Quality and bioactive compounds of blends of Arabica and Robusta spray-dried coffee

The objective of this study was to develop both a possible process and a spray-dried coffee product with a balanced content of bioactive compounds. Spray-dried coffees were prepared by mixing different ratios of medium-roasted Coffea canephora (R) with green Coffea arabica (A) beans. Overall, quality characteristics of spray-dried coffees were not different. The dominant signals of 1D 1H NMR were identified as trigonelline, caffeine and chlorogenic and organic acids. Principal component analysis explained 81.8% of the total variance. Roasted Robusta spray-dried coffee was clearly distinguished from blended coffees. Forty-two volatile compounds were identified. An increase in green Arabica mixed with roasted Robusta in the blends resulted in an increase in 5-caffeoylquinic acid but a decrease in caffeine contents. Spray-dried coffee prepared from a A35:R65 showed greater total phenolic content and antioxidant activity due to a balance in bioactive compounds. In addition, its coffee brew obtained the highest overall liking score.