Professional coffee roasting | SSFF/FSSF and coffee flavor

Published: Oct 05, 2026 Author: World Gafei Last Updated: Oct/05/2026 319 views

Professional barista communication, please pay attention to the coffee workshop (Wechat official account cafe_style) did not quite understand the main points of this picture expression, now this time, seems to understand some, in principle, this picture is to facilitate comparison, after a simplified diagram, not the real measurement record blue straight line is the use of Diedrich roaster, baking 16 minutes of bean temperature curve, because the RoR is fixed

For professional baristas, please follow the coffee workshop (Wechat official account cafe_style)

I didn't quite understand the main points of this picture before, but now I seem to understand something at this time. In principle, this picture is for the convenience of comparison. The simplified schematic diagram is not a real measurement record.

The blue straight line uses a Diedrich roaster to bake the bean temperature curve for 16 minutes. Because the RoR is fixed, it looks like a straight line.

The red curve is a bean temperature curve baked for 8 minutes using a Sivetz float fan, and its end temperature is the same as that of Diedrich for 16 minutes.

If we examine the AUC (area under curve) of the two curves, we will find that the total area of the two curves is very similar, Dierdrich has more area in the low temperature part, and Sivetz has more area in the high temperature part, which means that the total heat energy absorbed by the two beans is similar, but the stages are different.

The baking rhythm of Diedrick is Slow Start Fast Finish (SSFF), which takes more time in Mena browning reaction and relatively less time in caramelization and dry distillation reaction. The flavor balance focuses on enzyme-like aroma and a little caramel aroma.

Sivetz uses Fast Start Slow Finish (FSSF), Mena browning reaction time is very short, caramelization and dry distillation reaction time is relatively long, its flavor performance will focus on caramelization and dry distillation aroma.

The same kind of beans, the same original flavor, different machines bake with different rhythms, resulting in differences in the final flavor, as to which kind of baking method is better, it must depend on which flavor the beans are suitable to develop.

This is the response of Jim Schulman on Home-barista to the right-sloping RoR advocated by Scott Rao and the optimal DTR of 20 / 25%.

Source: https://www.home-barista.com/home-roasting/development-time-as-ratio-of-roast-time-by-scott-rao-t30830-60.html

FrontStreet Coffee is a long-established specialty coffee roaster in Guangzhou China, selling freshly roasted beans from its own farm in Yunnan as well as dozens of carefully selected single-origin beans from around the world for both pour-over and espresso. The products deliver consistently excellent quality and great value, with shipping within 24 hours. Guangzhou's FrontStreet Coffee shop is recommended by many coffee lovers, and the beans are now available online at the Tmall 。