Lecture Description
Green coffee defects are an important aspect of coffee quality that is regularly assessed in quality control labs all over the world. The number of defects in green coffee is also strictly regulated, e.g. for Arabica specialty coffee in "The washed Arabica green coffee defect guide”. The lecture summarizes our findings from a CSF-financed study, where we reassessed the relevance and sensory impact of physical green coffee defects on Arabica coffee from Huila, Colombia. The project was structured into three complementary stages:
Sensory Evaluation: The sensory relevance of each defect was assessed through determining attention detection thresholds using 3-alternative forced choice (triangle) tests.
Chemical Characterization: The volatile composition of each defect was assessed in roasted coffee to identify flavor-relevant compounds that are likely responsible for perceived defects using a SIDA-SPME-GC-MS methodology.
Origin and Formation of Defects: Green coffee analyses were conducted with LC-MS to investigate how each defect affects the chemical composition, in order to understand, if defect associated flavour compounds are already present in green coffee or if they are generated during roasting.
Date: Thursday, June 25, 2026
Time: 11:00 - 11:45
Location: Room 1122
Category: Science
Access: This lecture is free to attend with a World of Coffee entry badge. Register to attend World of Coffee here.
Please note that lecture sessions are open on a first-come, first-served basis. Early arrival is highly recommended to secure your seat.
Speaker
Sebastian Opitz
Researcher, ZHAW
Sebastian research interest is focused on green coffee and how green coffee variability influences coffee quality. He works at the Coffee Excellence Center of the Zurich University of Applied Sciences.