Mathematical modelling of the steam stripping of aroma from roast and ground coffee

Research output: Contribution to journalConference article

Authors

Colleges, School and Institutes

External organisations

  • Jacobs Douwe Egberts R&D

Abstract

Instant coffee manufacture involves the aqueous extraction of soluble coffee components followed by drying to form a soluble powder. A challenge that arises from the process is the loss of volatile aroma compounds during evaporative drying. One method of retaining aroma is to first steam strip the volatiles from the coffee and add them back to a concentrated coffee solution just before the final drying stage. Understanding the impact of process conditions on the aroma content of the stripped solution offers engineers the ability to target desirable compounds and maximise their yield. This paper presents a multiscale model for aroma extraction that describes: (i) release from the matrix, (ii) diffusion through the coffee grain, (iii) transfer into water and steam, and (iv) advection through the stripping column. Results reveal how aroma physiochemistry determines the limiting kinetics at industrial extraction conditions. The interaction with the soluble matrix can also inhibit extraction, but this effect varies for the different aromas studied.

Details

Original languageEnglish
Pages (from-to)157-164
JournalEnergy Procedia
Volume161
Publication statusPublished - 18 Mar 2019
EventInternational Conference on Sustainable Energy and Resource Use in Food Chains - Paphos, Cyprus
Duration: 17 Oct 201819 Oct 2018
Conference number: 2nd

Keywords

  • coffee, aroma, flavour, steam stripping, advection-diffusion model