At what temps do you drop your green into your roaster ?

[Blucifer]

Hey gang,

Well im new here and im new to roasting. Im roasting on a Diedrich IR-3. I have read throught the Kenneth Davids books, my Diedrich manual, some older roasting logs and little bits of stuff i can get in magazines and here online. Seems everybody has a slightly different way of doing things and a reason as to why they do things they way they do. So as a newbie im trying to form oppionions of my own by what makes sence to me from what limited resources I have. I have a million and one questions and almost nowhere to go to ask them so im going to start here to see what kind of reaction i can get. So as not to overwhelm the group or myself with all the answers I (hope to) get, im going to try asking one or two questions every other day or so i have ample time to digest things. ALL help on this is VERY appricated !

Ok, first question. Seems like everybody drops their green coffee into the roaster at different temps. I have read everywhere from 300-450. One source says dropping it at too high a temp can cause scorching. What temps do you all drop your coffee into your roasters, and why ?

Again, ALL help on this is VERY appricated !

Thanks
Blu

 

[Fresh Roaster]

If you're doing it to achieve real consistency you have to take into account, water content, weight and type of bean and ambient temperature. The mass of the beans in their unheated state has significant impact.

If you're using time and temperature as your model, there's no possible way to achieve absolute consistency off a standard model. No way humanly possible. But, a good standard I've seen is:

5 pounds: 430
3 pounds: 420
1 pound: 410

 

[green beans]

Roasters

I do not want to take away from other questions asked but can someone explain the main differences between gas and electric roasters?

Is it a preference thing or just that gas yields the best results?


thanks

 

[Davec]

Re: Roasters

I do not want to take away from other questions asked but can someone explain the main differences between gas and electric roasters?

Is it a preference thing or just that gas yields the best results?


thanks

You have 3 main methods of heating coffee:

Conduction (heat transferred by contact with a hot surface)
Convection (heat transferred by hot air)
Radiation (heat transferred by infra red radiating from a hot object)

In the examples below I am going to use % figures, but these are guestimates, just to illustrate the relative proportions that might be involved and not representitive of actual data.

Gas roasters might use Conduction (30%) Convection (60%) Radiation (10%).

Electric roasters (element outside drum) might use Conduction (20%) Convection (20%) Radiation (60%)

Electric roasters (element inside drum) might use Conduction (15%) Convection (10%) Radiation (75%)

Electric roasters (fluid bed/hot air) might use Conduction (2%) Convection (97%) Radiation (1%)

In terms of the difference between the two types (apart from the obvious), for roasters of a given size, the method of heating the beans varies. This can lead to different problems for different types of roasters (e.g. bean schorching, outside roasted faster than inside, uneven roast etc..). If however the roaster is properly controlled (gas or electric drum roasters) and has sufficient power, the results will be similar, with the exception of fluid bed roasters.

As roasters get larger, electric becomes a much more problematic method of heating and gas is the only practical solution. Gas does produce a much hotter flue, so small electric roasters are commonly used at home and as small shop roasters.

 

[green beans]

Thanks for the great reply Davec.


So am I correct in understanding that the reason people boast about their old school gas roasters is more because of the old school factor, not that it actually produces different beans than electric roasters?


If it is the case that the same roasts can be achieved with both gas and electric what makes one more popular, or is one method more popular.


Thanks again for any feedback.

 

[Davec]

So am I correct in understanding that the reason people boast about their old school gas roasters is more because of the old school factor, not that it actually produces different beans than electric roasters?

If it is the case that the same roasts can be achieved with both gas and electric what makes one more popular, or is one method more popular.

Well if I wanted a small shop roaster and flu temperature and fire considerations were a problem, I might be more inclined to go electric (of course our wiring is thnner in the UK for a given amount of power). If it was a large roaster in a commercial operation, then gas every time.

As for the same roast, all roasters are a bit different, even the same make and model of roaster will probably roast a bit differently.

All people who roast will roast a bit different

The ambient conditions, type of coffee etc.. will again make a further difference.

So replicating the same roast is always more tricky for more reasons than just the method used to heat the beans. However I think it might be fairly well agreed on (by people who don't fluid air roast), that high speed fluid bed roasting is prehaps not an ideal method of applying heat energy to the beans

My own belief....it's "simply" :wink: a matter of applying the right amount of heat to the beans, at the right time in the roasting cycle, for the right duration, to get roasts that are pretty good. In general less than 14 minutes and more than 20 mins is not good....then there is profiling e.g. applying loads of heat to the beans too early on and coasting them to a final roast 19 minutes later won't be that good either.

it's...complicated, but after a few hundred roasts you get the idea....you learn even quicker the larger your roaster is :roll:

 

[NW JAVA]

hehe I never read anything, never understudied roast on an ir-3 and have killer response. The thing is that I spent the time, effort and expece to get the best profiles and roast style I could. It's an individuals talent combined with whatever else it takes to get the individual's roast style. No wonder ppl ask me why my coffee is so much different and better than the others around here.

 

[NW JAVA]

That was supposed to be : I never read any roasting book, and I roast on an ir 3.

 

[Davec]

That was supposed to be : I never read any roasting book, and I roast on an ir 3.

:wink:

 

[scottlindner]

hehe I never read anything, never understudied roast on an ir-3 and have killer response. The thing is that I spent the time, effort and expece to get the best profiles and roast style I could. It's an individuals talent combined with whatever else it takes to get the individual's roast style. No wonder ppl ask me why my coffee is so much different and better than the others around here.

So what's the roasting profile secret?

 

[green beans]

Green Coffee Bean Supplier

Can anyone give me the names of some green coffee bean suppliers near the northeast? Looking for a good fair-trade supplier but interested in all good coffee, thanks.