No matter how carefully coffee is grown,
processed, blended, roasted, ground and brewed, the ultimate quality
depends on one overall factor: freshness. Considering the ready
availability of ground coffee, there would never be any real reason to
grind coffee beans at all – except, crucially, to obtain the freshest
possible taste. When coffee is roasted, carbon dioxide develops within the
beans; it escapes from the coffee for several hours, and does so with a
force that ruptures seams in tin cans and causes softer packages to
"balloon". Many roasters, therefore, allow the roasted beans or ground
coffee to stand for hours before packing. Of course, while standing, the
coffee goes stale, losing its volatile aromas and absorbing tasteless
Given the practicalities of coffee packaging (which can be vacuum-sealed
tins (cans), brick packs, one-way valve-lock bags, or gas-flushed packs,
all trying to let the gas out and keep the freshness in), no coffee is
ever 100 per cent fresh. It's no good trying to roast, grind and brew
coffee within a few minutes because, until the coffee has degassed, it
will not taste good.
However, the fact is that roasted beans do retain their freshness longer
than ground coffee, as there is less cell surface exposed to the air.
Assuming that the roasting company and the retailer have just roasted the
beans and maintained their freshness, the obvious next question is how
best to store them at home.
Experts differ widely in advice on storing coffee, particularly beans.
Certainly coffee can absorb odors easily, and will taste of those odors
when brewed. Therefore some people advise against keeping coffee in the
fridge. Others advocate using an airtight container, which will keep out
oxygen, but what about the oxygen sealed inside with the beans? The
solution would be to keep the surface of the beans very high in the jar,
but then one could never use the beans further down in the jar.
Even the freezing of beans has its opponents, who say that after freezing,
the coffee will never taste the same. Certainly, freezing darker-roasted
beans, which have an oily surface, is definitely not a good idea, as the
oils congeal and never regain their original consistency and distribution
throughout the coffee.
The ideal solution to the problem of keeping coffee fresh is to purchase
smaller amounts more frequently. In Italy, for example, many people buy
small amounts, perhaps 100-200g/ 31.2-7oz of coffee several times a week
from their local coffee bar; they choose a blend of roasted beans, and the
barista (barman) grinds them. The ground coffee is then placed in a
grease-lined paper bag. Similarly, a person who shops infrequently could
still maximize the freshness of the coffee by buying several smaller packs
of factory-sealed coffee instead of one or two large packs, as unopened
factory-sealed containers will stay fresh for many months.