The Newton Brua is a striking espresso maker hailing from New Zealand.
As a long-term manual espresso geek, I’m always curious to try new and exciting gadgets.
So obviously, I was thrilled when the company reached out to borrow me a review unit of their new and improved S2 version (This version has a pressure gauge, which was absent in the previous iteration).
At first glance, the Brua ticks a lot of boxes.
It boasts a striking yet minimalist design. And the founders have taken inspiration from one of the OG’s of physics, Isaac Newton himself!
But does it also deliver where it matters – in the cup?
I set out to find out, putting the Newton Brua through rigorous testing to determine its strengths and weaknesses.
⚠️ Heads up!
When this article was first published, I included a YouTube video to add some extra depth. I have since chosen to remove this video review.
There are a couple of reasons for this, but the main one is that upon corresponding with the owners, I realized that the video could profoundly affect their business and livelihood. Since this is a tiny, bootstrapped start-up, this was something I felt uneasy about.
While I still stand by the opinions in the video, I wish certain parts came off differently.
There’s especially one segment of the video that I would like to change: I was sitting down when I was demonstrating how to pull a shot, which made the whole brewing experience look uncomfortable.
Fundamentally it is not an awkward device to use.
(The reason for sitting down is technical – I wanted to stay in the camera frame. Nothing special here; I did the same when I reviewed the Flair and Robot.)
However, it’s challenging to edit a video after publication. While YouTube does offer the option to cut specific segments, that would leave an empty gap and probably make it even more confusing for new viewers.
So to avoid this situation, I have decided to take the video down.
As I mentioned, I still stand by my initial opinion expressed in the video, but my fundamental issue with the device is not ergonomics; it’s thermal stability.
For that reason, I have expanded this blog post about the device to focus mainly on preheating and temperature management.
About the brand
The Newton Espresso brand started in 2017 in a similar fashion to many other modern coffee ventures; as a Kickstarter crowdfunding project.
The device is invented by designer duo Hayden Maunsell and Alan Neilson.
Initially, Hayden aimed to find a solution for his own coffee needs that was cost-effective and environmentally friendly. He envisioned a simple espresso press that could make traditional espresso using hand power instead of electricity.
Hayden took his sketches to Alan Neilson, a craftsman with expertise in mechanical product design, and the two began turning their ideas into reality. The design evolved over time and eventually became the current Newton Brua 2P espresso maker.
The founders still handcraft each unit in Hawke’s Bay, New Zealand, to this day. For that reason, there can be some waiting time if you want to purchase a unit.
The Newton Brua is a straightforward device if you’re familiar with manual espresso makers.
There’s a big brew chamber where you add the water.
Then, you screw in a 51 mm basket underneath the brew chamber. The choice of a 51 mm basket is sensible. It’s a pretty standard size, making it relatively straightforward to purchase 3rd part accessories such as funnels, baskets, and levelers from various vendors.
It also requires less pressure than a 58 mm basket, making the lever more comfortable to push down.
The overall design is quite minimalist and straightforward, especially compared to typical manual espresso makers, which have many loose parts to keep track of.
This device is more of a self-contained unit where you have the basket and its holder to keep track of.
In theory, this makes the Brua a more attractive option as a daily driver to have on your kitchen counter.
The Newton Brua also comes with a quality tamper that uses the same brushed orange aluminum as the brew head. A lovely thing.
However, my admiration quickly transformed into irritation.
The surface area of the tamper had been taped. When using the tamper for the first time, a bunch of grounds got stuck on the tamper. This resulted in a destroyed puck and a tamper needing cleaning under running water.
Apparently, some gluey residue was left after removing the tape.
When it comes to the overall impression of the construction of the device, it’s mixed.
The brew head is beautiful and solid. It is crafted out of smooth aluminum. On my unit, it’s orange, and even though it’s not my favorite color to sport on my brew bar, it’s undeniably well made.
The brew head and tamper feel luxurious and nicely crafted, whereas the stand feels a bit wobbly, especially the connection between the lever and the brew head.
As for clearance underneath the brew head, you will be able to fit most espresso and cappuccino cups, but probably not glasses.
You only have a few options in terms of scales since the space between the legs is relatively narrow. It seems ideal to redesign this in future releases, so an Acaia Lunar or Timemore Black Mirror Nano could be accomodated.
However, the popular Weightman scale does fit, which many budget espresso enthusiasts will appreciate.
The brewing in itself is pretty straightforward.
You add finely ground coffee to the basket, put it inside the basket holder, and screw it onto the body.
Then, add water to the brew chamber and lift the lever. A nifty gasket will let water flow down from the brew cylinder and into the headspace just created.
To “pull” the shot, simply press the lever down. This is a direct lever, so you can rapidly change the pressure if you wish to do so.
If your grind size is not too fine, pulling the shot while standing should be relatively comfortable if you apply a bit of body weight.
However, the overall design can feel limiting if you’re grinding very fine. The lever is slim and on the shorter side, and the legs are narrow, so wrestling the device can feel a bit janky compared to more sturdy designs such as the Cafelat Robot or Flair 58.
A lukewarm Preheating experience
The major hurdle with almost all manual espresso makers is to ensure a high enough brewing temperature. This requires preheating.
Newton has chosen an approach where you have a colossal brew head. The idea is that it will be very stable once you get it up to temperature.
