JohnB. wrote:The thing I like least about the mason jar full of beans is that once you remove it from the freezer you have a jar full of beans sitting there slowly getting staler each time you open & reseal.

An 8 ounce mason jar only holds 3.5-4 doubles. I usually make 3-4 doubles a day. I suspect there's a lot of people who will be able to go through an 8 ounce jar in 1-2 days.

BTW, nice perspective with the GS3 joke. But really, isn't this whole forum overkill in the eyes of 99% of the population!

JohnB. wrote: My friends, even those that like coffee, think my coffee obsession is way over the top. When I tell them I'm on several coffee forums they just roll their eyes.

Same here. My friends think I'm deranged before my wife tells them what I paid for the GS/3... afterward, and knowing the time and money I spend at cafes and on coffee related products, research, and conversation, they're absolutely sure... Last weekend I was talking to a friend about coffee freshness as we drove from LA up to Monterey, and he was incredulous when I said coffee should preferably be consumed within a week or two at most... and this is a guy who I would put at the 90th percentile of coffee awareness... I'd put the contributors on this forum at the 99.9th percentile...

I will split my pound bag between two jars, tighten up the rings to seal the jars and put them in the freezer. Coffee will keep for several weeks very nicely when sealed and frozen. After a couple of months the coffee does start to degrade more rapidly once the jar has been retrieved from the freezer and put into use.

This topic was discussed to length in Kens Coffee: to freeze or Not to Freeze article. May be a worth while read.

darrensandford wrote:Thinking about the whole vacuum bag thing.

My personal thought is that it is a good idea. I don't imagine that a vacuum bag creates a large negative pressure on the beans, and the amount of "space" for the vacuum to occupy in the bag is very small compared to the amount of CO2 that is outgassed as the coffee is stored, so the amount that outgassing is accelerated will be minimal. There must be a net benefit to removing the oxygen.

Andy S posted this link in another thread. Sivetz PACKAGING ROAST COFFEES.

Does anyone actually package using cans positively pressurized with inert gas?

HB wrote:Metacomment: They don't mention how long it stays fresh after opening. In my limited experience, illy coffee stales very fast -- on the order of 1 to 3 days.

Interesting - have you ever gotten Illy beans recently roasted? (Wondering if the rapid staling effect is limited to beans that are months or years old already, or if even relatively fresh beans would be made to stale quickly by positive pressure prior to opening, and if the latter, how that would work...)

Hmmmm. Next time I'm in Italy, I'll have to try to find some fresh stuff and bring it back to try...

JimWright wrote:Hmmmm. Next time I'm in Italy, I'll have to try to find some fresh stuff and bring it back to try...

Good luck.

Have people been unable to obtain such things? Shoot, I guess maybe so since if memory serves, Mark Prince was apparently unable to obtain much fresh Italian coffee for his espresso-off. Darn.

cafeIKE wrote:Andy S posted this link in another thread. Sivetz PACKAGING ROAST COFFEES.

Man, that was an interesting read! I recently attended one of the cupping classes at Sweet Marias, and Tom mentioned a few times about going into nitrogen flushing as a means of preserving green beans...which called to mind Terroir's comment that they do so with their roasted coffees. Yet they note that this vac bagging & flushing occurs "within a few hours" of roasting. If Sivetz is right, that's too long.

I also wonder about using nitrogen. Wouldn't a packager want a gas that is heavier than O2 if they're using the usual valve-near-the-top bag? Why not just flush with CO2? I'll confess that I may be guilty of splitting hairs here. Terroir goes on to note that they've tried the N-flushed beans stored at room temp over one-week increments and found them still fresh-tasting "for many weeks." That sounds pretty good to me...

Cheers,
Paul

Recently finished reading Chapter 6 of the Illy book, Storage and packaging.

Here is my synopsis:

Factors affecting storage include water, oxygen, and temperature.

About 1-2% of coffee weight is CO2, about 6-10 liters per kg. Driving force of "degassing" is the pressure and concentration gradient. At lower temperature, the CO2 migration slows, therefore the oil migration also slows. CO2 pushes oils out of bean cell structure.

In increasing order of protection: air packaging, vacuum packaging, inert gas packaging, pressurization, and finally, combination of the above with active packaging.

My interpretation of the packaging and degassing process can be explained by the gas equation PV=nRT and slower rate of chemical reactions at lower temperature. By reducing headspace volume and temperature, the shelf life can be prolonged. In the home environment, it would be difficult to achieve pressurized or inert gas packaging. However, we can reduce the rate of oxidation, moisture, and partial oxygen and CO2 pressure and migration by vacuum packaging and freezing.

roblumba is correct in surmising that slight degassing in tight container enhances shelf life. Some inert gas packages are made by placing drops of liquid nitrogen or CO2 (technically not inert gas) into the package.

I started freezing coffee after reading the chapter, and have been taking the packages out 1/2 pound at a time over the past few weeks. So far, I could not detect appreciable difference from non-frozen coffee. However, my palates are probably not as refined as most other people here.

TimEggers wrote:I just pulled a pound of Redline out of the ol' freeze (in original bag with one-way valve) and its absolutely horrid. That's an expensive lesson to learn (and Redline is such a nice blend too).

Huh... really? I do that all the time and had absolutely no problem. I usually buy a 5# bag of greenline, and then 2, 1 pound bags. Freeze one and use the other. Tastes the same to me. Is your fridge funky? Baking soda...

A quick observation about coffee in the freezer. I put coffee in the freezer within hours of roasting. When I don't open the freezer door, degassing doesn't begin until I take the coffee out of the freezer. When I need to constantly open the freezer, the coffee bags begin to bloat, indicating degassing has begun while the bags are still in the freezer.

If you have a large super market look for an item called a reynolds handi vac. These are very cheap and I have been using it with their larger bags. I even looked on e-bay and they are for sale as low as 10 bucks. I get coffee about 2 days out of roast and I leave it in it's original bag with the valve taped over. The handi bag is not very powerful but sucks enough air out of the bag to get a nice seal and I pop it right in the freezer just like that. I have so far had fantastic results and have noticed no deterioration of quality when storing like this. I have so far used beans stored like this 2 months after roast when I needed extra for a party and they were fantastic. I have no doubt they can be stored much longer but I tend to rotate stock out of the freezer about every 3 weeks just to make sure I keep the freshest beans I can available to my quests.

Although I have deviated from this practice I prefer to split the bag when I get it... divvy it up between a few 1 qt zip-loc freezer bags that I squeeze the air out of before sealing... and then put those inside of a 1 gallon size zip-loc freezer bag that is similarly sealed. When I need more coffee I just take out one small bag the night before the morning I plan to toss it in the hopper and then open it in the AM when it's totally thawed.

In the absence of guests - which is only an occasional event in my house - I go through only about a half pound per week and freezing is important for me as a way to preserve freshness.