Development of a flavour wheel for Coffea canephora using rate-all-that-apply

Improving Coffea canephora cup quality became a target for several coffee improvement programs, opening the possibility of sensory profile diversification and opportunities for the recognition of C. canephora by the specialty coffee market. Nonetheless, there is a lack of a defined descriptive tool for evaluating the sensory quality of C. canephora. The aim of this study was to identify the aroma/flavour descriptors of C. canephora samples from 13 different countries of origin and submitted to various postharvest processes (dry and wet processing), with different quality levels (specialty and non-specialty), and organize them in a aroma/flavour wheel for use as a descriptive tool in quality assessment. Altogether, 49 professional coffee graders in both exporting (Brazil) and importing (Switzerland) countries evaluated and described 67 samples in 3 cupping sessions. They used a Rate-All-That-Apply (RATA) list as well as the CQI standard cupping protocol for quality assessment of overall attributes (e.g., aroma, flavour, body, aftertaste) and the final quality score (0-100). A total of 103 descriptors were represented in the three-tiered wheel. 'Roasted' was the Tier 1 category with the highest average mean score, followed by 'sweet', 'fruity', 'cocoa', all the way to 'salty' (the Tier 1 category with the lowest average mean score). The differences between exporting and importing graders regarding (1) the use of descriptive terms, (2) the rated intensity/frequency of certain aroma/flavour categories, and (3) the final score given to both low-grade (i.e., commercial) and specialty coffee samples are discussed. The aroma/flavour wheel can be used as a tool to identify, understand, and map the sensory characteristics of C. canephora that are most important or valued in different markets. Standardizing the description of C. canephora aroma/flavours in a replicable way is important not only for the coffee industry but also for scientists working on quality improvement.