Extending Freshly Roasted Coffee Lifespan

The main enemies of Freshly Roasted Coffee are Time, Oxygen, and Moisture.

A solution has been presented to the public that is more beneficial to the manufacturers than to the end user.

Background info:

Immediately after roasting the coffee beans begin to emit carbon dioxide in sufficient volume and pressure to burst a hermetically sealed bag.  Some roasters opted to degas the beans for one to three days to alleviate this problem while manufacturers came up with a new product, the valve.
http://nxt-roasters.blogspot.com/2011/12/do-coffee-bag-valves-leak-1.html
http://nxt-roasters.blogspot.com/2012/05/revisited.html

Valve Limitation - as currently used:

It is possible that the valve is a single solution to burst bags when with a little more thought it could have also help to extend the freshness of coffee beans.

The CO2 is roughly 50% denser than the air we breathe, which consists of about 21% Oxygen.  This means when packaged, on the first day, beans emit CO2 that gas drops to the lowest level in the container and pushes the existing air upwards.  Surrounded the Freshly Roasted Coffee Beans with CO2 retards the oxidation process, hence, slows down the staling process.  How well and for how long the freshness is preserved is much more difficult to assess and beyond the limits of a one page blog entry.  For arguments sake I say it gives an extra week.  This process exists for the beans that are continually bathed in CO2 which is not the case when there is a venting valve.  As shown in the photo the CO2 will rise up to the valve then exit rather than flush out the air above the valve.  That means that, as the photo illustrates, that only 2/3 of the beans are in CO2 providing the bag is not tilted.  If the bag was laid on it back so that the valve was at the high point of the bag then there would be a different outcome but bags are not stored, shipped, or displayed laying down.  That scenario would be improved by moving the valve upwards to minimize the amount of air in the bag.

Using a valve does allow the roaster to degas in the heat sealed bag which offers the consumers the security and assurance that the bag contents have not been tampered with.

Alternatives:

The NXT solution to this dilemma is to use a ziplock bag which presents more flexible packaging options.  First, all the oxygenated air is pushed out of the bag when the bag is kept upright.  We recommend that people scoop out the beans for immediate consumption rather than pour them out which would drain much of the CO2.  Leaving CO2 to protect the beans extends the freshness.  Our bags are in a supervised area and they are not opened after closing but for added security, where bags are placed in a public area and a heat seal is required a simple pin prick between the ziplock and the heat seal which will prevent bursting the bag and allow a flushing of the oxygenated air.

NXT advocates degassing in the bag to take advantage of the emitted CO2 to extend the freshness of the coffee beans.

We have a Carbon Dioxide high pressure tank and a regulator to test the effect of giving a shot of CO2 to a bag of beans that are more than a day old when outgassing has mostly ceased.

It might mean some beans will be destroyed with water to determine the volume of the interstitial spaces which will indicate how much CO2 has to be injected to bathe all the beans in a protective gas.

To Do:

Test to determine how CO2 will enhance the life of ground coffee.

Freshly Roasted Coffee & Solubles

It is accepted that Freshly Roasted Coffee Beans are essential to a great coffee experience.

This is a preliminary exploration of two brewing methods; modified Turkish and espresso.  The hypothesis is that it is possible to increase the G forces on the brew for accelerated sedimentation of the coffee fines.  The accumulation of solids in the bottom would support the idea that it is possible to quantify the coffee strength for various brewing methods.  For now, it is assumed that the amount of solubles is directly related to the strength of the coffee.

At the top is a modified Turkish brew without the addition of Cardamon and Cinnamon.  Essentially it is coffee made with a very fine grind which remains in the cup.  Of course if the drinker insists on consuming the proverbial last drop he/she will also have a 10 g breakfast.  For this comparison the water to coffee ground ratio of 10:1 was used.  The brew decanted for approximately 2 minutes before 14 ml were removed and placed into the vial or tube.

 The espresso was made with 15 g of coffee which was pulled in 29 seconds to yield two ounces or 60 ml.  Again, 14 ml was transferred to a tube for further processing or accelerated decantation.

The espresso grind is tamped in the porta-filter which only allows smaller particles to pass through with the water.

The fine grind, brew in a cup on the other hand is initially separated by gravity alone.  Since it is not filtered it is possible that the larger grounds are decanted in the first 2 minutes.  The larger the grind the longer it takes to decant but since this is an extra fine grind it is possible that the 2 minutes was sufficient to decant even the largest particles.  Smaller particles may be held in suspension in the liquid whether by turbulence, Brownian forces, or magic.

Both brews were initially opaque when held in front of a light.

The results above are open to interpretation until further experiments are done.  All three vials show signs of sedimentation but the Turkish Grind had significantly more grinds in the bottom.  It may be possible to conclude that the particles were larger than those in the espresso.  The increased transparency does support the premise that the previous opaqueness was due to the larger particles.

The espresso remained largely unchanged.  It is difficult to establish with precision that .25 ml of fines were decanted.  The opaqueness of the processed espresso does support the idea that extremely fine particles are held in suspension.

The experiment did not support the hoped for conclusion where the amount of solubles could be measured and even categorized.  It appears that a greater G force will be required to compare drip coffee, to say, a brew done in a French Press.  Or to compare the brew of large chains to that of a K cup.

Hopefully, another iteration of this test will allow the measurement of a solubles so that  brewing can be optimized.  Without measurement it is difficult to optimize so many variables.

Now, a cup of coffee is needed to start the process.