Study paves way for automatic roast monitoring technique using sounds

A new university study has analysed the acoustics of coffee roasting, and provided a potential platform for the automated roast monitoring of coffee via the sounds of first and second crack. The study, by the University of Texas at Austin’s Preston S. Wilson, was published in the June 2014 edition of the Journal of the Acoustical Society of America. Entitled ‘Coffee roasting acoustics’ the paper outlines work done by Wilson recording and analysing the sounds of coffee roasting. The paper acknowledges that expert coffee roasters have for long used the sounds of first and second crack in their roasting processes. The study helps quantify these sounds, to pave the way for an automated roast monitoring tool that would utilise this data. Wilson found that the near the end of the roasting process, the sounds known as first crack “exhibit a higher acoustic amplitude than the sounds emitted later”. He also found that the rate of cracks appearing in the second crack chorus is higher than the rate in the first crack chorus.