Modeling mass and heat transfer in multiphase coffee aroma extraction

Research output: Contribution to journalArticlepeer-review


  • David Beverly
  • Robert Farr
  • John Melrose
  • Sian Henson

Colleges, School and Institutes


Instant coffee manufacture involves the aqueous extraction of soluble coffee components followed by drying to form a soluble powder. Loss of volatile aroma compounds during concentration through evaporation can lower product quality. One method of retaining aroma is to steam-strip volatiles from the coffee and add them back to a concentrated coffee solution before the final drying stage. A better understanding of the impact of process conditions on the aroma content of the stripped solution will improve product design stages. In this context, we present a multiscale model for aroma extraction describing (i) the release from the matrix, (ii) intraparticle diffusion, (iii) transfer into water and steam, and (iv) advection through the column mechanisms. Results revealed (i) the existence of three different types of compound behavior, (ii) how aroma physiochemistry determines the limiting kinetics of extraction, and (iii) that extraction for some aromas can be inhibited by the interaction with other coffee components.


Original languageEnglish
Pages (from-to)11099-11112
Number of pages14
JournalIndustrial & Engineering Chemistry Research
Issue number24
Early online date27 May 2020
Publication statusPublished - 17 Jun 2020