Aillio Bullet V2 separates roasting fact from fiction

Aillio Founders Jacob and Jonas Lillie explain why the use of infrared technology is set to take the guesswork out of roasting
Aillio Bullet V2

Aillio Founders Jacob and Jonas Lillie explain why the use of infrared technology is set to take the guesswork out of roasting.

Scientists have said our best ideas develop in the shower thanks to a relaxed state of mind and release of the brain chemical dopamine. But in the case of Jonas Lillie of roaster manufacturer Aillio, his best idea evolved while brushing his teeth.

Jonas has been trying to find a solution to the moisture build-up and dust collection inside the protective germanium glass of the Bullet roaster he and twin brother Jacob had developed.

“I had been thinking about it for a while but on this one day I had an epiphany. I thought: ‘How can you have an infrared sensor looking at the roasting beans without glass for protection?’ Without it, the sensor would be exposed to smoke and just break down over time – it needs to withstand 145°C,” Jonas says. “Then the idea popped into my head – a very, very tiny fan.”

At just 20 x 20 millimetres in size, the quick spinning fan at 15,000 revolutions per minute blows enough air into the drum of the roaster around the exposed sensor to protect it from gathering dirt or moisture. 

“Some people would say, ‘well you’re just blowing cold air into the drum’. But it’s not an issue. The high-pressure air barrier is just enough to protect the probe,” Jonas says. “It’s also about having the right design and the right angle of air circulate the probe. It’s now a patent design.” 

The Aillio brothers first came onto the coffee scene in 2016 when they launched the Bullet R1, a small-volume roaster that uses induction heating to roast a kilogram of beans in just nine-and-a-half minutes, or less for small volumes.

The 5.9-litre, 2.8-kilogram drum of the Bullet can reach temperatures of up to 310°C, measured using an infrared temperature probe. This device records the amount of light of a specific wavelength (infrared) emitted by an object, and is not influenced by batch side or weight. 

Aillio Bullet V2
The Roast.World online platform monitors the performance of the Bullet V2 throughout its roast.

“This probe was an innovation for version one of the Bullet, but as time has gone on, we also learnt from our customers what we need to improve, like cleaning access to the probe,” Jonas says. “It’s a five-minute job, but people would just forget to do it, and when dust and moisture build up, it really can change roaster output over time.” 

That’s where Jonas’ bathroom epiphany changes the game. The small fan positioned inside the roaster means fewer maintenance issues and more accurate data. The challenge, however, was how to install the new infrared bean temperature sensing system (IBTS) in more than 1500 Bullet roasters already on the market. 

“We didn’t want people to be disrupted by this change so we have made the probe a permanent part of our V2 Bullet roasters, and compatible in V1 models, which can be easily fitted and replaced for just US$60. All you need is a screwdriver,” Jonas says. “If you consider the costs, we’re actually losing money on this replacement, but we think it’s such a good long-term solution for roasting. The dollar value is not important – the fact that it does a better job is.”

More than just a device to help improve the longevity of the roaster, Jacob says the new IBTS is proving to be a game changer and is already challenging current roasting practices.

“When you read books about roasting, they say you should never stall your roast, which means that the temperature always keeps going up,” Jacob says. “But what if it was actually dropping? What if everything we thought we knew wasn’t right? 

Jacob says shapely curved roasts have become synonymous with a good roast, but the curves represent a plot of the bean probe’s temperature, not the actual bean temperature. 

“The data is leading to false pretences because it’s generated from a lagging temperature probe, making it impossible to compare bean probe data across different batch sizes,” he says.

“It is well-known that the thermometric lag of traditional bean probes creates data that is inconsistent and of limited use. These limitations have held back data-driven roasting for many years.

Aillio Bullet V2
The Bullet R1V2 new induction board.

“People have long-been talking about the classic probe, trying to improve it by making it thinner and a little longer, and talking about the turning point (when the traditional bean probe temperature begins to rise following the charge) not being the turning point.”

Jonas eludes to the fact that “real time” profiling is not in fact real at all, and that the misleading probe data suggests we have only been guessing what really occurs during a roast. 

“Why has no-one changed the way we roast for the past 25 years? Because most people don’t realise the way they roast is wrong,” Jonas says. “Anyone in their right mind who wants more accurate data will see the infrared probe as a breakthrough.”

To test this, Jacob and Jonas compared a roast using a traditional probe versus the infrared bean sensor. It turned out that the information was lagging by minutes.

Unlike traditional probes, the IBTS does not experience thermometric lag because it directly senses the surface temperature of the beans. In the Bullet V1, the infrared probe was looking upwards into the drum, recording only the drum temperature. Now in Bullet V2, the infrared probe has a 12-degree cone-shape field of view which now points downwards into the roasting chamber and bean mass.

“As far as we know, ours is the very first system in the world to allow users to profile their roasts using infrared data – the most accurate, real-time reading of bean temperature without lag. We firmly believe that better data makes better coffee,” Jacob says. “With further use, maybe we’ll find out that we can stall the roast. Maybe we even have to go down in temperature after you reach a peak. We don’t know that yet, but finding out will be exciting.”

The hope with the implementation of IBTS across all Bullets will be a much easier, more predictable, and more reliable method of roasting.

The Bullet V2 is distributed via Espresso Company Australia.

Read about more products available through Espresso Company Australia:
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Jimmy scales
Le Nez Du Café

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