I couldn't find any conclusive agreement on this subject.

I bought some 49th Parallel Epic Espresso in a valve bag a while ago and the Cafe owner told me the coffee hits its peak at about 1 month past roast date because the bag design slows down the oxidation process.

Hmmm...sounded funny to me. I always heard 3 weeks past roast was the longest it would last.

What's the longest time you can keep coffee in a good opaque valve bag (at room temperature) before you need to throw it out?

For me a month sounds a little too long. Each bean is different and then there is roast level etc etc. I use these bags and squeeze out the air and for my tastes most beans are good from 5 days and usually drop off flavor and espresso appears thinner and blacker after 12-16 days. As already stated there are variables but i have yet to enjoy any bean much after this time limit.

This is a very good question that I'd be interested in seeing some good research on. My own limited experience is that that unopened valve bags are kind of on par with freshly frozen (and tightly sealed) coffee. It can keep for quite a while and still be quite impressive when opened weeks later, however, it fades much more quickly. It's like watching one of those rapid CGI-managed aging sequences when a character's immortality is finally undone.

I think that kind of a freshness hysteria is going on here.

Up to 3 months storage in a valvebag is fine with me. A lot of coffees need some time to develop.

I would never drink my self-roasted coffees which I store in porcelain jars earlier than four days after roasting.

The coffees from a very good roaster here in Germany are delivered in valvebags and alwas VERY fresh - TOO fresh. They are best after three to four weeks, everything earlier would be wastage.

I think its better to keep the CO2 in the valvebag instead of squeezing the air out - you lose a lot of aroma.

Ernie wrote:I think that kind of a freshness hysteria is going on here.

Up to 3 months storage in an valvebag is fine with me. A lot of coffees need some time to develop.

I would never drink my self-roasted coffees which I store in porcelain jars earlier than four days after roasting.

The coffees from a very good roaster here in Germany are delivered in valvebags and alwas VERY fresh - TOO fresh. They are best after three to four weeks, everything earlier would be wastage.

I think its better to keep the CO2 in the valvebag instead of squeezing the air out - you lose a lot of aroma.

Thanks for providing another perspective. The Barista I talked to was also convinced the coffee in the good valve bags peaked at around 1 or even 2 months. I'm still not sure but would like to try and find what the general opinion is on the subject from the actual roasters (or an expert taster).

You can drink your coffee however you like and if 6 months stale is fine with you okay.


Valve bags don't preserve freshness. Valve bags allow you to ship fresh without the bag exploding. Oxidization isn't the only thing that stales coffee.

Everyone has a different preference. I love the taste of freshly roasted coffee and generally toss it out after a week or two, when I consider it stale. However, flavors change and develop as time goes on and coffee oxidizes. It depends what flavors you like. Some people will like the flavors after two weeks, a month or more. Some people also enjoy freeze-dried coffee. They are all different flavors and to each his own I say.

Adrian

Adrian got his post out wile i was typing so this may look familiar.

I think when a coffee "peaks" is very subjective, since it is a matter of taste.
I think we can agree that over time no matter how you store the roasted beans the flavor profile will change.

My experience has been that the window of opportunity for espresso is much smaller than for press pot.
To me while the the mouth feel and crema seems to diminish during the first 2.5 to 3 weeks it seems to do so significantly faster in the 4th week, kind of an exponential decay. Also flavors seem to appear and subside during the first 2-2.5 weeks but from that point the start to disappear or flatten to the point that it is not "to me" usable for espresso.

Now my wife and I will still drink this coffee but as press pot. While much of what I said above still holds true for my roasts as press pot, the coffee is still very acceptable for a longer period of time. There are a couple of beans I like better a little "aged" for press pot some of the Colombian's I have roasted come to mind. I did a batch that at 5 days just wasn't for me. A couple weeks later I missed a roast and was running short (at 5:30am something is better than nothing) and that batch was still in the back of the cupboard low and behold it was a very different coffee. However while I have not tested this i can't imagine you would still get the wonderful blueberry flavors from a Harar if you left it in a sealed bag for 6-8 weeks, they seem to fade faster than that.

