Characterisation of AC1: a naturally decaffeinated coffee

Abstract

We compared the biochemical characteristics of the beans of a naturally decaffeinated Arabica coffee (AC1) discovered in 2004 with those of the widely grown Brazilian Arabica cultivar “Mundo Novo” (MN). Although we observed differences during fruit development, the contents of amino acids, organic acids, chlorogenic acids, soluble sugars and trigonelline were similar in the ripe fruits of AC1 and MN. AC1 beans accumulated theobromine, and caffeine was almost entirely absent. Tests on the supply of [2- 14 C] adenine and enzymatic analysis of theobromine synthase and caffeine synthase in the endosperm of AC1 confirmed that, as in the leaves, caffeine synthesis is blocked during the methylation of theobromine to caffeine. The quality of the final coffee beverage obtained from AC1 was similar to that of MN.Foram comparadas as características bioquímicas das sementes de um cafeeiro Arabica naturalmente descafeinado (AC1), descoberto em 2004, com aquelas da cultivar Mundo Novo (MN), amplamente cultivada no Brasil. Apesar de terem sido observadas diferenças durante o desenvolvimento das sementes, os conteúdos de aminoácidos, ácidos orgânicos, ácidos clorogênicos, açúcares solúveis e trigonelina foram similares nas sementes de frutos maduros de AC1 e MN. Sementes de AC1 acumularam teobromina, e a cafeína estava praticamente ausente. Experimentos com o fornecimento de [2- 14 C] adenina e análises enzimáticas de teobromina sintase e cafeína sintase nas sementes de AC1 confirmaram que, assim como em folhas, a síntese de cafeína é bloqueada na metilação de teobromina a cafeína. A qualidade final da bebida de AC1 foi similar a de MN.