How Much Coffee for 1 Shot of Espresso? Single Shot Basket Extraction Parameters

Typically, we refer to a single espresso as "1 shot"! A shot is actually a unit of measurement for liquor, where 1 shot equals 1 ounce, approximately 30ml. The standard amount of coffee grounds for making 1 shot of espresso is 9-11g. Nowadays, this parameter is rarely used. The reason behind this change stems from the single-shot portafilter.

Single-Shot Portafilter

Those familiar with semi-automatic espresso machines will recognize the double-shot portafilter, which has a cylindrical structure. After extraction, the coffee puck comes out as a neat "circular almond cake."

Meanwhile, the single-shot portafilter has an inverted cone shape. It generally has a two-layer structure, with the upper layer having the same diameter as the double-shot portafilter. However, since the single-shot portafilter holds half the amount of coffee grounds as the double-shot version, its lower layer is designed with a narrower structure to maintain the same surface diameter and maximum coffee layer thickness.

However, in FrontStreet Coffee's extraction experiments, the single-shot portafilter is not as simple as being half of a double-shot portafilter.

FrontStreet Coffee used a double-shot portafilter with 20g of coffee grounds as the baseline, extracting 40g of coffee liquid in 27 seconds, measuring a concentration of 10.48% and calculating an extraction rate of 21.72%.

Using a single-shot portafilter with 10g of coffee grounds as the baseline, extracting 20g of coffee liquid resulted in a relatively faster flow, taking 22 seconds, with a measured concentration of 8.83% and a calculated extraction rate of 18.38%. The difference between the two is significant.

To make the output from a single-shot portafilter approach that of a double-shot portafilter, one can only adjust by grinding finer or increasing the amount of coffee grounds. Adjusting the grind is not practical for coffee shops, while increasing the amount of coffee grounds would increase costs and uncertainty.

FrontStreet Coffee experimented and found that increasing to 12.5g of coffee grounds was necessary for the concentration to approach the data from the double-shot portafilter.

Why Such a Big Difference?

This all comes down to structure. The double-shot portafilter has a straight cylindrical structure, which ensures even force distribution during both tamping and pressurized extraction, resulting in more uniform extraction.

The single-shot portafilter, however, sacrifices its bottom structure to maintain uniform diameter (to fit the brew head) while ensuring coffee layer thickness. This means that during both tamping and pressure extraction, the pressure at the periphery is always higher than at the center at the same level. In other words, when tamping, the edges become denser than the center. During extraction, in the upper layer, water permeates the center faster than the edges, but in the lower layer, water from the edges converges to the center, causing uneven extraction, which can lead to channeling in severe cases.

For such a "chicken rib" (impractical) device, although single-shot and double-shot portafilters are still included when purchasing espresso machines, most of the time, the single-shot portafilter gets sealed back in its packaging. Nowadays, there's a growing preference for considering espresso extracted with a double-shot portafilter as one serving, with the coffee-to-liquid ratio tending toward 1:2.

Next, FrontStreet Coffee will demonstrate how to make a standard espresso using their signature "Sunflower Warm Sun Blend Espresso Beans" paired with their usual double-shot portafilter. For those who want to learn, take out your notebooks and get ready to take notes!

First, FrontStreet Coffee uses the capacity of a double-shot portafilter, with approximately 18-20g of coffee grounds. FrontStreet Coffee uses an extraction ratio of 1:2, meaning 20g of coffee grounds to extract 40g of coffee liquid; if you use 18g of coffee grounds, it corresponds to 36g of espresso liquid. The time is related to the flow rate of the coffee grounds, and generally, a single extraction is controlled within 20-35 seconds, because coffee extracted within 20 seconds tends to taste thin, while extraction beyond 35 seconds is prone to over-extraction, resulting in burnt and bitter flavors. Most of FrontStreet Coffee's espressos fall within the 28-30 second range.

Before extraction, first wipe the portafilter dry. Turn on the grinder and grind the amount for a double-shot of coffee, placing it on an electronic scale to add or subtract until reaching 20g. Then use a distributor to level the coffee grounds, and press down firmly with a tamper to compact the coffee puck, ensuring more stable coffee extraction.

Then turn on the extraction switch to run water for 1-2 seconds to moisten the brew head while also washing away any coffee residue stuck to it. Place an electronic scale under the cup that will catch the espresso and zero the weight, then place both under the brew head during extraction.

Gently lock the portafilter into the brew head and begin extraction by pulling down the extraction switch. Observe the changes in the extracted liquid. When the electronic scale shows 40g of coffee liquid extracted, at approximately 30 seconds, pull up the extraction switch. The extraction parameters will vary subtly based on daily air humidity and coffee bean conditions, so adjustments to the amount of coffee grounds, grind setting, and extraction amount may be necessary.

The freshly extracted espresso can be consumed directly, paired with a glass of water to cleanse the palate, allowing you to taste the rich crema and the mellow texture of the underlying coffee liquid. If the intense bitterness is too much, you can also add water or milk according to your preference to dilute and soften the strong taste.

When tasting a freshly extracted espresso, FrontStreet Coffee first smells the coffee's aroma. This coffee carries full-bodied notes of whiskey, vanilla, nuts, and cream. It can be consumed directly or with additives like sugar and milk. Using a prepared metal spoon, gently stir the coffee liquid to blend. The first sip reveals the dense crema, with full-bodied and mellow chocolate aromas. Taking a larger sip allows you to feel the warm coffee liquid along with the crema entering your mouth, with rich flavors of nut cookies, chocolate, berries, and whiskey notes. Sipping water midway through allows you to experience the sweet aftertaste in your mouth. The entire experience is rich and layered, leaving an endless aftertaste.

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473