Freshness
Enjoying coffee made from freshly roasted beans is one of the major driving factors in home roasting. The rule of thumb for coffee freshness is that green (unroasted) coffee beans will keep for two years, roasted beans for two weeks, and ground coffee for two hours. Home roasting has the advantage of being able to roast smaller volumes of coffee to match consumption so that the roasted coffee is used before it goes stale. Depending on the origin and method of storage, coffee flavour peaks from 24 hours to 7 days after roasting.
Subsequently, flavour declines at a rate which depends on origin and storage method. The flavour of ground coffee deteriorates even faster. Many factors cause the decline of flavour after roasting, including the oxidation of oils and other compounds exposed to atmospheric oxygen after roasting damages bean cell wall integrity, and the evaporation of flavour-active volatile compounds. Roasting coffee beans produces a significant amount of carbon dioxide (CO2) gas; this CO2 preserves freshness to the extent that it excludes atmospheric oxygen. Other means of extending freshness include refrigeration, freezing, vacuum packaging, and displacing oxygen in ambient air with an inert gas.
Read more about this topic: Home Roasting Coffee
Famous quotes containing the word freshness:
“Our books of science, as they improve in accuracy, are in danger of losing the freshness and vigor and readiness to appreciate the real laws of Nature, which is a marked merit in the ofttimes false theories of the ancients.”
—Henry David Thoreau (1817–1862)
“But the impressions which the morning makes vanish with its dews, and not even the most “persevering mortal” can preserve the memory of its freshness to midday.”
—Henry David Thoreau (1817–1862)