2024 AIChE Annual Meeting
Quantifying Coffee Freshness for Sustaining the Specialty Coffee Industry
The modern coffee industry places emphasis on the freshness of beans and grounds, which is not necessarily predictable or easily measurable. The current industrial method is to use customer feedback and the production date to measure product freshness, which lacks objectivity in the actual amount the freshness has decayed. This could result in coffee getting discarded unnecessarily. Because coffee is a natural, resource intensive product, it is important to reduce production waste by understanding freshness degradation. This research aims to quantify freshness in coffee beans by investigating how roast level affects the rate of degradation in roasted coffee beans. The findings of this research will contribute to more sustainable practices in the coffee industry by optimizing the use of coffee beans and reducing the environmental impact associated with improper handling of coffee beans.
Green coffee beans were roasted in house to two different roast levels, measured in terms of percent weight loss and color scale. The roasted beans were stored in ambient, airtight containers to simulate consumer/home coffee storage settings. To measure freshness, chemistry-based measurements, such as gas chromatography/ mass spectroscopy (GC/MS) and thermogravimetric analysis (TGA), were employed. The chemical properties were used to characterize freshness of the beans as a function of storage time for the two roast levels, which in turn was correlated to other physical properties (e.g. density) and brew qualities (e.g. pH).