Resonance-enhanced multi-photon ionization time-of-flight mass spectrometry (REMPIITOFMS) has been applied to the detection of volatiles in the headspace of brewed coffee and in the coffee roasting process-gas. A frequency quadrupled Nd : YAG laser (266 nm) was used for REMPI ionization (REMPI@266nm
Studies on acrylamide levels in roasting, storage and brewing of coffee
✍ Scribed by Ingo Lantz; Ruediger Ternité; Jochen Wilkens; Katrin Hoenicke; Helmut Guenther; Gerrit H. D. van der Stegen
- Publisher
- John Wiley and Sons
- Year
- 2006
- Tongue
- English
- Weight
- 440 KB
- Volume
- 50
- Category
- Article
- ISSN
- 1613-4125
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✦ Synopsis
Abstract
The content of acrylamide in coffee reaches a peak early in the roasting process, reflecting occurrence of both formation and destruction of acrylamide during roasting. Levels of acrylamide in the fully roasted product are a small fraction of the peak reached earlier. Glucose and moisture in green coffee do not show a significant correlation with acrylamide in roasted coffee. Pre‐roasting levels of asparagine show a correlation only in Arabica coffee. The main factors affecting the level of acrylamide in roasted coffee appear to be the Arabica/Robusta ratio, with Robusta giving higher levels; time and degree of roast, with both shorter and lighter roasting at the edges of the normal roasting range giving higher levels; storage condition and time, with clear reduction at ambient storage. This storage reduction of acrylamide followed second order reaction kinetics with an activation energy of 73 KJ/mole. The acrylamide in roasted coffee is largely extracted into the brew and stable within usual time of consumption. As these four main factors also substantially affect the sensorial characteristics of the brew, and as modifications of the process have to comply with the consumer‐accepted boundaries of taste profiles, only small effects on the acrylamide level are expected to be achievable.
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