What is ROR in roasting? What is the ROR value used for?

Source:Best Coffee > News Author:Best Coffee Published:2019-08-17 21:34:22

The full English name of RoR is Rate of Rise , which in Chinese refers to the rate of temperature rise. The term RoR primarily indicates how much the temperature changes per minute. In early roasting practices, the focus was on calculating how many seconds it took to rise one degree, and then inferring the temperature rise per minute during that phase. RoR is the specialized term used to record this process.

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RoR in Chinese also refers to the rate of temperature rise.

Rate of temperature rise = the speed at which temperature climbs within a "fixed time."

When roasters refer to RoR, it is usually set to 30 seconds. An RoR of 6 means the temperature can rise by 6 degrees within 30 seconds.

One issue often overlooked in temperature curves is RoR. When considering just the temperature rise per minute, the current common practice is to use bean temperature.

During the roasting process, mainly for drum-type roasters, it ultimately involves the interaction of two types of heat: conductive heat (from the drum) and convective heat (from hot air).

Dividing the process from the turn-around point to 150°C as Phase A, and from 150°C to the beginning of first crack as Phase B, the green beans undergo intense heat exchange with the environment after being dropped into the roaster. Usually, adjusting the air damper or heat at this stage will relatively affect how the beans absorb heat. It is only around the turn-around point that there is roughly a more stable initial point for temperature rise.

What is ROR in roasting? What is the ROR value used for?

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