As far as squeezing the bag what you are smelling has already left the bean and would never make it to your cup. I would be interested to know the science behind whether the higher concentration of CO2 in the bag would slow the decay of delicate flavors.

49th Parallel flushes their bags with nitrogen which might help with a longer shelf life. In my experience, coffees in valved bags can still be great after 4 or more weeks right after opening. However, I've always found that they also fade quickly as soon as they are opened.

A local roaster nearby purposefully ages their coffee 6 weeks in valved bags before sending them to wholesale customers. It was explained to me that this was to make the coffee more stable for their customers (less need for them to adjust their grinder). I wouldn't classify most of their clients as "third wave" type shops.

Cheers
Kaelin

Valve bags flushed with nitrogen, etc. will prevent a lot of oxidization since there is little oxygen in the bag. There are three processes going on with coffee and they compete with each other as time goes on.

First, coffee loses CO2, degassing as time goes on. Generally, this subsides after a few days, but coffee is felt to be better after a rest owing to this.

Second, coffee flavor components decompose by non-oxidative processes. The reductive chemistry of aromatic and tannic molecules generally adds complexity and improves flavor. Look at Pu-Ehr Tea or Red Wine for the precedents here. Thus, coffee generally improves with age.

Thirdly, coffee oxidizes and goes bad acquiring the sour, stale flavors. This process depends on oxygen and the presence of the molecules from Process #2.

THUS, usually coffee gets better with age, but oxidation makes it intolerably stale at some point. Aging roast coffee in nitrogen-flushed bags will allow it to go much further. It is just like how the corked bottle lets wine age properly rather than turning to vinegar.

What you want to do is make sure the bag or container you store the coffee in is flushed with nitrogen. You can usually find this in industrial tanks or buy it as a "wine saver" spray.

Adrian

Freezing in an airtight container yields better results, IMO, than valve-bags at room temp.

There are no good roasters near me, so I buy by mail, usually two pounds at a time. I couldn't finish one pound of coffee before it went stale, let alone two, so freezing is necessary. I move the beans from the bag to an airtight container and put them in the freezer compartment of my refrigerator. There a general consensus that a deep freeze is better than your refrigerator's freezer compartment if you're going to store the beans for more than a couple of months.

Coffee taken from the freezer six weeks later tastes better than coffee taken from the bag after only two weeks, especially with a light roast.

So it seems coffee in a good storage bag with a one-way valve and flushed with nitrogen will last more than 4 weeks? Even 6 weeks perhaps? Maybe more?

I often buy 49th Parallel coffees. They have a webpage devoted to packaging but they make no mention of nitrogen.

http://www.49thparallelroasters.com/packaging.html

Somebody mentioned above that 49th Parallel uses nitrogen? If that is true, why don't they mention that?

While aging might help flavor develop over time you still have to be able to get the right ones in the cup.
While the out gassing proses slows it does not stop.
As most know oil and water do not mix well, the CO2 in the beans is what transports the oils into suspension.
If the CO2 transfer is to vigorous (really big bloom, blond bubbly shot) "beans too Fresh" it is not efficient some flavors get missed and some to strong and they will likely be out of balance. Since things are going so fast the CO2 boiling out can bring out both the undesirable sour and bitter components.
Likewise old beans (no bubbles at all in the press pot, no crema) do not have the energy to transport as much oil (flavor) into suspension leading to flat weak brew of any kind so that and other factors contribute to what I call stale.

As for peak the only way I know to find it is drink the coffee at least every 24 hours after the initial rest. When its really good brew more and enjoy, since tomorrow it wont be the same.

I have noticed coffee can in fact last for decades I found a few cans at an estate sale that were well old enough they could drive in that state. They were next to the machine with foam cups people didn't seem to mind but coffee in the Nebraska badlands is pretty rough. (nearest *$ at the time 75 miles)
So it will last a long time but at some point it is only good for taking the edge off the well water. End humorous but really anecdote.

PS Here is a Fun thread on this very subject over at CG
after you give it a quick read note the dates on the posts

Endo wrote:So it seems coffee in a good storage bag with a one-way valve and flushed with nitrogen will last more than 4 weeks? Even 6 weeks perhaps? Maybe more?

