Multivariate methods for characterization and classification of espresso coffees from different botanical varieties and types of roast by foam, taste, and mouthfeel

Three espresso coffee (EC) samples of different botanical varieties and typ es of roast were prepared in standard conditions using an experimental EC p rototype: Arabica coffee, Robusta Natural blend, and Robusta Torrefacto ble nd (a special roast by adding sugar). The ECs were characterized with regar d to the physical parameters, amount of total solids, total solids on filtr ate, lipids, caffeine, trigonelline, and chlorogenic acids by HPLC, and sen sory descriptive analysis related to foam appearance, taste, and mouthfeel. Principal component analysis (PCA) was applied to differentiate the EC sam ples. Arabica and Robusta samples were separated successfully by principal component 1 (55.3% of variance) including physicochemical and sensory param eters related to foam and taste of ECs. Torrefacto and Robusta Natural EC s amples were separated by principal component 2 (20.7% of total variance) in cluding mouthfeel and other attributes of color foam. Some interesting corr elations among sensory and physicochemical variables were found. A very sim ple discriminate function was obtained by discriminate analysis allowing th e classification of each EC sample into its respective group with a success rate of 100%.