Discriminant analysis for unveiling the origin of roasted coffee samples: A tool for quality control of coffee related products

Abstract

Coffee quality is highly dependent on geographical factors. Based on the chemical characterization of 25 coffee samples from worldwide provenances and same roasting degree, Discriminant Analysis (DA) was employed to develop models that are able to identify the continental or country (Brazil) provenance of blind coffee samples. These models are based on coffee composition, particularly on several key compounds either with or without significant impact on aroma, such as 2,3-butanedione, 2,3-pentanedione, 2-methylbutanal and 2-ethyl-6-methylpyrazine. All models were validated with new and independent data from literature, and also through cross validation and permutation tests. Furthermore, the robustness of the proposed models in case of incomplete characterization data was also tested, being concluded that missing data is supportable by the models. In the whole, this article provides compelling arguments for the development of DA-based tools with the purpose of controlling the quality of coffee in terms of their continental and/or national origins.

Reliable discriminant analysis tool for controlling the roast degree of coffee samples through chemical markers approach

“…Briefly, DA belongs to the class of multivariate statistics and is able to reduce data redundancy [13] through the fitting of first-degree polynomial functions that sort the distribution of each data point within a desired grouping (classes). Examples of research studies on coffee samples that have employed DA technique were published by Powers and Keith [19], Murota [17], Maeztu et al [11], and de Toledo et al [7].…”

Unravelling the relationship between aroma compounds and consumer acceptance: Coffee as an example

“…Coffee is an important agricultural commodity (Samper, Giovannucci, & Vieira, 2017) and plays a vital economic role in many countries (de Toledo, de Melo, & Pezza, 2017). The annual value of coffee is around USD200 billion and 25 million families are associated with the coffee industry (Samper et al, 2017).…”

Efeito do sombreamento na qualidade da bebida de café conilon cultivado em sistemas consorciados

“…A qualidade dos grãos produzidos é baseada em atributos físico-químicos, de forma que os lotes de cafés são classificados comercialmente de acordo com o tamanho de grãos, tipo e a qualidade da bebida (Cheng et al, 2016;Toledo et al, 2017). A classificação quanto ao tamanho dos grãos é realizada pelo peneiramento das amostras, de modo que, quanto maior o tamanho dos grãos maior também o valor de comercialização.…”