Coffee degassing

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logicfix

Coffee degassing

Post by logicfix » Tue Sep 11, 2007 7:01 pm

Is anyone degassing their beans in their grinders bean hopper?

Niko

Post by Niko » Tue Sep 11, 2007 7:54 pm

I haven't tried that one but I thought about it recently. It seems like a really good idea for the first 12 hours.

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bbqnut
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Post by bbqnut » Wed Sep 12, 2007 2:02 am

I guess somewhere along the line, I picked up the notion that oxygen deteriorates the beans.

So I always try to de-gass by letting CO2 out, but not letting oxygen in.

Bingo! - Use 1 way valves of some sort (bag or canister). The CO2 always displaces the oxygen (at least until you open the canister). In theory, oxygen would never really be tainting the beans.

That is how I do it anyway, right or wrong.

woodchuck

Post by woodchuck » Wed Sep 12, 2007 8:52 am

Not a bad argument for one way valves at http://coffeetime.wikidot.com/one-way-v ... ee-storage

Cheers

Ian

logicfix

Post by logicfix » Wed Sep 12, 2007 11:40 am

bbqnut wrote:I guess somewhere along the line, I picked up the notion that oxygen deteriorates the beans.

So I always try to de-gass by letting CO2 out, but not letting oxygen in.

Bingo! - Use 1 way valves of some sort (bag or canister). The CO2 always displaces the oxygen (at least until you open the canister). In theory, oxygen would never really be tainting the beans.

That is how I do it anyway, right or wrong.
We all agree that O2 is bad for the bean. Thats not what this is about. I want to minimize O2 exposure to my beans. Currently, as I pour my beans from their degassing jars into the bean hopper, I'm sure that atmospheric levels of 02 (21%) are present within my bean hopper. My thinking is that by letting the beans degas in the grinder, the CO2 would escape by lifting the lid to the bean hopper, or via some other exit, once sufficient pressure had built up. Because the CO2 is heavier than air, the 02 would be pushed out. Thus, the beans would be protected within the grinder by a blanket of their own CO2. However, considering http://coffeetime.wikidot.com/one-way-v ... ee-storage, I wonder if I can install a one way valve in my grid hopper. Does anyone make an industrial one way valve for an application such as this? What about a pure nitrogen or CO2 purge of the grind hopper via a canister/valve setup? OK, maybe thats a bit extreme, but I'm willing to drill a hole in my bean hopper lid and to install a one-way valve. What do you think?

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Post by bbqnut » Wed Sep 12, 2007 2:13 pm

I would think a Bean Hopper is not in any way airtight enough.

That is why I would not consider that option.

But I have been wrong before...

logicfix

Post by logicfix » Wed Sep 12, 2007 2:51 pm

bbqnut wrote:I would think a Bean Hopper is not in any way airtight enough.

That is why I would not consider that option.

But I have been wrong before...
Thats a great point. Are bean hoppers air tight?

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bbqnut
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Post by bbqnut » Wed Sep 12, 2007 6:01 pm

logicfix wrote:
bbqnut wrote:I would think a Bean Hopper is not in any way airtight enough.

That is why I would not consider that option.

But I have been wrong before...
Thats a great point. Are bean hoppers air tight?
Mine definitely are not (Mazzer Mini, Super Jolly, & Macap M4)

logicfix

Post by logicfix » Wed Sep 12, 2007 11:33 pm

bbqnut wrote:
logicfix wrote:
bbqnut wrote:I would think a Bean Hopper is not in any way airtight enough.

That is why I would not consider that option.

But I have been wrong before...
Thats a great point. Are bean hoppers air tight?
Mine definitely are not (Mazzer Mini, Super Jolly, & Macap M4)
So let me get this straight. Keeping beans in the grinder exposes them to a non-airtight environment? Granted its not going to be perfectly sealed, I would think that it would be atleast somewhat air resistant. Otherwise our beans would oxidize quickly and taste nasty. This is begining to sound like a patentable idea: "The airtight, stepless, burr grinder with a semipermeable membrane for degassing coffee beans." Who'll front the money for patenting and development? I'm willing to go 50/50!

Niko

Post by Niko » Thu Sep 13, 2007 12:10 am

All right, I'm jumping back in this conversion after some alone time with my grinders...
They're not airtight, I knew that all along but the Mazzer lids certainly are tighter than the MACAP. The best thing you can do is test this idea of degassing in the hopper by simply doing a taste test of the same amount of beans in the same amount of time. Try roasting about 1lb of your stuff and split half into the grinder hopper and the other half in a one way valved bag, after the first 12 hours move the beans out of the hopper and back into a valved bag for remaining 12 hours and then after both have rested for a total of 24 hours, grind 'em up and taste them over the next couple of days and make your notes.
:D We'll be waiting for your full report :D
I have a similar experiment going with another type of canister....

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Post by Weska » Thu Sep 13, 2007 1:27 am

It would be pretty hard to make a grinder hopper airtight because the bottom is never sealed in use, and the closure at the bottom is designed to be only "beantight." If you aren't using the closure that lets you remove a loaded hopper, then the bottom is open to the burrs. That CO2 is going to drain out the bottom pretty easily in either case.

In general, the most convenient solution for us home roasters to minimize the effects of oxidation is to use what we roast promptly.

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Post by bbqnut » Thu Sep 13, 2007 7:00 pm

I think you need to think longer term.

Many of us roast 1-2 lbs on a Saturday or Sunday, and for convenience sake, have that last us for the week (or in extreme cases 2 weeks)

Having all your beans in a grinder hopper, I am sure at day 4+ would start to taste a lot different than the same beans out of a canister or bag. I am sure because I have done it. And in the case of espresso, the crema is greatly reduced.

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