If we instead use weight then we would have a formula that would not change and a formula that can be consistant with different doses. I never got more into it than that, but then I saw a brillian post by AndyS on Home Barista with a formula that worked.

It’s very simple, we use brew ratioes in percentages, here’s the simplified formula:

• Ristretto:  100%
• Normal espresso: 50%
• Lungo: 33%
• Café crema: 14%
• Drip Coffee: 5.5%

Let’s use a normal espresso as an example, the formula says 50% so we measure by weight 18 grams of grinded coffee. Since it’s simply 50% the total weight achieved in 25-30 seconds would be 36 grams.

I tried a bunch of shots using this formula and damnit, it works. Now of course this, just like the golden rule is not something to be blindly followed, but used as a guideline it’s much better than the old golden rule.

It also allows us to communicate way better online. We can now simply use the brew ratio and much more closely replicate someone elses shots.

Source: Brew ratios for espresso by AndyS

I see so many vidoes of baristas doing stockfleths moves and whatever crazy distributions with thier hands wrapped around the portafilter. How do they do this without burning the hell out of thier hands?

Hmmmm…

Ever seen goldiggers from old movies? They shake the pan and heavier particles stay while lighter particles float away.

This is happening with blended beans to, so a blend conprised of say a mandheling and a monsooned malabar, the malabar will migrate to the top because it’s lighther. So after a while with no shaking to re-blend we have a blend where the bean percentages are way of and it will taste different.

Lovely eh? MORE variables hehehehe don’t ya love me?

The function of the over pressure valve is to release water back into the water tank when the pressure in the system rises above a set point.

When you brew a shot, watch the pressure gauge, it should hoover around 9.5 bar on most machines.

I like my over pressure valve to be slightly to high, around 11 bar. This is because the higher pressure keeps me on my toes.  See, if the over pressure valve was set to maintain 9-9.5 then I would never know if my grind was to fine except when I totally choked the machine. But with a higher pressure of 11 bar, now I have to adjust my grind or the shot will flow to fast. I can now also use the pressure gauge to see if my grind is on, when it is the puck will be the thing that maintains 9-9.5 bar, if I have to fine a grind the pressure gauge will tell me because it CAN go over the ideal 9-9.5 bar.

A slightly high pressure is all good as long as you only pull doubles (As I do), it doesn’t work if you pull ristrettos (Pressure goes to high) or singles (Pressure does not get enough resistance from the puck mass) It also only works on vibe pump machines, rotary pumps have a much higher throughput so the force is to high even for doubles.

If you have an overpressure valve, experiment by all means by going a little bit low or high, taste your shot as you might like it. High pressure tends to make the coffee a bit more sharp and bitter, lower pressure more crema and sweetness but also more acidity.

Excerpt from the Intruduction:

Some aromas that promise joy from a brewed cup of coffee elicit dread when smelled in a shot of espresso. Why do so many great brewed coffees taste awful as espresso?

The espresso community has long established rules about this. Roughly stated, coffee for espresso has to be low in acidity, not too lightly or darkly roasted, heavy bodied, and contain a significant percentage of dry processed beans. But despite everyone’s experience with spectacularly acidic or bitter shots, despite that Pavlovian anticipatory cringe every espresso hound has developed, there is no convincing logical reason for this.

Espresso is more concentrated than regular coffee; so strongly flavored coffees are said to become too strong as espresso shots. But the oils and crema of espresso buffer its extra strength. Moreover, the bad taste of these coffees done as espresso seems less about it being too strong, and more about being unbalanced. The explanation for the unsuitability for espresso of some great brewing coffees may not be in espresso’s strength, its extraction of lipids, or its creation of crema. Rather, it may be that espresso brewing extracts flavors differently, and alters their balance in the little cup. This paper tries to get some answers to what this difference is, how it occurs, and how it can be controlled.

Read the full article here:  SOME ASPECTS OF ESPRESSO EXTRACTION 

First look at the beans, more oily and darker than your current beans? Or lighter roasted? If the beans are darker, adjust your grinder 1 notch courser, if lighter 1 notch finer, that gets you in the ballpark.

Make sure your grinder is cleared of old stale grounds, clean it thoroughly because you don’t want old grinds messing with your measurements.

