Method for keeping roast coffee bean freshness
Abstract
Roast coffee bean freshness is maintained by storing just roasted beans in a sealed container having
much less than 1.00/0 oxygen therein. Storage of roasted coffee at very low temperatures (less than -40 degrees F. (-40 degrees C.)) also preserves the freshness of the coffee. The combination of low
oxygen and low temperature storage provides the freshly roasted coffee taste and a long shelf life for
that preserved taste. Inventors: Sivetz; Michael (3635 NW. Elmwood Dr., Corvallis, OR 97330) Appl. No.: 535055
Filed= March 24, 2000

BACKGROUND OF THE INVENTION ';
This invention relates to coffee, and more specifically to methods and apparatus for retaining the freshness of just roasted coffee beans. The aroma of freshly roasted and ground coffee beans appeals to almost everyone, even children and non-coffee drinkers. However, the marketed coffees pale in aroma and taste compared to the freshly prepared beverages. U.S. Pat. No. 5,368,875 to Hibi et al illustrates the reasons for this difference, as do the Sivetz books: Coffee Processing Technology 1963 and Coffee Technology 1979 and Coffee Quality 1998. Some causes for poor quality are due to the selection of the inferior bean qualities, inefficient methods of roasting, and especially slow cooling of the beans after roasting, up to 24 hour storage of beans before grinding, and additional storage time of the ground beans. The latter two steps are done deliberately to degas the carbon dioxide from the roasted coffee, so that thinner walled evacuated metal cans of roast and ground coffee can be packaged. The degassing steps also cause a major loss in aromatics as well as oxidation, called staling. The fact is that most roast and ground canned coffees are stale at the time of packaging, months before the package of coffee reaches the consumer. Further, the can evacuating machinery, owned and maintained by the steel can fabricators, was developed and applied over 60 years ago, before WWI, and virtually nothing has changed in their performance since. Although, the evacuated cans are alleged to have 90% of their air removed, leaving 2 volume % oxygen, it is well known that residual oxygen in the cans can be as high as 3 or 4%, and much much higher in valve bagged and pouched packages. These conditions clearly and quickly (within 12 hours) result in oxidation of the packaged beans or ground coffee. The major roasters who roast and grind coffees have caused even further quality down grading by adding several percent water, which accelerates the rate and degree of staling. They have also caused complete degassing and produced "brick packs", which is stale aromaless oxidized coffee. Additional down grading has occurred, by using increasing percentages of lower cost, lower taste quality Robusta beans, higher levels of low altitude grown beans with many defects, and fmally creating a system of distribution that causes the canned roast and ground coffee to be in storage or transport for between 3 to 12 months, resulting in continued deterioration of the coffee before it ever reaches the consumer. The latest methods of distribution of roasted beans in valve bags, although less degrading than the roast and ground (R&G) in cans methods, still delivers stale oxidized beans in bulk valve bags, subsequently stored in bean display bins in super markets, thereby undergoing further oxidation. It can be said without contradiction, that roasted beans from such bins are very stale. There are widespread claims by roasters, extolling the unique tastes of coffee beans originating from various geographical areas, e.g., Jamaica, Celebes, Ethiopia, etc. However, the uniqueness of origin is totally lost after the roasted beans oxidize and stale. And such taste distinguishing claims, at the consumer level, not significant.

Some of the factors contributing to the public acceptance as well as provider acceptance of such poor quality stale coffees is the claims by the roasters, that they are delivering "freshly" roasted roast and ground coffees, because vacuum packaging preserves that freshness. This is not true. The truth is that what is sealed in the can and often in the bag, is not freshly roasted at the time of sealing the package. Further, the term "vacuum" is loosely used, without defining degree ofvacuum, and its significance to freshness is not even well understood by the roaster/packager. In addition, the roaster/packager assumes a faulty attitude not based on any facts that such vacuum packaging "protects" the coffee therein for months or even years. These assertions, can easily be dispelled by the use of the CO .sub.2 and oxygen analyzers readily available today and easily operated. These instruments reveal what is really happening to the roast coffee in the various packages. The highlights of these analytical revelations is that they can reveal how aged was the coffee when it was packaged based on CO.sub.2 content. These instruments show that the roasted coffee, whole bean or roast and ground, rapidly reacts with the oxygen in the air, e.g., practically all packaged beans or roast and ground coffee has zero % oxygen present in the container within 12 hours of packaging, because any oxygen that had remained in the bag or can has reacted with the coffee. Preliminary test results show that roast bean coffee in a valve bag sealed with air wi11 have its oxy~en reduced from 20.8% to 10% or less in a few days after packaging. This is accompanied by a loss in aroma; and increased bitterness and stale
notes. Freshly roasted coffee is not bitter, and gives a smooth tasting beverage, whereas roast coffee only days from roasting, shows at room temperature a lack of smoothness, lack of aroma and bitterness. Packaged roast coffees, whether in cans or bags, even at up to 10% oxygen will show zero percent oxygen after just several days of storage. The oxygen is reacting off with the linoleic acid of roasted coffee primarily, but is also oxidizing both aromatic and non-aromatic coffee constituents. Most, if not all, of the coffee processors, do not understand what has been stated here. So many of them buy expensive packaging machinery, e.g., for valve bag use, and believe that a shrunken bag over beans created by vacuum is protecting the coffee, when in fact the vacuum is partial and is leaving high percentages of oxygen in the sealed packages, which will react with the roasted coffee in less than 12 hours. The undefined use of the term "vacuum" is clearly fooling the packaging manufacturer, the roaster/packer and the consumer. In fact some consumers are so naive, that they believe the whole roast beans are fresh, and that vacuum packed coffees are "fresh".
Although small local roasting establishments, called specialty coffee shops, can deliver roasted beans to consumers only a day or few days out of the roasting machine, even 1,000 such places allover the USA, for example, can only supply approximately 5% of the total market demand. And so, it becomes very important to find better means of preservation of the roasted beans until they reach the consumer. It is important to also appreciate the fact that with roast bean storage, even in the first 3 days after roasting, when about 90% of the CO.sub.2 is evolving, that oxygen is not being excluded, and so oxidation is occurring. This phenomena is called gas "diffusion", and it occurs rapidly, within minutes. Therefore, to keep silos and bins, oxygen free is not an easy task nor is it being effectively done in the roasting plants, that choose to degas CO.sub.2 before packaging. Further, the convenience aspect of packaging ground roast coffee beans for the consumers who do not own or use grinders, causes excessive and devastating deterioration of the coffee taste quality .The consumer pays a heavy price when he accepts such convenience, as well as 2 and 3 pound packs, which can only be consumed in 2 to 3 weeks, with roast and ground coffee exposed to air with 20.8 volume % oxygen.

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