Frozen Coffee Storage Calculator

Beginner or pro barista, all are invited to share.
User avatar
cafeIKE
Posts: 3083
Joined: Tue Jun 27, 2006 4:53 pm
Real Name: Ian Eales
Equipment: Elektra MXC, Macap MXK & MC4, Vibiemme Domobar DB & HX Super PID, UberHotTop
Location: Woodland Hills, CA

Postby cafeIKE » Fri Jun 18, 2010 8:40 pm

A simple web calculator to approximate the age of frozen coffee based on roast and freeze dates and ambient and freezer temperatures. Calculate a reasonable amount to freeze based on daily consumption.

Image

Frozen Coffee Storage Calculator
You do not have the required permissions to view the files attached to this post.

User avatar
cannonfodder
Team HB
Posts: 8062
Joined: Mon May 23, 2005 8:20 am
Real Name: Dave Stephens
Equipment: Elektra A3, Faema, Gaggia Lever, LaCimbali the list goes on...
Location: Downingtown PA

Postby cannonfodder » Fri Jun 18, 2010 9:57 pm

Interesting. You are using a pretty broad sword with a one fits all calculation but it is interesting. I have had some blends that stored better than others, again a wide generalization but light roasts tend to hold up better than dark roasts in my opinion. However, I have never really done any kind of study on the issue, just a general observation that could be completely wrong. Most of my frozen coffee does not last long enough to do much maximum storage time-line on.

Cool idea and calculator.
Dave Stephens

User avatar
another_jim
Team HB
Posts: 9239
Joined: Thu May 05, 2005 1:16 am
Real Name: Jim Schulman
Location: Chicago

Postby another_jim » Fri Jun 18, 2010 11:27 pm

Nice!

Welcome back Ian, we missed you.

User avatar
cafeIKE
Posts: 3083
Joined: Tue Jun 27, 2006 4:53 pm
Real Name: Ian Eales
Equipment: Elektra MXC, Macap MXK & MC4, Vibiemme Domobar DB & HX Super PID, UberHotTop
Location: Woodland Hills, CA

Postby cafeIKE » Sun Jun 20, 2010 4:40 pm

cannonfodder wrote:light roasts tend to hold up better than dark roasts in my opinion

I agree and added it to the comments.

Thanks

User avatar
shadowfax
Team HB
Posts: 3353
Joined: Wed May 04, 2005 9:18 pm
Real Name: Nicholas Lundgaard
Equipment: Single Group Slayer, La Marzocco Shot Brewer, Compak K10WBC
Location: Houston, TX

Postby shadowfax » Sun Jun 20, 2010 7:08 pm

Nice tool, Ian, and welcome back. Now I need to verify my freezer's actual temperature...
Nicholas Lundgaard

User avatar
cannonfodder
Team HB
Posts: 8062
Joined: Mon May 23, 2005 8:20 am
Real Name: Dave Stephens
Equipment: Elektra A3, Faema, Gaggia Lever, LaCimbali the list goes on...
Location: Downingtown PA

Postby cannonfodder » Sun Jun 20, 2010 8:40 pm

Usually the bottom back is the coldest part. I have an upright deep freezer and it runs around -20F, my kitchen chill chest freezer is set to 0F. There is a noticeable difference between the two. It is evident in the outgas rate of coffee placed in both, or as I like to call it, the bag bloat rate.
Dave Stephens

User avatar
cafeIKE
Posts: 3083
Joined: Tue Jun 27, 2006 4:53 pm
Real Name: Ian Eales
Equipment: Elektra MXC, Macap MXK & MC4, Vibiemme Domobar DB & HX Super PID, UberHotTop
Location: Woodland Hills, CA

Postby cafeIKE » Sun Jun 20, 2010 9:06 pm

I'm sure you know, but Frost Free boxes warm up considerably for a couple hours to remain so. The peak in the chart is exactly 2 hours between minimums. The net effect is to raise the average by a degree or so.

Image

If a long average is not taken, a reading at the top of the defrost cycle can be quite misleading.
You do not have the required permissions to view the files attached to this post.