Now get out your measuring shotglass, (30ml or 60ml doesn’t matter as the timing needs to be the same) and your stopwatch.

Lock and load and start the extraction.

After 25.5 seconds stop the shot.

Evaluation time. If you got to much in the glass adjust your grind 1 notch finer, if to little, 1 notch courser.

Now it’s time to look at shot blonding, you want to reach those magic 25.5 seconds right when the shot starts to go blonde and look waterish, preferably right before this happens. A naked portafilter helps a lot here. By looking at the “crema cone” you can easily tell when the shot is about to go blonde. The stream will start out with a nice and fat cone, then about 5 seconds before blonding,the cone will collapse into an umbrella shape and that’s where you stop the shot, right before blonding where all that’s left is sour water. Remember that the golden rule (25.5 secons for 30/60ML) is not a rule at all, it’s a guideline, the real rule is looking for blonding and ultimately… how does the espresso taste?

An experiment that every home barista should try is to pull a shot, then as soon as the shot flows have a spoon ready and taste the stream every 5 seconds. This is realy an eye opener as you will now know exactly what each part of the shot contributes to the taste.

Many use “blonding” as a clue when to stop. My preferred way is looking at the crema cone using a naked portafilter. If you look at the stream it will start out with a fat cone once the shot gets going, then as soon as the coffee is spent and there’s little oils and flavour to extract the cone will collapse into an umbrella shape, that’s my clue to stop the shot.

When I was using blonding to know when to stop I would get the dreaded “white dot” in the crema in my cup if not overly cautious. After I started using cone collapse I never saw the dot again and my espresso tastes a lot better.

What’s your way?

Let your machine warm up for a while so it’s at correct temperature. Now without the portafilter locked in, open the water flow and listen. Hear that hissing sound? That’s superheated water, or the flash boil as some call it. Let the water flow until it stops and a couple moments more, that’s a cooling flush. Right after a cooling flush a HX machine is sitting around 206-207F at the grouphead, that’s why we want to bleed a little more water after the flashboil ends to get the group down to around 203F for a proper espresso extraction.

Steps to better espresso with the cooling flush: 

• Lock the empty portafilter into the machine.
• Listen for the flash boil to end and flush couple seconds more after it ends.
• Immidiately distribute and tamp the coffee that you already grinded, work fast as the machine will be up to temp again soon.
• Lock the portafilter in and pull your shot.

That’s it. The HX cooling flush is easy to work into your routine and will result in wastly better espresso.

If not, it could suggest that your grind could be a tad finer.

I’ll have to play around with that and see what effect this has.

Yes, it was not a dance on roses in any strech of the imagination, the Pavoni is bitching hard to learn how to use consistantly. It took me a month at least before pulling great shots with any kind of  consistancy.

If any of your parameters is even slightly off, your reward is a face turning sink shot for your troubles. Grind, distribution and tamp needs to spot on everytime, but after about 4-5 months I was pulling shots everytime that made people smack thier lips in anticipation.

All was not flowery though. After about 3-4 shots if you’r lucky the Pavoni heats up and needs rest, and there’s no steaming while pulling shots so you can forget about slinging a bunch of cappas or Lattes for the friends, it was upgrade time.

I got myself a Vibiemme Domobar Super after much research.

Having had the Europiccola it was a breaze getting up to speed on the Domobar. I wanted to check my shots so I modded the extra portafilter that came with the Domobar to be bottomles, or “naked” as it’s commonly referred to and was ready for the worst

To my surprise, my shots flowed perfectly. I already read up on the Domobar so I knew it likes a 16 gram dose for a douple. I distributed and tamped after adjusting my grinder to get a 25.5 second shot and had a look at the stream with baited breath…

The shots showed no signs of any problems, no donut extractions, no signs of channeling or premature blonding?

I have seen lots of people spending ages on getting a perfect naked shot, but I guess my time with the harsh mistress the La Pavoni Europiccola has been a great learning experience. I pulled about 30 shots of so by now with different blends of coffee and they all flow perfectly.

I can only conclude that some months with a manual lever machine is a great learning tool if you want to take your skills to the next level, or that the Domobar Super is very forgiving, but I don’t think that’s it because I have seen lots of naked shots on the net that are full of flaws.