Investigating the effect of red beetroot powder concentration and processing time on the bioactive compounds composition and antioxidant capacity of beetroot dark chocolate

[Background]: The development of functional foods is receiving increased recognition as a result of the general interest in healthy diets as part of a healthier lifestyle. This project sought to incorporate red beetroot in dark chocolate and investigate the effect of beetroot powder concentration and processing time on the chocolates' bioactive compound composition, antioxidant capacity, and sugar content.

[Results]: The results showed the presence of bioactive compounds such as betalains and vitamin C in the red beetroot with relatively high antioxidant capacity. The addition of beetroot powder to dark chocolate increased the majority of the bioactive compounds (e.g. catechin, epicatechin, betalains, vitamin C) while at the same time increasing the antioxidant capacity. It also resulted in a decrease in sugar content. Except for vitamin C, processing for more than 12 h had an increasing effect on the majority of the bioactive compounds. Beetroot powder incorporation at a maximum of 30% and processing for 24 h was regarded as optimal.

[Conclusion]: Overall, the present study suggests that red beetroot powder could be added to dark chocolates and processed for more than 12 h to increase the bioactive compounds and overall antioxidant capacity. This research would help to diversify beetroot utilization, reduce post-harvest losses, and improve the overall health-promoting properties of dark chocolate for improved consumer well-being.

This research was supported by the International Foundation for Science (IFS), Stockholm, Sweden, through a grant (Grant no. I3-E-6580-1) to Dr John Edem Kongor. IFS is gratefully acknowledged for its research support. We are also grateful to the Analytical, Instrumental, and Microbiological Techniques Unit (USTA) of the Institute of Food Science, Technology and Nutrition (ICTAN-CSIC), Madrid, Spain, and the CSIC I-COOP program 2021 (Grant no. COOPB20586) for support.

Peer reviewed