Rubasse Technology

We are constantly investigating the best solutions that makes your roasting more comfortable, scientific, efficient and productive. We achieved these in various ways - developing unique heating source, integrating automatic systems, improving performance and providing a better, smarter and more sustainable solutions for you.
Fully-Automatic Shop Roasters

Fully automatic roasting system covers the whole roasting process for you, increasing efficiency and productivity.

Rapid pre-roast warm up and smart warm up temperature idle

preheat

 

With one simple touch on the button, all Rubasse roasters can perform warm up protocols and reach your desired temperature within 5 minutes. (manually warming up traditional drum roasters might take you more than 30 minutes)

Also, before roasting and between different roast batches, our roasters can idle at your selected temperature with precision for any designated duration.

 

Together, the smart warm up function and our automated roasting system enables hyper-efficient roasting on all Rubasse roasters.


Automated Functions Throughout Roasting

fullyautoroasters

From roaster warm up to post-cooling unloading, our automated roaster functions have you covered:

 

Step1:Auto-charging after completing warm upautocharge

Step2:Fully automated smart roasting, following your selected roast profile by automatically adjusting heat application, airflow, and drum rotation speed.
 

autoroast_coffee roasting machine

 

Step3:Auto-discharging after reaching desired end point on the selected roast profile

autodischarge

Step4:At the same time, the roaster will start its auto-cooling procedure. The cooling duration can be set to your liking.
auto_cooling

Step5:Auto-unloading the roasted coffee after cooling is completed.

auto_unload

 




 
Actual roasting workflow demo

 

Autopilot Profile Replication

Our roaster replicates your selected bean temperature curve and the roast chamber’s underpressure profile, guaranteeing repeatability and consistency batch after batch.

Rubasse PID Backtracking profile replication algorithm

 

When simply following and reproducing power and airflow settings from previous roasts, the temperature curves might look nothing like the desired profile.

 

heatpower_compensation

 

But our profile replication algorithm does more than just reproducing your previous heat application settings – it can actually compensate for the temperature deviations and adjust the heating settings responsively.

smart_replication_your_roast

 

Besides roasting temperature compensation, our profile replication algorithm also tracks and follows the roasting systems underpressure profile of your previous roasts, enabling more accurate roast replications.

airflow_compensation

 

Unique Near-Infrared Central Heating

Coffee beans can absorb the heating energy more efficiently via radiation heat transfer, enabling our roaster to create clean and vibrant flavors easily.

Why use infrared radiation?

patendted_centered_near_infrared

Near infrared radiation(NIR) has the ability to penetrate up to 1cm under the surface of grain products

 

near_infrared_halogen

By choosing NIR as the primary method of heating, our roasters can easily roast the coffees more evenly, creating a cup profile that is clean, transparent, and vibrant, fully showcasing the flavor potential and terroir of each and every coffee.

 

Rubasse's Heating Halogen lamp:

非傳統電熱烘豆機的燈管

 

 

One of the most important aspects when designing a NIR-based heating element is the selection of NIR wavelength. Rubasse roasters all have an NIR heating lamp that emits radiation energy having wavelengths between 750 nm to 1500 nm. Infrared energy lying in this area had been proven to be better absorbed by grain products (Zhongli, 2010).

hear_radiation_evenly_heat

 

Rapid heat response:

Unlike typical electrical coffee roasters, our NIR heating technology enables powerful and ultra-responsive roasting comparable (if not better) than gas-powered roasters. Center placement NIR heating really is like harnessing the best of both worlds: the power and the responsiveness of gas burners combined with the precise linear heat adjusting abilities of electric heating elements.

 


Power adjustments: Linear, precise control simply achieved by altering the input wattage.Rapid heating: ultra-responsive power adjustments, corresponding temperature and rate of rise changes can be observed within 3 seconds (fastest scenario).

 

Touchscreen control and profile saving

All functions of our roaster can be operated with a simple touch on the touchscreen interface

 

 

record_all_roasting_parameter

During roasting, all models of Rubasse roasters can record the curves of the different sensors, and real-time plotting of the curves will be shown on the touchscreen panel used to control the different roaster settings.

 

Together with our responsive heating technology, this integrated design enables straightforward and intuitive control during every single batch of your roasts.

touchscreen

Settings you can alter:

power, airflow fan speed, drum rotation rpm


Data recorded:

Power settings, Airflow fan Speed settings, Drum rpm settings, Bean temperature readings, Exhaust air temperature readings, Drum temperature readings, Rate of Rise, Calculated amount of released moisture, Differential Pressure readings(underpressure of roasting system), Turning point, time and temp. of first crack, time and temp. of second crack, end temperature and roasting duration.

 

 

Exchangable data:

The data profile recorded can be exported or imported via USB connection. Roast profile data can be shared between all Rubasse roasters of the same model.

 

 

Artisan compatible

Our roast profiles are recorded in CSV format files, and can be opened(but not recorded) using Artisan (version 2.6.0 or above).

 

Actual layout of the touchscreen panel during roasting:

rubasse_ui

Linearly controllable airflow

Adjustable fan speed enables linear and precise control over the roaster’s airflow.

