Soaking

I have been reading about soaking. Does anyone soak in here?
I sometime put the power down to P0 or P1 with a lower drum speed of 5 to allow the bean to soak up some heat before ramping up the power and increasing drum speed a little. I usually soak until the cross over point in the graph.
What experience do you guys have with soaking?

Matt

1 Like

I’ve been experimenting with soaking too. I’ve done 3 roasts “soaking”. One I soaked for 1:30 with zero power. One I soaked for 2 minutes at zero power and another I soaked the beans for 1:45 at power of 2. The beans were all the same, Costa Rican. I did not adjust drum speed on any of them, I kept setting 8 for all. All roasts went well. ROR was well controlled until 1st crack. I had to drag out the roast a tad longer than I like, but the coffee tasted excellent. I’ll definitely keep experimenting.

3 Likes

I typically charge at P6 and just wait a min before increasing to P7-8, not really a soak.
The annotated image below is the same bean, charge temp, and batch size that shows the effect of a soak on my profile.
The dimmed overlay is ‘no soak’ and the brighter forward one is a P2 1:30 soak.


The soaked bean was pretty average, not extremely happy with it. But I haven’t nailed this roast yet.
The non-soaked bean was really strange, Highly astringent and acrid in it’s first sips, but after letting it cool for another 10 mins it cupped with good sweetness and body.

(Both crashed hard and likely diminished the full potential, this Kenyan bean seems to love to crash and stall. I’m having a hard time controlling it post FC but that’s aside from your question)

I have been using the soak for several months and love it. Getting lots of great feedback and can even use it with various roast levels/styles.

@quartzglen introduced a discussion about heat-soak in Sep 2019: Drum Speed in relation to batch weight?

Works well for my purposes… but then I like a dark roast and this seems to support stretching the end of the roast in a way that delivers what I like in some beans.

Bruce

1 Like

I soak for one minute at P0 and briefly pop to P9 for almost every roast now. The results have been excellent and I am reluctant to return to no soak. I developed a recipe that is also used for most roasts and only begin making adjustments near or at the end to get the final result that I set up in advance. I use this process for everything from C to FC+ and have almost 300 roasts on my V 1.5 machine. This might not work for everyone but, considering environmental conditions, local electrical power stability and consistent bean quality, the process has most certainly provided outstanding results for my needs and for my few very picky customers.

3 Likes

Could you please share your environmental conditions, electrical power and your recipes? I am roasting Ethiopian Yirgarcheffe. I would like to try out the soaking idea. Thank you so much!

@VanHoang - Here’s the thread where “heat soak” was first talked about. @quartzglen was the one that introduced it here by that name in Sep 2019. The process was being used by some roasters here well before then but wasn’t identified by name. Read all the way thru the thread as a few things got adjusted by Glen as he detailed the process.

A significant part of Glen’s heat-soak process is managing drum speed. One of the things that became apparent from these drum speed changes was the direct impact drum speed has on RoR, i.e. lowering drum speed tends to increase RoR; increasing drum speed tends to decrease RoR. That’s helpful in managing roast temp since power & fan changes take longer to present themselves. Using drum speed changes without power changes tends to use up heat stored in the drum, so it isn’t an endless resource for temperature management.

Bruce

Thank you so much Bruce! Yes, I read the thread and used this soaking method and started out at D3 until yellow and raised it up. I got a really nice roast. Really happy with it.

Van

Since I roast in a shed that is located away from my residence local environmental conditions can affect the roasting process. I live on the coast of Oregon with humidity most often from 90% to 100% and temperatures in the 9-13C range. I use a dehumidifier to lower the humidity a little and a heater to get a minimum of 15C around the roaster. I only roast in one pound lots and preheat to 240C for a minimum of 35 minutes before charging the machine. Rural electric is not the greatest with power fluctuations always a possibility. I use a Variac to keep a constant 122v going to the Bullet. All of my roasts are on RW at FoggyMtnCoffee, and you can view or download roast profiles from there.

I stick to my “soak” recipe up to 1:30 after beginning of 1c and make manual adjustments until end of roast from there to reach my desired outcome for espresso, drip or pour over or to meet the desired roast level of my few customers. As noted by others drum speed adjustments can really make a direct and immediate change to RoR but I tend to use a more subtile adjustment with P settings and fan speed near the end of the roast.

Gordon

2 Likes

@foggymtn - Other than the coastal Oregon fog (I have < 20% humidity vs. your > 90%), the Variac and using Celsius, this could be a description of my setup & process.

Today I make distinct power adjustments for the soak, but when I looked back at roasts from my HotTop/Artisan combo I can see I delayed application of full power even then. That was a few years before I’d heard of heat soak.

Bruce

1 Like