Rancilio RS1 Espresso Machine Review. Temperature profiling is now a thing

Rancilio RS1 espresso machine


The new RS1 from Rancilio Specialty promises cutting edge brewing technology & advanced temperature profiling. We put it to the test to find out if it delivers the goods.


Welcome to the Rancilio RS1

If you used the RS1 without knowing who made it, you would be hard pressed to guess correctly.

With Rancilio’s new specialty division, the company has pulled together a machine that ticks the boxes most baristas like being ticked. Now, I don’t speak for everyone when it comes to coffee machines, but if I could be so bold as to assume that most coffee professionals want a machine that provides:

  • Quality and the reliability.
  • Ease of use and functionality.
  • Confidence that their equipment will work with you

The RS1 is this and so much more. Yes… That’s right, I’m talking about you, the coffee technician, and also you over there the sales person taking calls at 5:30 in the morning and 7 at night because that’s the supportive person you try to be.

“Josh! Get to the point!” I hear you say. Ok! Fine, let’s get down to business

RS1 Steam

Temperature Profiling: Better coffee or party trick?

The RS1 is an espresso machine with one major difference: temperature profiling

While most high-end espresso machines allow you to set a precise brewing temperature, the RS1 also allows you to change the brew temperature up or down during the shot.

The way it works is a large boiler at the back of the machine feeds water to a smaller boiler tucked inside the group head. If you want the water to cool down during your brew, it mixes cold water into the hot. On the other hand, if you want the water temperature to increase during the brew there is a tiny but powerful heating element to boost the temp.

Why would we want a ‘temperature profile’ anyway?

If you’re anything like me, your first question is “why?”.

Well, if thermodynamics and laws of solubility are to be believed, extraction efficiencies are highly affected by temperature. Typically, but not always, the solubility (that is, the capacity of a material to be dissolved) of a chemical is increased as temperature increases. That said, some solubilities can decrease with increasing temperature… it can be complicated.

And for coffee, a mixture of hundreds of compounds, the impact of changing temperature on the resulting brew will be even more complex. But, thankfully, there is no better way of measuring changes in temperature on taste than by actually tasting the coffee.

And that’s what we did.

Experiment #1: Constant Temperatures

Our first tests focussed on the effect that a constant temperature has on flavour and preference. We did multiple brews on 3 different styles of roast, assessing things like flavour, sweetness & body.

All coffees were brewed using a recipe of 21.5grams in, 40 grams out in 25-28 seconds. Our tasting panel consisted of a highly experienced taster, a moderately experienced taster as well as a less experienced taster. All extractions were brewed twice to check for consistency.

For this first test, we set the RS1 to extract the coffee at constant temperatures of 87 degrees, 91 degrees and 95 degrees.

rs1-chart-constant-temp-static

Light Roast Coffee: As shown, there is not a significant difference between extractions for the light roast coffee, except in regard to ‘smoothness’. This correlates to a drop of quality mouth feel and texture for the 87-degree brew. We also detected a small decrease in acidity for the higher temperature extraction.

Medium Roast Coffee: Alternatively, with the medium roast we see a big increase in acidity, smoothness and sweetness for a higher temp, medium roast.

Dark Roast Coffee: The lower temperature decreased the quality of every aspect we tested for whilst the other two extractions remained very consistent. Maybe the old Italian lever machines were on to something.

Experiment #2: Temperature Profiling

Next up was temperature profiling. Would increasing or decreasing temperature during extraction make a difference?

To find out we set up temperature profiles for each roast profile from 87 to 92 degrees and 92 degrees down to 87. For simplicity’s sake, we averaged the scores of our 3 tasters and here is what we found.

rs1-temp-profile-chart

To simplify the data, I averaged the scores for all three roasts to identify the overall trends.

Across the board we scored the ascending profiles higher, even if only by a small amount.

While our data suggests that there is not a big overall difference in quality between ascending and descending profiles, the most interesting component was the way that the temperature profile affected the acidity and body of the coffee.

With the ascending profile, the acidity was not only of a nicer quality it was also a higher quantity. However, with the descending profile, the coffees all had a more apparent body.

This could lead to roasters having more control over the consistency of their coffee between sites or perhaps being able to increase body for blends while highlighting acidities in single origin espressos.

Rancilio RS1 touchscreen

Other Features we Like

The other big thing that could be a massive selling point for this machine is the user interface.

As a card-carrying millennial, I love a good touch screen (Thank you Star Trek: The Next Generation). Take all your physical buttons and leave them in the 60’s. Touch screens aren’t even the future, we all use them in our daily lives so naturally, it makes perfect sense to have them on a coffee machine.

As a trainer, especially one who has some familiarity with UNIC systems (which featured touch screens), it feels a lot easier to explain features to baristas and cycle through multiple menus quickly during service.



On top of the ease of use, you can also control the options you make available to the barista. Do you want your baristas to stick to a specific menu, you can lock them out of the volumetrics and temperature control while still allowing them to change steam pressure? Or maybe you require your staff to change things on the fly depending on flavour at the time and want to give them full access. Or maybe you don’t want anyone playing with the settings at all. This is great if you are in charge of multiple sites and want to keep consistency between them or you lease machines to varying types of operator who have different needs.

One downside of The RS1 is that portafilters are incredibly heavy. At a time in the industry where manufacturers are designing things around reducing physical strain, this seems like something that could be improved. They do look impossible to break and the thick metal would provide a lot of thermal mass to keep things warm… or cool.

The final thing. The cherry on the cake. QR codes people… QR codes! They’re like bar codes but squarer. If there’s a maintenance issue inside the machine:  flow metre issues, partial blockage, whatever it may be – the screen displays a QR code. The barista can scan the QR code and send it to their technician who can then know exactly what is wrong.

The future is now.

Conclusion

The RS1 crams a lot of functionality into a very tidy machine. From its stylish and sturdy design, to its customisable interface and the ability to adjust temperature with incredible precision – it’s a pretty compelling package.

Of course, a machine like this doesn’t come cheap. In Australia, the Rancilio RS1 has a list price of $17,589 for the 2 group, or $20,889 for the 3-group model.

That puts it in the same price range as the iconic La Marzocco Linea PB, which has undeniable brand creds, but lacks the temperature profiling feature of the RS1. If you’re looking for precise brewing control, the Sanremo Opera 2.0 also includes pressure profiling & enough digital controls to hack the Pentagon – but it costs around $8000 more than the RS1 & requires 40-amp power.

Ultimately, the RS1 would be a good choice for a café focussed on precise temperature control for bringing out the subtleties in a range of different coffees…as long as you’re willing to think a little different.


Click here to find out more about Rancilio Specialty.

If you’re new to the world of commercial espresso machines, check out our guide to get you started.


 

Josh Bowen
Josh is a coffee master, pulling shots, perfecting brews, and troubleshooting like a pro. Motivated by the buzz of the industry Josh traded a lucrative career in psychology to follow his love of all things coffee. As part of the Coffee Science & Education Centre (CSEC), Josh spends his time educating baristas & testing new equipment. Not only that, he still finds the time to use his skills in our Manly Vale espresso bar.