What are the standard espresso parameters (dose, mass/volume, time, etc.)?

Question

I have a Breville Infuser espresso machine as well as a Breville Smart Grinder Pro. The espresso machine comes with two types of filters (for singles and doubles), and can dispense a pre-programmed volume of water corresponding to a single or double dose through its two front buttons (the machine also allows programming these volumes, if desired.)

Thus there are 4 combinations of coffee I could produce:

1. Using a single filter, and dispensing water corresponding to a single dose (~30 ml, as I understand).
2. Using a double filter, and dispensing water corresponding to a single dose.
3. Using a single filter, and dispensing water corresponding to a double dose (~60 ml, as I understand).
4. Using a double filter, and dispensing water corresponding to a double dose.

Are any of these 4 cases not usual or "recommended"? Particularly I never brew the combination corresponding to case 3.

What is the expected flavor profile of the espresso produced in each of these cases (more/less acid, sour, sweet, etc.)?

Which of these could be called a ristretto, normale, or lungo?

What parameters should I aim for in each of these cases, in terms of: mass of grounds in the filter before brewing (in g), shot volume (in ml) or mass (in g) in the cup, and extraction time (in s)? I have heard extraction times should be always 25 s regardless of the coffee dose and the volume of water, so 25 s for all combinations above.

This machine has a pressure gauge, indicating water pressure during extraction. Should I watch for a particular value in this gauge, or ignore it and just watch the extraction time? Currently my procedure for adjusting the grind is to make it coarser when pressure is in the upper 2/3rds of the gauge range, and finer when pressure is in the lower 1/3rd of the gauge range. I do not regularly monitor extraction time for adjusting the grind. Using combination 4, and adjusting the grind such that the pressure gauge stays close to the midpoint, extraction times are in the range of 25-30 s. However, using the same grind settings but dosing enough water for a single (combination 2), extraction times are closer to 15 s. To get closer to 25 s I would have to let the pressure gauge reach values way into the upper range.

In closing: although I enjoy the taste of combination 2, it appears most of the water stays in the coffee puck, and the volume actually dispensed in the cup is very small (about 15-20 ml). Perhaps I should reprogram the water volume to get something closer to, say, 30 ml? Would this help me get an extraction time closer to 25 s for this dose (assuming this is the "ideal" extraction time)?

Answer 1

The question is a very complex one, so I will try to answer with a standard approach of dialing in your espresso. Generally speaking what you should aim for is a espresso that is full bodied, sweet, fruity with crisp acidity, a syrupy mouth feel and an amazing aftertaste that stays with you long after you finished the cup. What you don't want to get are any sour (underextraction), bitter (overextraction), ashy flavors and a hollow aftertaste that leaves you wanting more.

You can get to that sweet spot different ways, using the single shot or double shot portafilter. There are some general guidelines though that you might want to follow.

1. Generally using a double shot porta filter delivers better results. You are more flexibel in adjusting the grind size for example. In basically all specialty coffee shops, double shot baskets are used for making espressos. Surely this has to do with efficiency as well, since you can make 2 shots at the same time. I would suggest you try to find the sweet spot with your combination number 4 (or number 1 if you really don't want any more than a single espresso).

2. The first thing you have to consider is your recipe. Using a double shot basket what you should aim for is a dose:yield ratio of around 1:2. That means if you start with 20g of coffee (in the double basket), aim for a 40ml yield (for a double espresso). A very common recipe would be to start with an 18g dose and aim for a 36g yield. That would be a double shot or two single shots. If you pull shorter you will get a ristretto (short espresso) and if you push through more water, it would be a lungo. The yield is not fixed, you may adjust it depending on the coffee and taste. It is just a basis for dialing in properly, a baseline.

3. Once you decided on a recipe you should lock in the dose. Changing the dose, changes everything else, so you want to keep it as consistent as possible. However the grams are not fixed and will change all the time. If you change the coffee type/brand/origin/roast etc. you will have to adjust again. Even variables such as temperature, humidity and how much coffee is in the basket above the grind chamber will influence your grinders behavior and therefore the dose. The only definitive remedy is weighing out every single dose and shot (for home use at least whenever you use new coffee to find a setup that delivers consistently good results with this brand or type, albeit it will not consistently be optimal).

4. Now that you have the dose and recipe fixed you want to get an extraction time of somewhere between 20 and 30 seconds. Adjust the grind size (keep in mind that your dose changes as well, when you adjust the size, since the grinder measures the time of grinding and not the weight of the coffee) so that you reach the desired extraction time with the given recipe. Don't overdo it though and stay in the espresso grind range.

5. Keep in mind that you tamp correctly. Level out the grounds before tamping with slight shaking, hitting the basket on the sides and using your fingers. Try to tamp as straight as possible, the distance between the basket and the edge of the tamper should be equal on all sides. A tilted puck will extract badly. You don't have to tamp terribly hard, just until you don't feel the coffee bed changing any more. Anything more is redundant.

6. Pull a shot, taste and reflect if the result is the coffee you want. If it is, good for you, most likely it isn't though and you will have to adjust again.

7. If it isn't the coffee you want, try to figure out what's wrong with it. Is it too sour? Probably underextracted. Try to grind slightly finer, so the extraction process takes a few seconds longer to get to the yield you want. Does it taste bitter and hollow? Probably overextraced, in this case do the opposite.

8. Forget everything of the above and follow your taste buds! If one or more of those things doesn't produce taste profiles that you like, just kind of ignore them and try something else.

This is a general approach of how to dial in your grinder and produce a nice shot. It is not the only one, it is definitely incomplete and it will not be able to replace experimenting and experience.

Also don't bother too much about the pressure at the beginning, try to get consistent results that you like when pulling shots and after a while you will learn and understand your machine better. Also don't forget to flush the group head and portafilter before use, so old coffee oils are removed and you get up to temperature.

Cheers.

Answer 2

I will try to enlist the basic parameters as far as I know. There may be some others that I could forgotten and they may be added later on.

• The volume seems normal in the default setting. A regular espresso is expected to fit in 25 to 30 ml range.

• The dose is expected to be around 6 to 8 grams per cup.

• The time or the speed of flow is expected to be around 1 ml per second. Therefore, 25 seconds for a 30 ml cup is quite normal.

• The tamping is done around 20 kgf downward force.

• The temperature must be in between 92 and 94 degrees Celsius.

• The pressure is expected to be 7 to 11 bar, where possible. Most of the household type espresso machines cannot produce such high pressures.

---

Now, the different types of beverages you can prepare with this device. I think this is the second but less relative part of your question. Actually, this is answered several times in Coffee SE.

• Ristretto is a beverage you prepare with the same amount of dose, but in half amount of water. So, the time should be 15 seconds with single dose basket.

• Normale is the standard espresso. Aforementioned standards apply. The first option of your machine.

• Lungo is the beverage with the single dose, double(?) the water. The third option might produce something similar to lungo. (Please see this discussion.)