additional accessories, specifically a good grinder, but also fresh coffee beans, cleaning supplies, etc. Read the Home Espresso Machines FAQ before opening your wallet:
IMPORTANT: Don't bother buying Silvia without a good grinder. This is the single most important lesson one can learn. Many people, including I, have made the mistake of trying to use Silvia with pre-ground coffee, a "chopper" blade grinder, or a cheap burr grinder. It doesn't work, and you'll soon learn why. The grinder, not the espresso machine, is the most important piece of equipment you'll buy.
For the most part, it is assumed that the reader is aware of the overall espresso process (grinding, dosing, tamping), related terminology (single, double, ristretto), and judging good espresso (color, crema, texture, volume, flavor, etc).
The secret to making espresso is achieving the proper rate of extraction of coffee. Your goal is to continually monitor the rate of extraction and adjust your technique to compensate for external factors (equipment, beans, environment).
How do you control the rate of extraction? The variables within your direct control are the grind, dose, tamp, and pull. Any of these variables can affect the rate of extraction. To produce consistently good espresso, you must keep the dose, tamp, and pull constant, adjusting only one variable—the grind—as needed.
Cheap coffee grinders are not able to grind finely nor consistent enough for high-end espresso machines such as Silvia. A fine grind means small enough coffee particles to expose the right amount of surface area per particle, as well as high enough density between particles. A consistent grind means precision in the amount of surface area per coffee particle. Cheap coffee grinders do not offer you, the barista, enough control over either variable. Without such control, you will have no control over the rate of extraction—the most important principle in making espresso.
Dosing should be as consistent as possible. The easiest way to do this is to overfill the portafilter, then level with a straight edge, such as the handle of the included plastic scoop. Be careful not to pack the grinds in any way; this causes inconsistent dosing.
With the standard Silvia single portafilter, this procedure may result in too much coffee. You may need to use a slightly less-than-level amount by sweeping a slightly bent finger or the curve of a butter knife across the top of the grounds. Again, your procedure should be as consistent as possible across doses.
It is generally easier to get better results with the double portafilter than the single portafilter. Some use the double portafilter exclusively in favor of the single portafilter.
An ideal dose should fill the basket, but still leave a tiny bit of room under the screen for the coffee to expand during preinfusion.
Like dosing, tamping should be as consistent as possible. The generally accepted level of tamping is 30 lbs. A bathroom scale can be used to confirm your technique. Although tamping can be used in a pinch to compensate for improper grind (too coarse or too fine), it is preferable to keep the tamp consistent and adjust the grinder than vice versa.
The included Silvia tamper is plastic and too small. A stainless steel 58 mm tamper is recommended.
An additional issue is the consistency of water temperature. Unlike with commercial espresso machines, which tend to maintain stable boiler temperatures, the boiler temperature of machines such as Silvia can vary when not brewing. (The Rancilio Silvia does keep a remarkably consistent water temperature when brewing.) A technique known as temperature surfing has been developed to ensure consistent brew temperatures.
The key to making good espresso is achieving the proper rate of extraction, i.e. the volume and the timing. The exact definition of this varies from person to person, as well as region to region. Below are some guidelines for a single shot; remember, the ultimate definition of "good espresso" is your own.
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Espresso (Normal) |
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Ristretto (Short) |
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Lungo (Long) |
The rate of extraction stays the same whether your pulling a single or double shot. Mark Prince explains:
"How can that be? It's mainly in the filter baskets used to pull a double vs. a single. Take a look at them - you'll see that the single basket is shaped differently, and the surface area of the "filter" part is roughly half that of a double basket. This smaller filter area ristricts the flow of espresso, so that brewing with a single basket means your flow through rate is reduced. And it's reduced roughly by half."
Judging espresso:
The ideal froth is known as microfroth: creamy texture with a shiny surface and no perceivable bubbles. It takes a while to get good, but it becomes much easier once you understand the process.
Two main factors influence the amount of steam you get. You want 1) the maximum boiler temperature, and 2) the right balance of air vs water in the system. For maximum temperature, start steaming immediately before the boiler light turns off. For me, this happens about 3.5 to 4 minutes after turning on the steam switch. (The temperature is lowest when the orange light turns on, and highest when it turns off.)
Too much water in the pipes means less room (and lower temperature) for steam, or steam that's too "wet." Too little water in the pipes means not enough water vapor to make steam. While waiting for Silvia to get to temperature, "bleed" the pipes every minute or two, i.e. open the valve for a few seconds to let out the water. The goal is to have "dry" steam when you start steaming.
The ultimate goal is to be able to create latte art.
This chapter describes how I make a latté every morning, starting with a cold machine.
Ground coffee is only fresh for a few minutes, before the volatile flavor oils evaporate. Roasted coffee beans last a week, and green coffee beans last for three years.
The tamping technique they use at Global Blends (Mountain View, CA) goes like this: tamp, tap the side, tamp again, wiggling gently north, south, east, west, then spin and polish. Tapping the portafilter settles the coffee but causes the puck to loosen from the sides, allowing water to bypass your coffee, so make sure you follow it with a good tamp to reseal the edges.
This technique is from Mark Prince's "Cheating Miss Silvia."
The pull should appear creamy and thick and straight, as honey would flow. If it gushes out fast as a brown liquid, you didn't grind fine enough, you under-dosed, or you used stale beans. If it barely comes out, you ground too fine, or you over-dosed the portion.
If you're only making espresso, skip this section.
While most guides say start 100°F, I start much earlier, on the advice of the proprietor of Global Blends. It does indeed work much better.
While most guides say start 100°F, I start much earlier, on the advice of Global Blends. It produces a "wet" froth which is essential for making latte art. You also need a pitcher with a pointed spout, not rounded lip, and a real latte mug (semi-spherical), not a coffee mug (cylindrical), so that the milk can roll in from the bottom.
Italians drink lattes and cappuccinos only for breakfast.
Additional resources:
Updated April 4, 2006: Wes S. wrote to me about reversing the order. I would like to hear from people about their experience with this method.
Updated March 17, 2007: I've tried this, and I think it's better for the espresso to wait for the milk than vice versa, since the frothed milk tends to settle.
From: Wes S
Date: söndag 2 apr 2006 21.01.00 GMT+02:00
Subject: Silvia question
All the walkthrough for making milk-based drinks with Silvias I've seen do it in this order:
* Pull the shot
* Steam the milk, clean the wand, and run some water through it
* Combine them
However, in the case of a latte, this seems to leave the espresso sitting in a cup, reacting to the air, for two minutes or so, which is also widely cited as degrading the flavor.
What is the objection to reversing the order?
* Steam the milk, clean the wand, and run some water through it
* Pull the shot (and immediately deploy it in the milk)
* Combine them
Since steaming temp is higher than brewing temp, the process of cleaning the wand should help lower the boiler to brewing temp anyway, suitable for the shot, and this way you get to combine the espresso and the milk immediately.
Wes