 

Unique airflow design for maximum heating efficiency:

 

As shown below, our roaster’s airflow is designed in a way that the cold air would first be forced through our NIR heating element before entering the roasting chamber, where the heated air would be used to help distribute the roasting energy more evenly throughout the roasting coffee.

airflow_system

Linear airflow control using variable frequency drive fan motors:

As many roasters have experienced, airflow stability can have a profound impact on the final flavor of roasted coffee. Our linearly adjustable airflow ranges from 25% to 140%, and by altering the fan motors rotation speed, one can make airflow adjustments with precision up to 1%, giving a total of 116 different airflow settings within the whole range. This kind of adjustability enables our users to have total control over airflow during every batch of roasting.

 

exhaust_airflow_test

Linear relation between airflow setting percentage and actual volume flow rate of exhaust air as demonstrated above.

 

Chaff collection:

A well-functioning chaff collection system is a crucial factor contributing to a roaster’s ability to do back-to-back batch roasting. No matter the designated batch size, all Rubasse roasters are equipped with cyclone chaff collecting systems, efficiently separating chaff and dust from the roaster’s exhaust air. Together with our designed quick release chaff collection bin, cleaning and maintenance during and after roasting is a breeze for our users.

 

chaff_collector

Double-Wall Stainless Drum

All our roasters have a stainless double-wall roasting drum which leads to superb heat insulation and highly efficient heating.

Double-Wall Stainless Drum

double_wall_stainless_drum

304 stainless steel Double-wall design, having insulation properties similar to a thermos bottle.

Combined with the center placement of our heating element, this design largely improved the efficiency of energy usage on all our roasters.

 

 

Unique roasting drum - resonant cavity-like design

near_infrared

 

The heat energy emitted from the center-placed NIR heat element will:
a. heat up the coffee beans directly,

b. first be reflected from the drum’s inner surface then heat up the coffee beans,
c. heat up the roasting drum,and
d. heat up the air within the drum.

And due to the combination of our heat source and drum design which creates a roasting environment that resembles a resonant cavity,

the heat “trapped” within the roasting drum will eventually trend toward the coffee beans that has the lowest temperature within the drum.

 

A fully loaded 3kg Rubasse micro roaster reaching a peak ROR of 36°C/min.

responsive_ror

 

 

 

Superb heat retention ability:

Utilizing the fact that NIR radiation do not penetrate stainless steel easily, together with the double wall design,

the majority of the energy emitted from the heating element is “locked” within the roasting drum.

Besides the obvious benefit being increased heating efficiency,

another advantage is the improved comfort regarding the roasting environment – Long gone are the hot and sweaty production days!!

friendly_roasting_environment

The outer surface of the roaster’s roasting chamber remains at 40°C while roasting with a bean temperature reading of 200°C.

Notice that the room temperature easily stays below 26°C.

double_wall_drum

The double wall stainless steel drum design, resembling that of a thermos bottle.

 


Bidirectional drum rotation:

Here at Rubasse we thrive to utilize all energy as efficiently and stably as possible,

hence the unique design of the bidirectional drum – when roasting, the drum rotates in a counterclockwise direction,

pushing the coffee backwards towards the spot where the just-heated airflow enters the drum, increasing convective heating efficiency;

when discharging, the drum rotates in a clockwise direction, pushing the coffee forwards into the cooling tray.


bidirectional_drum_rotation

Precise digital sensors

Our roaster comes with a high precision sensing system which monitors real-time bean temperature, exhaust temperature, drum temperature, roasting chamber’s underpressure, and exhaust air humidity.

digital_roasting_system

What we measure in our roaster: bean temperature, exhaust air moisture content, roast chamber differential pressure, drum temperature, and exhaust air temperature.

 

 

Bean Temperature Probe:

measuring the temperature within the bean pile.

drum_roasting

Our K type thermocouple is made from carefully selected wires and is tailored to our needs. Within the typical coffee roasting temperature range, it can reach an accuracy of +-0.1°C.

Also, the shape design of the temperature probe and the possibility to make fast, accurate heat and airflow adjustments allows users to roast as low as 200g even on the 3kg machine, giving you much more flexibility regarding roasting batch sizes on our roasters.

 

 

Exhaust Air Moisture content:

reflecting the amount of moisture being released from the coffee while roasting.

crash_and_flick


One of our exclusive functions is the ability to record “real-time released moisture content” data in our roast profiles. This function is based on sensors that detect real-time exhaust air moisture content, and this data can be used to calculate the real-time released moisture content value which our roaster displays and records in the roast profiles. With this data, our users can gain more insight into what changes are actually occurring when coffee is being roasted.

 

 

Differential Pressure Meter:

a more precise measurement for actual exhaust airflow


The pressure difference between the roasting drum and the surrounding environment can reflect the actual amount of airflow during the roasting process. As many might already know, the amount of airflow during roasting is one of the crucial factors that affects the final cup profile. By measuring and showing the differential pressure, users can utilize this information in combination with the fully linear airflow control to perform much more precise and informed airflow adjustments on our roasters, giving you unprecedented controllability and ease of use.

