Engineering Commons^™

Mass Transfer Effects Of Particle Size On Brewing Espresso, Sichen Zhong, Lauren Elizabeth Stork

Rose-Hulman Undergraduate Research Publications

The extraction process for coffee is complicated due to the nature of the coffee. In this paper, we studied the particle size distribution for coffee grinds and further analyzed that with the help of an inverted microscope and a scanning electron microscope. We drew a conclusion that the coffee grinds can be divided into two parts: cell fragments with smaller particles size and intact coffee cells with larger particles. The intact coffee cell was found to be a porous media. Therefore, we tried to brew the espresso with both normal grind size coffee and sieved coffee to study the extraction …