Beate Øvland 8/7/22 Beate Øvland 8/7/22

Adjustable roasting parameters

There are many parameters you can adjust before or during roasting. You will find some of them on the main touchscreen, the rest are located in ROAST SETTINGS.

Sections:

Main screen parameters

These are the adjustable parameters located on the main screen of your roaster.

1. DEVELOPMENT TIME. You can change the development time during the roasting process without switching to manual mode. Tap on DEVELOPMENT TIME and adjust the time using the rotary knob. Once “First Crack” is registered, the timer will start and cannot be changed. By tapping the countdown, you can cancel the auto drop and drop the beans when you want to.

2. AIR TEMPERATURE (ET).

This is the primary variable for adjusting a roast. The sensor sits in the upper mid-section of the drum. This temperature responds very rapidly to changes in heat input. If adjusting the ET, you will switch to manual mode (Manual ET Profile).

3. BEAN TEMPERATURE (BT) AND DRUM TEMPERATURE

Instant temperature measurement of the bean surface. Adjusting BT on the screen will not switch to manual mode. Instant measurements of the drum temperature are also visible below the BT temperature.

4. FAN.

The fan setting changes the speed of the exhaust fan. Note: If you have a fixed ventilation hose out of the room and smell roasted coffee, this can be because the exhaust fan setting is too low.

IMPORTANT: The higher the airflow, the more energy is used in temperature-based profiles. More increased airflow will have an impact on the roasting time. However, the effect is not as significant as you might have experienced with traditional open drum roasters. We suggest adjusting the temperature or power to adjust the total roasting time. We have roasted great coffee on both low and high airflow. It depends on the profile overall – and of course – the coffee.

5. POWER.

When controlling the power, any changes made to the power percentage on the screen is directly changing the power input to the heating elements. You will switch to manual mode if manually adjusting the power (Manual Power Profile).

Roast settings parameters

These are the adjustable parameters located in your roaster via ROAST SETTINGS.

1. REDUCE PWR AFTER FC.

If you roast using a Power profile, this setting can automatically reduce the power after a First Crack event has been registered.

For example: if the power setting in the profile is 80%, then a 10% reduction would mean that the power is reduced to 72% (10% of 80% power is eight percentage points).

Watch this video to learn more about this useful feature.

2. WAITING TEMPERATURE (charge temperature).

The starting air temperature for Power Profiles. You can set a preheat temperature when creating a profile as well, but if you wish to vary between batches, for example, you can leave that field blank and just adjust from the screen in between batches instead.

IMPORTANT: The waiting or charge temperature is set in the profile creator for temperature profiles. Depending on the profile, it can be beneficial to have a higher or lower starting temperature than the profile itself. A high charge temperature will increase the conductive heat transfer at the beginning of the roast, as the roasting chamber will store more heat. A lower charge temperature will help reduce energy consumption if the machine is idling for more extended periods between roasts and will also shift the heat transfer more towards convection in the beginning.

3. DEVELOPMENT (AUTO DROP) SETTING.

Choose between percentage (%) and seconds (SEC) for development time after First Crack. If percentage is used, the development time will be calculated from the total time.

4. MAIN MOTOR SPEED.

Manual adjustment of the drum speed. It can be adjusted at all times during a roast without switching to manual mode.

IMPORTANT: Changing the Main Motor Speed (RPM) of the paddles agitating the coffee will have a much more significant impact on the roast than changes made to the airflow. Initially, higher RPM equals a faster roast. With higher RPM, the coffee is “thrown” into the hot air and spread more evenly in the chamber. With higher RPM, the coffee will be exposed to the hot air more efficiently. Still, it will also impact the precision of the bean temperature sensor since the sensor will pick up hot air and bean surface temperatures.

5. BUZZER TEMPERATURE.

The buzzer will make a sound when a set bean temperature is reached. This is helpful if you do not want to miss, e.g., the First Crack event.

Watch the video below to see how to set up the Buzzer on your roaster.

6. YELLOWING BT THRESHOLD.

The bean temperature which must be reached for ROEST to mark a Yellowing event. Note: It is set at 175 degrees Celsius by default which is valid for a 100g profile. If you roast a different batch size, you should adjust it.

7. FIRST CRACK DETECTION.

If you have purchased a ROEST sample roaster with the FC detection system, tap ON to activate this feature. Here you can adjust the following parameters:

7.a. BT Threshold: Bean temperature that has to be reached in order for First Crack detection to start registering single cracks.

7.b.Trigger count: You can choose how many cracks are needed in order to register the First Crack event automatically. We recommend 3-5 cracks.