 

Drum Temperature Sensor:

measuring the temperature of the drum’s inner surface

drum_temp
Roasters probably are familiar with some roasting defects related to an overheated drum (e.g. scorching or excessive oiling on the bean surface). When roasting, it is crucial to make sure that the temperature of the roasting drum is within a “safe” range so it won’t sabotage the final flavors within the cup. In our roasters, we have a customized infrared temperature sensor that monitors the real-time temperature of the drum’s inner metal surface, enabling roasters to know more about the actual roasting environment and have better control overall.

 

 

Exhaust Temperature Sensor:

measuring the temperature of air leaving the roasting chamber. 

exhaust_temp

 

Exhaust air temperature is a temperature measurement that is closely related to the air temperature within the roasting chamber, hence it is also highly related to convective heat transfer during roasting. Adding the exhaust air temperature reading to our roasting data and monitoring it in real-time can be tremendously helpful when adjusting and balancing airflow and heat settings when roasting.

 

 

 

Responsive Heating

NIR heating element not only packs a lot of heating power but also responds to heat adjustments quickly, giving you the most control over your roasts.

Direct heating of the coffee beans via radiation emitted from the NIR heating element.

By placing the NIR heating element right at the center of the roasting drum, we greatly increased the efficiency of energy usage and responsiveness of heating during roasting.

 

 

Also, unlike some other electric heating methods, NIR heating technology is responsive by nature. Heat energy emitted from the NIR bulbs can reflect changes in input power almost immediately, so unlike the common impression of needing to account for the “lag” when changing heat settings, controlling our roasters relies much less on predictions and guesses.

heating_power

 

Increasing heat to 30%: rate of rise reacted within 3 seconds. Note that here we are roasting a full 3kg batch on our 3kg Micro roaster which has a 220V, 6000W NIR heating element.







Increasing heat to 100%: Again, rapid changes occured for the rate of rise within 3 seconds.



 

 

 

Cutting off heat: rate of rise drops almost immediately.

 



Cranking up the heat to 100% again: rapid increase in rate of rise observed.

The responsiveness in our roaster’s heating technology not only gives our users more freedom and control over heat application, but also it is actually a key cornerstone to our Autopilot profile replication system.


Safety Measures

Our Roasters all come with Overheating Prevention and Alarm Systems

Our Electric Roasters: None of the potential gas fuel related dangers.

 

Preset limit for warm-up and charging temperature setting.

The preheat limit being set at 260°C acts like an additional safety measure, preventing operations that might result in an overall system temperature that exceeds the safety limit.

 

 

When the Bean Temp. readings exceed 260°C, the system automatically cuts off the heat supply

 

While roasting, if the bean temperature reading reaches 260°C or higher, the coffee beans might already start to carbonize. During such occasions, our roasters are programmed to automatically shut off the heat supply.

 

 

 

When the system Detects Abnormally High Temperature Readings, the Overheating alarm will be set off, and the control over all functions will be taken over by the system’s safety protocol. 

 

Ultra-high bean temperature (factory set at 300°C): During such occasions, control of heat supply, airflow fan speed, and drum rpm will all be taken over by the roaster’s smart control system for fire-prevention, and also the roaster’s alarm will be set off.

 

Sustainability

Roasting at full capacity on the 3kg roaster, each batch only requires 1.1kWh, and all of this energy can come from sustainable sources since our roasters are 100% electric.

Roasting one 3kg batch on the Rubasse micro 3kg roaster only uses 1.1 kWh of electricity.

On the other hand, though actual numbers may vary from roaster to roaster, the average gas consumption of roasting a 3kg batch on liquefied petroleum gas-powered roasters is around 0.25kg. Under Taiwan’s energy prices (July 2022), the estimated cost for roasting one 3kg batch on Rubasse roasters and LPG-powered roasters are 1.8ntd and 10ntd respectively. These numbers indicated that the cost for energy when roasting on our roasters is only 18% of what the typical cost may be when roasting on more traditional machines.


Low carbon emission

By estimation, when roasting the 3kg batches on Rubasse roasters, the carbon emission is around 0.55kg per batch; on the other hand, traditional gas-powered roasters may emit around 0.78kg per batch. The cut down in carbon emission after switching to Rubasse roasters is around 30%.

 

Drastically cutting down waste heat during roasting

The total heat energy generated while roasting a full batch on our 3kg roaster is around 946Kcal, and by calculations based on LPG usage, the heat energy generated during roasting on a more traditional 3kg gas-powered roaster is around 3000Kcal (assuming complete combustion of the fuel gas). These numbers indicated that Rubasse roasters are much more efficient with the task of roasting and bringing 3kg of coffee beans to the desired temperature. This also means that our roasters likely emit much less waste heat (namely 2054Kcal less per 3kg batch according to the numbers here) into the surrounding environment during the roasting process, which means less air conditioning needed and a more comfortable roasting environment.

 

Actual comparison between Rubasse roasters and gas-powered roasters

(roasting 3kg batches).Actual comparison between Rubasse Electric roasters and gas-powered roasters