Post By E-Gene
GS3 pre-infusion setup comparisons
So over the weekend I went through about 700g of coffee just trying out all the different variables with my GS3, I was playing with temps and comparing shots. I then started tweaking the pre-infusion times that are pre programmable [I have the AV volumetric model]. I went thru so much coffee tasting that I actually started to forget the first few tests, silly me didn't start taking notes until halfway through the session!
I've ended up with a little sweet spot on the beans I've roasted (Brazils, guatemalans, yirgs, 10days post roast) which is Pre-infusion 4 sec on > 3 sec off > Pump engages for a 28-30 second pour [Timed from first signs of coffee flow] I have the temp set at 93.second crack and it's probably the best arrangement with this particular bean. This is based on a 21g LM basket with the doses being almost spot on, pouring 2 espresso at about 27ml each.
I'm just interested to know what other people have set their GS3's to and compare, maybe I missed something or can improve my shots. Particularly in regards to pre infusion.
Or do you totally disregard these functions?
I don't have a GS3, but (on an E61 Profitec 700 using the shot timer function) use a similar preinfusion process. My understanding is that the GS3 runs preinfusion with pump on/pump off. I preinfuse for 5 seconds, wait for first drops of espresso to hit the cup and then re-engage the pump for 23-27 seconds depending on blonding point. This style of preinfusion allows me to grind a little finer which, I think, produces more nuanced flavours in the cup as well as providing a little more body and viscosity.
I have GS3 but paddle version. So my preinfusion I do manual,by me .
I use around 5sec preinfusion time..but with some type of coffee - like Panama - I dont use preinfusion because taste with Panama with preinfusion somethimes is like to much cheery taste.
My temp of gs3 is 92.6C.
I'm pretty sceptical about the kind of pre-infusion you describe as having positive effects on coffee. It may lead to a different style of shot being tastier, ie ristretto might be more balanced but that might come at the expense of flavour clarity and body in your traditional espresso. (just an example, it might have other effects) The only way to really compare is to have two identically awesome baristas dial in the coffee to optimal taste, with and without pre-infusion and then choose which style one you prefer. Theres not really a right or wrong answer.
When you change something like pre-infusion you are also going to change the flow rate, which changes your extraction recipe The thing is though if you re-adjust your grind to make the recipe the same, you'll still be extracting the coffee differently because your grind is different.
With pre-infusion the coffee may taste best at 30gm out in 30 seconds, where as without it might taste better at 35gm out in 27 seconds. Who knows, you need to get your taste buds right around both methods and pull all kinds of shots ,shorter shots, longer shots, higher dose, lower dose, shorter time, longer time, to really be able to tell.
I've tried many variables with my GS/3 since I've owned it but the sweet spot for me much the same as you Brendogs. 93 degrees, 4-5 second pre infusion with a 25-28 second pour. Definitely dependant on the bean type though. I use a 21g ridgeless precision basket with about 23g of coffee. Seems to work well for me.
Now that I've plumbed my GS3, I've also started to have a play with pre-infusion settings. Honestly, I can't really tell the difference in taste between a pre-infused shot and a non-preinfused. I'm currently doing it, well, because I can! I find that with pre-infusion, it's a little more forgiving of poor/lazy tamping and distribution. Not really necessary if your technique is good. But like I said, it's a great little feature on the GS3 and I intend to keep using it.
Thanks. I was wondering if you are changing anything between preinfused and non-preinfused shots? The big difference for me is that when I do use my clunky form of preinfusion that I can grind quite a bit finer without choking the shot. The difference in grind then drives significant differences in flavour, acidity and mouthfeel for the shots.
Originally Posted by E-Gene
I think it's more the difference in grind that is changing the taste more than the pre-infusion itself. I think pre-infusion also just allows me to be lazier with my distribution and tamping.
You could drop into either LaMarzocco Sydney or Melbourne?
jump on the swift auto grinders so you can get 2 exact tamps and then run them through with and without pre-infusion...
They are really friendly and Ive found them quite helpful