User avatar
cannonfodder
Team HB
Posts: 8062
Joined: Mon May 23, 2005 8:20 am
Real Name: Dave Stephens
Equipment: Elektra A3, Faema, Gaggia Lever, LaCimbali the list goes on...
Location: Downingtown PA

Postby cannonfodder » Mon Jun 21, 2010 10:00 am

I use to have a frost free kitchen freezer (side by side). I opened the door one day and hear a odd sizzle like water dropping on a hot pan. I could push in the door plunger to turn off the light and see a light red glow. It was the cooling coils in a defrost cycle glowing red. Quite disconcerting the first time you see it. My upright draws a vacuum when the door is closed to seal everything up. Another unexpected sound, shut the door and you get about 5 seconds of a sucking/hissing noise. You can actually see the door gaskets compress. If you are going to data log your freezer, best to put the probe in the freezer, mid point suspended in mid air. Then give it a day and then start your logging for 24 hours, through out the high and low and there is your average temperature.
Dave Stephens

User avatar
cafeIKE
Posts: 3083
Joined: Tue Jun 27, 2006 4:53 pm
Real Name: Ian Eales
Equipment: Elektra MXC, Macap MXK & MC4, Vibiemme Domobar DB & HX Super PID, UberHotTop
Location: Woodland Hills, CA

Postby cafeIKE » Mon Jun 21, 2010 10:11 am

For data logging the average cold temperatures, use a small plastic bottle filled with 50% water and 50% methyl hydrate. The solution doesn't solidify and gives a very good average, smoothing out the peaks and valleys in the graph above.

Place the probe through a hole in the cap mid way in the solution. With a good seal, it's a lifetime tool.

Ken Fox
Posts: 2453
Joined: Fri Oct 28, 2005 11:12 pm
Real Name: Ken Fox
Equipment: Too much
Location: Idaho

Postby Ken Fox » Mon Jun 21, 2010 12:47 pm

Hi Ian,

As previously said, welcome back to HB!

Your idea of having an online calculator that can estimate the rate of coffee staling in a freezer is interesting and has merit. I would caution however that our "molecular" understanding of what is actually going on with frozen roasted coffee, particularly as it applies to what we call "staling" in coffee stored at room temperature, is somewhat limited. We know that freezing "works." We also know that oxidation is slowed down with reduction in temperature. We know that coffee degasses as it ages, and presumably this has some relationship to the "staling" process. We know there are oils in roasted coffee that are in a liquid state at room temperature and that presumably are in a solid state when frozen. What we don't know is how exactly we can quantify this thing we call "staling," because we don't know that oxidation and degassing, which may be quantifiable vis-a-vis changes in storage temperature, are the only things going on that relate to staling.

Unlike some here, I freeze my roasted coffee immediately after roasting. I have not necessarily noticed an obvious correlation between freezer temperature and the extent to which plastic storage bags "pump up" over time. Even if I did, I think it would be a bit presumptive to assume that the extent to which the bag puffs up correlates exactly with the rate of what we call staling. There may be other factors at play that explain limited degassing in the frozen bag of coffee, such as small, unrecognized variations in roast profile, degree of roast, or the green coffee itself that was roasted before freezing.

Having a rough idea of how quickly your frozen coffee will "stale" is of course a good thing. From a practical standpoint, I would encourage people to freeze as quickly after roasting as possible, to use the coldest freezer they have available, and to freeze in portions that can easily be consumed within a 3 or 4 day window. There is obvious benefit in having a stash of coffee in the freezer, as it does allow you to have more different types of coffee available for use at a given time, and to time shift your roasting sessions. At the same time, beyond a certain point, the convenience factor and availability of several coffees simultaneously is no longer benefited once one has a certain amount of coffee in the freezer. So, it is probably better to keep your frozen stash down to the point where you don't have frozen coffee that is older than several months post roast. Following these above guidelines should allow one to end up with the best possible results from the coffee that one freezes.

As I have posted before, I find that most coffees have a fairly brief period after roasting where they show the best, for espresso. As a result, I'm tending to leave less coffee of any particular type out after a roast session, and to freeze more of the roast product of each session, in small containers (most typically ~150 to 180g, in my own case). By using this strategy I find that I can consume most of my coffee at its peak, rather than watching it go downhill as I consume it.

ken
What, me worry?

Alfred E. Neuman, 1955