Tamping twice; short-duration shots

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javajeff

#1: Post by javajeff »

Hello,

Pretty new here. I have a Breville Barista Express that I was able to just pull my first half-way decent espresso with. The first 3-4 times I tried, the pressure gauge was basically zero'd, resulting in weak, bitter coffee. After doing some basic research, and finally weighing my grounds, I discovered that I only had about 12g in my double shot. After I upped that to 19g, the pressure showed in the normal range and the taste was much improved.

Couple of questions though:
- Is it ok to tamp twice? In order to get 19g of grounds into the little 54mm portafilter, I had to tamp once when it was initially full (12g), then add in more grounds till it was full again, then tamp a second time (19g total). I'm worried that I am over-tamping those first 12g. That worry was not abated when I went to throw away the spent grounds, either. The puck (although dry) was stuck in the portafilter and I had to basically dig it out with a fork. That doesn't seem normal. But wadda I know?
- The total duration of the shot was *maybe* 15 seconds, and the output volume was low. I understand I should expect it to be longer (25s), and more coffee. Anything come to mind about why I would experience this?
- I got the Breville used and it didn't come with that little "Razor" tool to level the grounds with. Is that worth getting? Or maybe something more like this?

Thanks in advance,

Jeff

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Jeff
Team HB

#2: Post by Jeff »

Tamping pressure, as long as adequate, should not significantly impact extraction pressure and ("if you have to ask") shouldn't be used to control extraction pressure or flow rate*.

Tamping twice runs the risk of cracking or otherwise disturbing the puck or its seal against the basket. It is hard to think of a situation where I'd recommend it.

It sounds like you're putting too much coffee in the basket. When tamped and locked in, there should be around/at least 2 mm of space above the puck and below the shower screen. One way to check this is with a coin like a US nickel (about 2 mm thick) on the tamped puck. If it leaves an impression after locking it in (dry), then you've got less than 2 mm of headspace above the puck.

If you're not getting sufficient pressure and have a reasonable dose in the basket, the problem is most likely the grinder or the coffee. If the coffee is reasonably fresh, then you're down to the grinder.

"Grind finer" is the first step

The internal grinders on the Breville are similar to the Smart Grinder Pro ("SGP"). You may need to adjust its burr with the internal setting. There are many videos of how to do this adjustment.

The "Razor" tool is, from what I can tell, intended for using pre-ground coffee with a pressurized basket. It likely should never come near a prepped puck for a conventional basket. In general, distributors make a puck look pretty, but aren't going to fix any distribution problems, just hide them.

* There was some use of "nutation" a while back in a barista competition. As I understand it, it was needed because of the rules of the competition and the desired output of a professional barista in that controlled, competition situation.

Nunas
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#3: Post by Nunas »

javajeff wrote:Hello,

Pretty new here. I have a Breville Barista Express that I was able to just pull my first half-way decent espresso with. The first 3-4 times I tried, the pressure gauge was basically zero'd, resulting in weak, bitter coffee. After doing some basic research, and finally weighing my grounds, I discovered that I only had about 12g in my double shot. After I upped that to 19g, the pressure showed in the normal range and the taste was much improved. Couple of questions though:<snip>
Jeff, the razor tool is not essential, nor is the cloverleaf distributor that you linked. I had the razor tool with some of my Breville machines and rarely used them after trying them out. Likewise, I have a similar cloverleaf distributor, which I used to use quite a bit; it now sits in the "spares" drawer. I suggest instead a dosing funnel. You may be able to make one up to test the concept using a single-serve yogourt container. I have a stainless one which I use daily, else I'd have coffee grounds all over the place. I'm not a big fan of double-tamping, as I believe that it can lead to inconsistent particle distribution. I used to do it and when I did, I only slightly tamped the first time, after giving the portafilter a few smacks to sort of settle the grinds. I suggest, instead, that you get a WDT tool, which is a handle with an array of tiny stiff wires; There are posts about them here on H-B, and you can see all sorts of examples on Amazon (both good and bad). Again, there's no need to fork out money at first; you can test this concept by going to the dollar store and buying some fine needles. Stick them into a wine cork, which will serve as a handle. Frankly, that's all I use, when I WDT, which BTW isn't often. I only use it when my grinds are a bit clumpy, which seems to happen with some roasts/coffees more than others.

As for timing, weighing your dose is the right thing to do. I weigh the dose and the shot (and the temperature of the milk when used) every time. In other words, I'm as consistent as humanly possible. Your remaining timing issue is simply a matter of balancing the time against the fineness of the grind and the dose. I'd suggest settling on a dose and then messing with the grind until you get what you like; then you can tweak the dose. Once you get dialed in, then it's just a matter of tweaking your grinder a tiny bit finer each day or two to compensate for the effects of bean aging.