German cacao of Cameroon - new facts on a traditional variety fallen into oblivion

  • Lina Stoll
  • Nicolas Niemenak University of Yaounde I
  • Bernward Bisping
  • Reinhard Lieberei
Keywords: anthocyanin, polyphenol oxidase, polyphenols, cacao, Cameroon

Abstract

“German” cacao cultivated in Cameroon has emerged from a mixture of different gene pools with a large proportion of Trinitario and with a pronounced content of polyphenols. In order to characterize this old genotype, polyphenols and polyphenol oxidase were compared with hybrid selected genotypes. Epicatechin (25 mg/g – 52 mg/g ffdm) and catechin (0.5 – 1.9 mg/g ffdm) content of German cacao seeds were of similar range with hybrid investigated samples. German cacao is characterized by its high content of anthocyanins especially cyadinine-3-arabinosid with a range from 8.84 mg/g to 17.51 mg/g ffdm. Hybrid genotypes displayed 1 mg/g to 6.4 mg/g ffdm of cyanidine-3-arabinosid. PPO activity was 10 to 20-fold higher in German cacao seeds compared to hybrid. Anthocyanin and PPO through the oxidation of phenols to quinone are involved in colour development and pests and diseases resistance. Pigment is one of the most important factors for the colour of cocoa powder. We discussed the high content of anthocyanin and PPO activity in German cacao in relation with the reddish colour of cocoa powder derived from Cameroonian cacao.

Published
2017-09-22