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Permalink Reply by Jason Haeger on December 28, 2011 at 1:10pm

shorter roast ftw.  I think there's a balancing act between rushing to 1st (resulting in astringency) and stretching the drying phase too long (resulting in papery baking notes).  

Of course, every coffee likes a different approach, imo.

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Permalink Reply by Peter Milne on December 28, 2011 at 6:05pm

I guess it depends what you want, more flavor, body or equal amounts of both.  I roast and sell a bunch of coffee, but I do it all in a cast iron skillet.  No such thing as rushing with this process.

Remember, we are drinking the coffee, not making love to it.  We can really tend to go overboard with it all, ya know.

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Permalink Reply by Dustin DeMers on December 28, 2011 at 10:27pm

This is still a light roast? 50 degrees after first crack, would put me well into second crack.

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Permalink Reply by Corvus Coffee on December 29, 2011 at 8:24am

Yeah, it's still nowhere near second by this point. I have been trying to dance that line Jason was talking about, and I've found if I get enough heat into the roast in the first three minutes I can create some "Thermal Momentum". This allows me to slow the roast down at 4 minutes, and again after first crack. When I say 350 is first crack, that is when I hear 2-3 pops in a row. I track first crack from the very start of it.

My only issue is not that this leaves them too developed, but can tend to mute the flavors too much. Which doesn't make sense to me when comparing this curve to a more standard curve. Have any of you done work with how the low point after drop affects flavor?

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Permalink Reply by Dustin DeMers on December 30, 2011 at 8:51pm

Hmm interesting. (I like to give the warning that i have no idea what im talking about) but I think turning temp is only going to affect the time the coffee spends in the drying phase. Which of course will in turn affect the flavor. I think it has less to do with it turned at 200 vs turning at 240, and more to do with its going to take longer to get out of the drying phase now. Why not test it your self?

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Permalink Reply by Bwynn on January 1, 2012 at 9:18am

I think with the charge temp you are using and full gas for that long,  I would for sure get tipping/scorching and not allow enough time for the yellowing stage. What is the load size you are roasting?  It also sounds as if you are using a environment temp.  I would get a bean probe as it really helps in learning what is happening in relationship to the bean versus the drum.   There are two main types of roasting that i have seen demonstrated.. Fast ramp slow finish (slow down after/ right at first crack) and slow ramp fast finish (at about 310 slow the roast/ turn off heat to develop body until about 10 mins and then back on to the gas and dont worry about times between fc and 2crk too much.)  I am in the fast ramp slow finish.  The main variable with this style is you cannot be too fast in the beginning and too long at the end..  You must try it, Cup & Repeat!   I roast on a Ym-10 and use a bean probe with data logging software! 

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Permalink Reply by Corvus Coffee on January 20, 2012 at 10:46am

Good discussion. We do use both ambient and bean temp, we track both of these for every minute of each roast, which is why I know these factors about the ambient as well as bean temp. The idea behind this roast curve can actually minimize or increase the drying phase if done right. Due to the fact that I'm dropping the gas to about half within the first 3 minutes, the roast has tended to keep the energy gained in that initial higher charge temp. We have never gotten any tipping or scorching and our drying is only taking place for about two minutes depending on when you track it as starting. We have gotten away from the lowering of the gas near the end of the roast and keep it pretty steady right up to when we are dropping. In some of the central American coffees especially, this has really increased the sweetness we are getting out of the coffee.

The temp so far has been affecting a myriad of flavor depending on where and when the temperature is turned down after the initial charge and drop. Without getting into a lot of detail, we have been able to really start nailing down underdeveloped flavors when we cup, and track this back to a lack of heat, or an over abundance of it, at certain points in the curve. This all changes of course with the moisture level within the initial green coffee.

Really enjoying the thoughts around this!

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Permalink Reply by Moffee Coff on March 13, 2012 at 2:19am

Different coffee can benefit from different techniques. You just have to try a few for the coffee you're using and adjust the one which works for you. As for my method it goes a little something like this; boil the kettle. Poor hot water (1cup, not full) into the empty press to warm it up. Tip the water into the cup I'm going to use to warm that up too. Grind the coffee I'm going to use (30g approximately for 3-4 cups, I'm not exact because I adjust coffee and water volumes by 'feel' and experience) into the warm but dry press. I boil the kettle again and then pour. I pour from height, as its more fun and helps wet the grinds quicker ( no blooms, or centre mass, just water in and air out. The air seems to stew the grinds. However, if the coffee foams easily I slow the poor.) Then I quickly get the plunger (filter) in and depress it partially to remove air. I leave it brew for 2min then fully depress.  Then enjoy the coffee. This is what works for me but it's taken practice.

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Permalink Reply by Kevin on March 13, 2012 at 7:06am

In my experience bean density plays a big role in the temperature ramp applied. For example I have found that a less dense Brazilian bean requires a lower drop temperature and less heat applied until the bean aroma changes to hay. SHBs from Central America however do best when dropped at a higher temperature with greater heat applied early in the roast. I roast on a Diedrich - and generally follow the recommended air flow settings throughout the roast - the idea being that early in the roast you allow the moisture in the bean to disperse the heat uniformly into the bean core by keeping air velocity in the drum to a minimum. Air velocity through the drum is increased as the roast develops. I generally aim for a 3 min roast development time which is usually increased if the beans are being roasted for an espresso extraction. 

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