It depends what you mean by "last". On the shelf? After being opened?

If you open two bags at the same time, one of them a simple valve-bag, and the other a nitrogen-flushed bag (or can) containing beans roasted weeks or months earlier, the nitrogen-flushed older roast will deteriorate more rapidly over the ensuing days. That has been my experience at any rate, and you either have to drink coffee past its prime, or waste what is no longer fresh in which case you're not saving any money versus mail-order.

Generally speaking, the lighter the roast, the more rapidly it will deteriorate. You might get up to 10 days after opening on a light roast and up to 20 days on a dark roast. Those numbers are just rough averages.

Endo wrote:So it seems coffee in a good storage bag with a one-way valve and flushed with nitrogen will last more than 4 weeks? Even 6 weeks perhaps? Maybe more?

I often buy 49th Parallel coffees. They have a webpage devoted to packaging but they make no mention of nitrogen.

http://www.49thparallelroasters.com/packaging.html

Somebody mentioned above that 49th Parallel uses nitrogen? If that is true, why don't they mention that?

I think that in some circles Nitrogen flushing is considered a "no,no" (and I'm not 100% sure of the reason why). I have been told by more that one industry person that they practice it.

timo888 wrote:It depends what you mean by "last". On the shelf? After being opened?

I'm referring to "unopened" bags.

buzzmccowan wrote:I think that in some circles Nitrogen flushing is considered a "no,no" (and I'm not 100% sure of the reason why). I have been told by more that one industry person that they practice it.

Interesting. I wonder why anyone would frown on Nitrogen flushing? Anything to preserve it longer would be better I would think, as long as it doesn't influence the taste.

ONE thing I'm very happy about is the fact that MOST good roasters now use a "roasted on" date. That should be a law as far as I'm concerned.

Deoxygenating the container is always a good idea, since it reduces the rate of oxidation of the beans which leads to stale flavors. As a rule, I prefer my coffee as fresh as possible; however, on occasion there are blends that give their best flavors a week or more after roasting. In these cases, I will flush the container with inert gas, like nitrogen, to allow the beans time to mature without oxidizing.

Of course you still have to use the coffee up quickly once you open the container. I suggest storing the coffee in several smaller containers flushed free of oxygen to allow it to keep longer. The home coffee aficionado can use "Wine Preserver" spray or "Whip-It" cannisters as easy to obtain sources of oxygen-poor gas.

Adrian

I was only wondering about the life in the valve bag.

Once open, I always use it up in one week or store it in a "Vacu Vin" container (if I need to stretch it out a bit longer).

An unopened valve bag, or any oxygen-poor container should keep coffee fresh almost indefinitely. I have had beans from 2 months later that were still good. They went stale quickly after I opened the bag.

I have had pipe tobacco from a vacuum-sealed tin that was about 75 years old and it was still fresh, too. So I am pretty confident that unopened coffee valve bags will last a long time.

Adrian

OK, I'm going to offer a different take.
My home roasted Coffee roasted for the purpose of espresso use is roasted in a slightly different manner than the coffee I roast for vac pot/drip use. (I store both in 1 way valve bags. The best have valves made by Bosch, and are more expensive than the ones sold by folks on the coffee co-ops)
I find my espresso roasts generally lose crema, and flatten out taste-wise around 12 days after roast, though they are still wonderfully drinkable in milk or as an Americano. Remember, most folks are used to coffee a YEAR old, and often pre ground.
Now, my coffee roasted for vac pot/drip, etc, stored exactly the same will be delicious even a month after roast.
I attribute this to 2 things:
ONE, the non espresso roast is brought to 1st crack faster, and I shorten the roast times, with a generally lighter roast, most often to city+ (this of course depends on the varietal). Less stress on the bean itself.
TWO, and maybe more significant, brewing under espresso pressure exerts a lot of stress on the coffee, and as the coffee gets pasts it's prime, the loss of freshness is more easily discernible, as is the reduction in the crema.
Just my experience, YMMV.