Protect your coffee… store it correctly

by | Dec 13, 2013 | Coffee science

How should you, the retail consumer, store coffee?

Let us give you our take on this controversial issue. But first, what are we protecting coffee against?

The attacking forces that cause coffee to stale are…
Airborne contaminants like
Moisture Odours like onion, bacon, etc.

Airborne reactants like
Micro-organisms like those that produce sour-dough starter

Heat and light because they speed up the staling effects of the above contaminants and reactants.

Before we break the code on preserving coffee…why is there so much controversy about this issue?

Well, its largely caused by the disregard for the Scientific Method by coffee aficionados during personal experimentation.

For instance, most coffee Gurus store their coffee in a rigid container.  Moreover, most have experimented with storage of their coffee in the fridge or freezer and found that it doesn’t work.

They have found that the taste of the coffee deteriorates when stored this way.  It simply doesn’t work; case closed! Opinion formed!

However, the staling is not caused by the cooler or cold storage environment… It is because, like Elvis, the Scientific Method has, previously, left the building.  The deterioration of the coffee is actually accelerated.

The rigid container prevents the user from eliminating or squeezing out the air in the storage space in and around the coffee before placing it into the cold space. Hence, the air is the metaphorical Trojan Horse that sneaks in the attacking forces 1 and 2 above.

Each time the experimenter takes the rigid container out of the cold space, opens it and spoons out the needed coffee, the cool condensed dry air is replaced with warm moist air.  The moisture, smells, micro-organisms, etc. contained in this air will condense into the coffee and cause further deterioration.

The staling factor is not the cold.  It is the inappropriate container (and, of course, the lack of Scientific Method) which prevents the air and its free-loading coffee enemies form being eliminated.barrier bag with zip and valve

Enter the Scientific Method, accompanied by the barrier bag with one way valve and resealable zip lock.

Incidentally, this is the kind of package in which all our coffee is sold.

Before placing the coffee in the cold as possible storage space, we squeeze out the attacking forces 1 and 2 above and zip the bag closed. Now the fridge or freezer does what its supposed to do, keep out the heat and light.

Importantly, the cold temperature dramatically slows the oxidative process and the metabolism of any free-loading micro-organisms. i.e. This method dramatically slows the staling process keeping the coffee fresh!

One more thought, in order for the coffee to taste fresh until the last  drop,  using the above recommended storage solution,  you must first start with Freshly roasted coffee.

Questions & answers:

Do I have to thaw the coffee before grinding?

No, in fact, the friction caused by grinding coffee generates heat.  Starting with frozen coffee will provide self cooling during the grinding process.  NOTE: For best results, your grinder setting will have to be a tiny bit courser when grinding frozen coffee.

Doesn’t freezing coffee cause permanent changes which affect the taste?

We have seen no scientific information that indicates any changes are not fully reversed by thawing the coffee.

People have told me that freezing causes the oils in coffee to congeal.  Is this bad?

Freezing is used extensively to protect many foods with high oil content like nuts, butter, etc.  Again, we have seen no scientific information that indicates any changes are not fully reversed by thawing the coffee.

I understand that the taste of brewed coffee will benefit from some aging after roasting.  Won’t freezing create problems here?

Freezing will almost stop the aging process.  Used properly, freezing allows the consumer to choose the optimal age for brewing and place the coffee in suspended animation by freezing.  Freezing coffee is a tool that can be used for continually eliciting good taste from coffee over time.

Won’t the moisture in the fridge or freezer cause problems regardless of the package used?

Air in the freezer is too cold to carry much moisture.  Moreover, most freezers are frost (read moisture) free.  Air in the fridge will carry more moisture than the freezer.  However, this will not effect coffee when stored as recommended above.

When I place the coffee from the freezer in my grinder, moisture condenses on it.  Will this create problems?protect-your-coffee-store-it-correctly in a fridge or freezer

This issue will vary depending on whether you live in Coober Pedy or Cairns.  Bottom line, only place coffee in the grinder that you will use in 24 to forty eight hours and the fresh benefits are yours without a downside.

If cold storage is so effective, why don’t coffee roasting companies protect their coffee this way?
Surprisingly, many coffee professionals are unaware of the benefits of cold storage.  Some boutique coffee roasters use cold storage for some aspects of their coffee distribution.  But many are disinclined to wear the expense involved.

I buy my coffee in vacuum brick packs.  Will fridge or freezing it help me prolong the freshness?

The benefits will be limited because the coffee is already stale.
One of the major reasons for vacuum (brick) packing is to economize on transport costs.  i.e. Create uniform sized and shaped coffee packs that will take up the least space.

Before coffee can be vacuum packed, it first has to be left unpacked for days to allow the CO2 to dissipate from the coffee bean or ground coffee.  This degassing allows the bag to retain is brick shape and not become fluffy.

Unfortunately, it allows the coffee to degrade somewhat.  This combined with the extended time in the distribution chain means that your enjoyment will be limited.