Researchers at the Swiss Federal Institute of Technology in Zurich, together with the company DMP, developed a mass balance that accounts for gravimetrically measured roast loss.
Essentially, their technology improves understanding of the roasting process, and consequently how to retain more volatiles to better the aroma profile of coffee.
If the smell of brewing coffee boosts consumer coffee consumption, this methodology could be a valuable asset to the competitive coffee making market. Coffee consumption is common throughout the world, with retail sales hitting over €54 billion and dominated by number one instant coffee maker Nestle.
"Carbon dioxide evolution and differentiation between evaporation of initial water and chemically formed water showed that chemical reactions leading to relevant amounts of carbon dioxide and water start at approximately 180 °C," report the authors of the study.
The Swiss-developed technology was able to measure carbon dioxide evolution in two different processes (isothermal high-temperature short time, and low-temperature long-time roasting process).
In addition, the mass balance tracked carbon dioxide release during storage. Carbon dioxide and water vapour concentration were evaluated in exhaust air by non-dispersive infrared gas analysis.
After being dogged in recent years by poor prices following a glut in coffee production, prices are just starting to recover for the global coffee bean industry. A surge in Arabica prices recorded during the last quarter of 2004 continued into January 2005.
According to the International Coffee Organisation, most of January's Arabica transactions involved price levels of over US107 cents/lb compared to below US 70 cents/lb a year ago.
Full findings for the study are published in the Journal of Food Science, 70(2):E124-30.