In 1963, a chemical engineer named Michael Sivetz introduced the world to the most advanced study ever undertaken on the coffee bean from growing and processing to roasting, brewing and tasting. His findings, published in a book called Coffee Processing Technology, set standards for the global coffee industry. It reveals that coffee quality is a function of: 1) green bean quality, 2) freshness of the roasted beans, and 3) proper brewing method(s).

In 1998, the Specialty Coffee Association of America (SCAA), under President Ted Lingle, republished this book. In 1999, the SCAA adopted the following definition for fresh roasted coffee: (1) ground immediately before brewing; and (2) brewed within three to seven days after it has been roasted, no matter how it has been packaged. Don Holly, Director of the Specialty Coffee Association of America, concluded by saying: "This is not what large wholesale roasters want to hear, because their distribution systems cannot usually deliver coffee to the final consumer in less than a week."

After roasting, coffee produces seven times its volume in inert gases, mainly carbon dioxide. As this gas is produced, it binds with and carries coffee oils (and coffee's fresh taste) into the air as aroma (aromatics). This CO2 envelope naturally protects the coffee from oxygen; its taste assassin, however, 90% of this gas is released within 3 days after roasting. After the gas is gone, oxygen readily penetrates and oxidizies the remaining oils on contact. It is at this moment that coffee develops its characteristic bitter taste. It takes five days for all the gas to escape naturally from whole roasted coffee beans. Grinding accelerates gas discharge to 3 hours - due to greater surface area. Brewing accelerates discharge to 15 minutes - heat accelerates the reaction.

The taste of fresh roasted coffee cannot be preserved! The notion that packaging preserves freshness is false! Sufficient gas is produced by fresh roasted beans to explode conventional packaging, hence the popular use of degassing, metal canisters, vacuum bricks, and bags with one way valves. A bitter taste is the first sign that coffee has gone stale! The market is primarily supplied by companies using a centralized roasting infrastructure with distribution times that range from one week (at best) to two months (on average).

Coffee Technology
Michael Sivetz's authorative book on the subject of producing superior tasting coffee.

Fresh Coffee
By definition, most coffee drinkers have never tasted fresh coffee. There are only two ways to enjoy the great taste of fresh roasted coffee: (1) roast quality green coffee beans at home, or (2) find a local roaster selling certified fresh roasted coffee.