First, let’s talk about why single dosing into a Breville is not ideal. It isn’t designed as a zero-retention grinder, meaning that grinds have plenty of space to collect inside the burrs and grinding chamber. The result of this is that each time you grind you get some old grounds from last time you brewed mixed in with your fresh grounds.
From my experience, this exchange of grounds each time you grind is actually pretty consistent, allowing you to get out the same weight of coffee that you put in. But, having stale old grounds isn’t ideal when it comes to the final taste in your cup, or when switching between different types of coffee and grind settings.
Ideally, you would grind some beans at the start of each brewing session to flush out the old grounds… OR you can ensure that there aren’t and grind stuck in there in the first place!
Many high-end single dosing machine uses some form of bellows to make sure that every last ground leaves the burrs, and now, someone has fabricated a bellows set that fits the Barista Express, Barista Pro, Barista Touch, and Smart Grinder Pro.
Two or three pumps using these bellows was all it took to drastically reduce the amount of trapped grinds withing the burr assembly
Take a look at the impact it had over a 10 shot sample. When compared to the regular hopper, the retention dropped from 1 gram, all the way down to an average of 0.2 grams. Equally as shocking was that one dose with the regular hopper held back a whopping 1.8 grams!
If you already use a single dosing workflow on your Breville, or if you’re interested in starting, this single dosing hopper is a necessity. Not only because it ensures accurate doses, but also to guarantee you’re only getting fresh grinds in your dose each time you brew.