The coffee conservation influences in a definitive way upon the final quality in the cup. This conservation depends that the coffee has to be in contact with oxygen or not, since the essential oils react quickly to oxygen producing a spoil. This can be noticed by simple smell at the bag or at the cup.
The spoiling is faster with grinded coffee that in grain, due to a greater surface contact with oxygen. From the studies done its determined that a grain coffee in contact with air, seven weeks later has a significance quality loss. On the grinded coffee this loss is produced at 8 to 10 days.
To avoid the quality loss, the grain coffee must be packed at empty atmosphere, with a one-way tube that allow to extract the gases that the grains emit. With this the coffee is not in contact with the oxygen and can have a longer lifetime up to a year without quality loss. In the case of grinded coffee it's used the vacuum technique, having only a hard package with a minimum oxygen. Also it can be used the soft hermetic package with dead gas and a tube. On the last case the grinded coffee can be packed immediately after it's grinded. On both cases the product lifetime it's greater than twelve months. Also it's important to remember that once a package is opened, the spoiling will be slower if it's kept with the package close at low temperatures.