When we hold our Intensive Espresso Training Classes, one of the exercises we always conduct is something called “Fractionation.” We use this to demonstrate the ideal size of an espresso shot.

HOW FRACTIONATION WORKS:

We start by dosing a portafilter with enough ground coffee to produce a double-shot. We then tamp, lock the portafilter into the group head, and initiate the shot (using the “continuous flow” button, if we’re using an auto-volumetric machine).

Instead of having the espresso accumulate in a single cup, we line up six glasses. In the first glass, we let half an ounce collect. Then, we slide it to the side, put in place the second glass, and let another half-ounce collect. We continue to do this until we’ve extracted three ounces of espresso into six glasses.

Once we’ve complete the espresso extraction, we then taste the espresso in each glass starting with the first drops (which fell into the left-most glass in the above photo) and continuing to the right until we’ve tasted the last drops (in the right-most glass).

Note the color of the liquid in each glass. That may give you an indication of what you will taste.

THE TYPICAL FINDING:

When we conduct this experiment for cafe owners/baristas that take our class, they invariably discover the following:

• Glass #1 (the left-most glass in the photo): Very sweet. Heavy mouthfeel.
• Glass #2: Sweet. Good mouthfeel. 
• Glass #3: Bitter. Some depth of flavor. Not watery.
• Glass #4: Very similar to Glass #3.
• Glass #5: Very bitter. Weak. Watery. 
• Glass #6 (the right-most glass in the photo): Even more bitter. More watery.

“Yuck,” is a common description for Glasses #5 and #6.

THE TAKEAWAY: LESS IS MORE

Most cafe owners/baristas will find that once a double shot exceeds two ounces, it becomes unpleasantly bitter. Extracting more espresso just waters down the sweetness, reduces mouthfeel, and adds more bitterness. 

Try this with your own espresso blend. With few exceptions, the ideal shot size for a blend will be two ounces, if not shorter than that.

With our own Malabar Gold Espresso, for instance, we typically pull double-shots that are roughly 1.5 ounces in volume. We find that shots at this size deliver a delicious mix of sweet and bitter accompanied by a creamy mouthfeel. 

*LEARN MORE: Visit the Educational Resources section of our website.