Bioactive compounds content in roasted coffee from traditional and modern Coffea arabica cultivars grown under the same edapho-climatic conditions

Abstract

Genetic improvement of coffee is aimed at transferring disease resistance genes from Coffea canephora to Coffea arabica cultivars, but the composition of arabica coffee could be affected by the introgression of genetic material from canephora. The objective of the this work was to compare traditional Brazilian arabica coffee cultivars (Bourbon, Catuaí, and Icatu) with modern arabica cultivars (IAPAR 59, IPR 98, IPR 99, and IPR 103) produced in the same edapho-climatic conditions. The cultivation, harvesting, post-harvesting and roasting processes were standardized to evaluate the influence of genetic diversity on the composition of bioactive compounds (5-caffeoylquinic acid, trigonelline, nicotinic acid, caffeine, cafestol, kahweol, and melanoidins) and antioxidant activity (AA) of the roasted coffees. Compositional variability among the coffee cultivars studied was observed, mainly with regard to contents of 5-caffeoylquinic acid (5-CQA) (from 936 to 1695mg 100g−1), cafestol (from 414 to 742mg 100g−1), and kahweol (from 439 to 1068mg 100g−1). In general, arabica cultivars with the introgression of C. canephora genes showed high antioxidant activity and differed from coffees of traditional arabica genotypes mainly in terms of their diterpenes profiles. A high correlation was observed among the AA (assessed by different methods) and some of the bioactive compounds (melanoidins, caffeine, and 5-CQA). Variability in the levels of the bioactive compounds was higher than that the observed for AA (from 4.2 to 4.7g gallic acid 100g−1 by Folin–Ciocalteau reducing capacity, from 3.75 to 5. 42g Trolox 100g−1 coffee by ABTS radical scavenging activity, and from 80.1 to 83.0 percentage of inhibition of autoxidation of linoleic acid).