Características funcionales y de calidad en granos de cacao (Theobroma cacao L.) producido en el Norte de Santander, Colombia

Résumé

Cocoa is a widely consumed food with beneficial effects for human health and in Colombia, as a strategy for the substitution of illegal crops (coca cultivation), both the Ministry of Agriculture and the cocoa union promote the planting of cocoa, and consider it a product that generates an environmental, economic and social alternative in postconflict areas such as Catatumbo (Norte de Santander). The fermentation, drying and roasting of cocoa, as operations in the chocolate making process, have an important influence on its sensory and nutritional characteristics; therefore, they could also influence cocoa bioactivity (Hurst et al., 2011; Tonfack-Djikeng et al., 2018). According to the above, an objective of this work was to determine the effect of these stages and especially the cocoa roasting conditions on its antioxidant capacity and the changes in the intestinal microbiota after digestion-fermentation in vitro. HMF and furfural, chemical markers of non-enzymatic browning, were analyzed in unroasted and roasted cocoa powder at different temperatures. The antioxidant capacity decreased with roasting, probably due to the loss of phenolic compounds during heating. On the other hand, HMF and furfural increased during roasting due to increased temperatures. Additionally, roasted and unroasted cocoa powder had different effects on gut microbial communities. Roasted cocoa favored butyrate production while unroasted cocoa significantly favored acetate and propionate production. Furthermore, roasted and unroasted cocoa produced significantly different gut microbial communities in terms of composition. Although many bacteria were affected, Veillonella and Faecalibacterium were some of the most discriminating; while the former is a propionate producer, the latter is a butyrate producer which has also been linked to positive effects on inflammatory gut health and the immune system. Therefore, roasted and unroasted cocoa (regardless of the roasting temperature) stimulates the growth of beneficial bacteria with a prebiotic effect and the production of different SCFAs. For the successful incursion of cocoa in the European market, the quality of the product and the adaptation to regulations such as the EU Regulation No 488 of 2014, regarding the maximum levels of cadmium for specific cocoa and chocolate products, are required. According to this, the type of soils and the content of heavy metals were determined both in soils and in cocoa leaves and beans in two producing areas of the municipalities of Zulia and Tibú by atomic absorption. Physical (texture) and chemical (pH, organic matter, CEC, mineral elements) analyzes were also performed on the sampled soils. The results showed that the soils have acidic conditions for cocoa cultivation. On average, in the two annual harvests, 46% of the grain samples, 100% of the leaves and 50% of the husks analyzed exceeded the maximum value of cadmium established in the European resolution. High values of Al, Ca, K, Mn and Zn in the leaves were similar both in the Zulia and Tibú areas. The pH, % of clay, Al, Mg, Mn and Zn were the variables that had the highest correlation with the concentration of heavy metals. An alternative was proposed with the use of bioactive carbon from cocoa by-products for the remediation of contaminated soils and it was found that the biochar (Cacaochar) obtained from an organic residue of cocoa production (cocoa pod husk) presented good cadmium remediation capacity. The use of SCGchar, bioactive rich in C, showed a significant increase in the concentration of CO in soils.