This is how the company describes it on its website:
“The solid, food-grade aluminum cylinder rapidly absorbs heat from the water during preheat (making preheating quick), and it stays hot for a looooooooong time.“
The above is actually correct when you look at it sentence for sentence. The brew head rapidly absorbs heat from the water, but that also means that your brew water will be at a lower temperature than ideal. Let’s say you put 99 °C water in. If you only brew at 75 °C degrees, then you’re missing out from an extraction point of view.
It’s also true that the brew head stays “warm” for a long time. But warmth is not an objective quality.
If you talk about the weather at a holiday destination 35 °C would be considered warm. But in the context of espresso brewing temperatures, the industry standard is usually between 88-96 °C.
In my testing period, the brew head of the Brua has only briefly been close to these temperatures.
The company acknowledges that preheating is an important step. On their website demonstration, the brewer is preheated once, but in a direct message, the founder suggested two preheats.
However, following this protocol, the shots still tasted slightly sour or acidic during my testing period. This was with rather dark beans, a standard espresso roast that should be easy to get good results with. Not some modern Nordic omni-roast.
Having tested many manual espresso makers over the years, I have become quite attuned to the taste of a slightly too-cold brewing device.
I got curious about the brewing temperature and hooked up two external thermocouples connected to Artisan to find out the temperature I was brewing at.
For some additional perspective, I compared the Newton Brua to the Leverpresso Pro, another manual espresso maker in my collection.
The Newton Brua didn’t reach sufficient brewing temperatures with two or three preheat cycles during these tests. Or, to put it differently, the boiling water rapidly decreases in temperature to something below recommended espresso brewing temperatures (88 °C and up).
When you look at the temperature fluctuations on a graph, you quickly notice that the peaks are much sharper with the Newton Brua, indicating that the brew chamber is stealing the temperature from the water rapidly.
The Newton Brua’s brew chamber can only fit 80 ml of water, while the Leverpresso has 140 ml of water with a closed design and rubber-insulated steel.
The contrasting designs account for some of the difference in heat retention, while each brew head’s water volume and total mass make the most significant difference.
The Newton brew head is significantly heavier. At the same time, it’s supposed to be heated with almost half the energy of the Leverpresso. This is a difficult task.
Mind you; the Leverpresso was the most fitting comparison in my collection since it also has a passively heated steel brew head.
But to investigate this even further, I ran the same experiment to see how the Brua would fare against the Picopresso, the Robot, and Flair 58.
For various reasons, these are less ideal comparison partners:
- The Flair 58 has a built-in heating element giving it an unfair advantage.
- The Robot has a separate basket-brewhead with minimal contact with the steel portafilter. Also, the water is not in contact with the piston before you press down the two lever arms. Furthermore, I had to plug the basket with an AeroPress silicone seal to ensure that the water would stay in the basket for the duration of the experiment.
- The Picopresso is small and made of plastic
With all these devices I followed a protocol similar to my testing with the Leverpresso, and the results were very similar. In all cases, the Newton Brua would end up brewing at a lower temperature than the other test subject. You can see that data here:
Versus Flair 58 👇
Versus Cafelat Robot 👇
Versus Picopresso 👇
Each time, I made sure to check and calibrate the thermocouples at different temperatures to see that there were no issues. I also used a third external digital thermocouple to double-check the readings as I was running the experiments.
Finally, I gave the Newton Brua the advantage of getting the water just off boil, whereas the other brewers would get filled subsequently.
I find the temperature test to clearly indicate that the Brua’s design is suboptimal in some critical ways.
However, there were a few other findings in my test period that I also want to address.
- The chamber is relatively small, at around 80 ml. This means that pulling long shots can be challenging. You’ll have to underdose the basket to brew at 1:3 ratio or wiggle the lever while filling the chamber to ensure no headspace.
- Another area for improvement with my particular unit has been the accuracy of the pressure gauge, which I have to put into question.
During testing, the gauge usually showed 4-5 bars, even though I used a lot of force and put most of my body weight on the lever.
According to the company, around 20 kg of pressure on the lever should give you 9 bars, and I was sure I was applying more force than that.
To double-check, I put a digital scale underneath the unit, but the result was the same: 4-5 bars only.
This might be an issue with my test unit, but I haven’t experienced the same with other pressure gauge-equipped manual espresso makers I have tested. (Flair 58, Flair Pro, Cafelat Robot, Leverpresso Pro etc).
The Newton Brua is an interesting device. It has a striking design and appears to be a solid daily driver with a simple workflow and only a few moving parts.
But it also has some considerable flaws.
The imprecise pressure gauge on my device is not my biggest complaint. I’m sure that’s easy to fix. It could be an issue affecting my review unit only.
The massive brew head and the required preheating are a more significant concern. Getting it to a sufficient espresso brewing temperature will require a tremendous amount of preheating.
Whether you like the design and workflow is a subjective thing. I’m not going to make any judgements here.
However, what’s objective is that the Brua is simply brewing at lower temperatures than other popular manual espresso makers.
The Flair Pro 2 is another device with a massive brew head, but at least with that device, you’ll be able to boil the brew head in a pot for minutes to ensure proper heating. Unfortunately, due to the Brua’s design, this is impossible.
I paid little attention to physics in high school, so I don’t know Isaac Newton’s law of heat transfer in detail. But I’m sure he would also say that preheating the Brua’s brew head is an uphill battle.
I still think the Newton Brua is a gadget with a lot of potential: A redesign of the brew head, with less mass and more space for water, would likely make thermal management much more straightforward. I would be curious to test a version like that.
However, if you believe that the industry-accepted wisdom of a brewing temperature around 88-96 °C has some merit, it’s hard to recommend the S2-version currently available.